| //===--- SemaChecking.cpp - Extra Semantic Checking -----------------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements extra semantic analysis beyond what is enforced |
| // by the C type system. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "clang/Sema/Initialization.h" |
| #include "clang/Sema/Sema.h" |
| #include "clang/Sema/SemaInternal.h" |
| #include "clang/Sema/Initialization.h" |
| #include "clang/Sema/Lookup.h" |
| #include "clang/Sema/ScopeInfo.h" |
| #include "clang/Analysis/Analyses/FormatString.h" |
| #include "clang/AST/ASTContext.h" |
| #include "clang/AST/CharUnits.h" |
| #include "clang/AST/DeclCXX.h" |
| #include "clang/AST/DeclObjC.h" |
| #include "clang/AST/Expr.h" |
| #include "clang/AST/ExprCXX.h" |
| #include "clang/AST/ExprObjC.h" |
| #include "clang/AST/EvaluatedExprVisitor.h" |
| #include "clang/AST/DeclObjC.h" |
| #include "clang/AST/StmtCXX.h" |
| #include "clang/AST/StmtObjC.h" |
| #include "clang/Lex/Preprocessor.h" |
| #include "llvm/ADT/BitVector.h" |
| #include "llvm/ADT/SmallString.h" |
| #include "llvm/ADT/STLExtras.h" |
| #include "llvm/Support/raw_ostream.h" |
| #include "clang/Basic/TargetBuiltins.h" |
| #include "clang/Basic/TargetInfo.h" |
| #include "clang/Basic/ConvertUTF.h" |
| #include <limits> |
| using namespace clang; |
| using namespace sema; |
| |
| SourceLocation Sema::getLocationOfStringLiteralByte(const StringLiteral *SL, |
| unsigned ByteNo) const { |
| return SL->getLocationOfByte(ByteNo, PP.getSourceManager(), |
| PP.getLangOpts(), PP.getTargetInfo()); |
| } |
| |
| /// Checks that a call expression's argument count is the desired number. |
| /// This is useful when doing custom type-checking. Returns true on error. |
| static bool checkArgCount(Sema &S, CallExpr *call, unsigned desiredArgCount) { |
| unsigned argCount = call->getNumArgs(); |
| if (argCount == desiredArgCount) return false; |
| |
| if (argCount < desiredArgCount) |
| return S.Diag(call->getLocEnd(), diag::err_typecheck_call_too_few_args) |
| << 0 /*function call*/ << desiredArgCount << argCount |
| << call->getSourceRange(); |
| |
| // Highlight all the excess arguments. |
| SourceRange range(call->getArg(desiredArgCount)->getLocStart(), |
| call->getArg(argCount - 1)->getLocEnd()); |
| |
| return S.Diag(range.getBegin(), diag::err_typecheck_call_too_many_args) |
| << 0 /*function call*/ << desiredArgCount << argCount |
| << call->getArg(1)->getSourceRange(); |
| } |
| |
| /// Check that the first argument to __builtin_annotation is an integer |
| /// and the second argument is a non-wide string literal. |
| static bool SemaBuiltinAnnotation(Sema &S, CallExpr *TheCall) { |
| if (checkArgCount(S, TheCall, 2)) |
| return true; |
| |
| // First argument should be an integer. |
| Expr *ValArg = TheCall->getArg(0); |
| QualType Ty = ValArg->getType(); |
| if (!Ty->isIntegerType()) { |
| S.Diag(ValArg->getLocStart(), diag::err_builtin_annotation_first_arg) |
| << ValArg->getSourceRange(); |
| return true; |
| } |
| |
| // Second argument should be a constant string. |
| Expr *StrArg = TheCall->getArg(1)->IgnoreParenCasts(); |
| StringLiteral *Literal = dyn_cast<StringLiteral>(StrArg); |
| if (!Literal || !Literal->isAscii()) { |
| S.Diag(StrArg->getLocStart(), diag::err_builtin_annotation_second_arg) |
| << StrArg->getSourceRange(); |
| return true; |
| } |
| |
| TheCall->setType(Ty); |
| return false; |
| } |
| |
| ExprResult |
| Sema::CheckBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall) { |
| ExprResult TheCallResult(Owned(TheCall)); |
| |
| // Find out if any arguments are required to be integer constant expressions. |
| unsigned ICEArguments = 0; |
| ASTContext::GetBuiltinTypeError Error; |
| Context.GetBuiltinType(BuiltinID, Error, &ICEArguments); |
| if (Error != ASTContext::GE_None) |
| ICEArguments = 0; // Don't diagnose previously diagnosed errors. |
| |
| // If any arguments are required to be ICE's, check and diagnose. |
| for (unsigned ArgNo = 0; ICEArguments != 0; ++ArgNo) { |
| // Skip arguments not required to be ICE's. |
| if ((ICEArguments & (1 << ArgNo)) == 0) continue; |
| |
| llvm::APSInt Result; |
| if (SemaBuiltinConstantArg(TheCall, ArgNo, Result)) |
| return true; |
| ICEArguments &= ~(1 << ArgNo); |
| } |
| |
| switch (BuiltinID) { |
| case Builtin::BI__builtin___CFStringMakeConstantString: |
| assert(TheCall->getNumArgs() == 1 && |
| "Wrong # arguments to builtin CFStringMakeConstantString"); |
| if (CheckObjCString(TheCall->getArg(0))) |
| return ExprError(); |
| break; |
| case Builtin::BI__builtin_stdarg_start: |
| case Builtin::BI__builtin_va_start: |
| if (SemaBuiltinVAStart(TheCall)) |
| return ExprError(); |
| break; |
| case Builtin::BI__builtin_isgreater: |
| case Builtin::BI__builtin_isgreaterequal: |
| case Builtin::BI__builtin_isless: |
| case Builtin::BI__builtin_islessequal: |
| case Builtin::BI__builtin_islessgreater: |
| case Builtin::BI__builtin_isunordered: |
| if (SemaBuiltinUnorderedCompare(TheCall)) |
| return ExprError(); |
| break; |
| case Builtin::BI__builtin_fpclassify: |
| if (SemaBuiltinFPClassification(TheCall, 6)) |
| return ExprError(); |
| break; |
| case Builtin::BI__builtin_isfinite: |
| case Builtin::BI__builtin_isinf: |
| case Builtin::BI__builtin_isinf_sign: |
| case Builtin::BI__builtin_isnan: |
| case Builtin::BI__builtin_isnormal: |
| if (SemaBuiltinFPClassification(TheCall, 1)) |
| return ExprError(); |
| break; |
| case Builtin::BI__builtin_shufflevector: |
| return SemaBuiltinShuffleVector(TheCall); |
| // TheCall will be freed by the smart pointer here, but that's fine, since |
| // SemaBuiltinShuffleVector guts it, but then doesn't release it. |
| case Builtin::BI__builtin_prefetch: |
| if (SemaBuiltinPrefetch(TheCall)) |
| return ExprError(); |
| break; |
| case Builtin::BI__builtin_object_size: |
| if (SemaBuiltinObjectSize(TheCall)) |
| return ExprError(); |
| break; |
| case Builtin::BI__builtin_longjmp: |
| if (SemaBuiltinLongjmp(TheCall)) |
| return ExprError(); |
| break; |
| |
| case Builtin::BI__builtin_classify_type: |
| if (checkArgCount(*this, TheCall, 1)) return true; |
| TheCall->setType(Context.IntTy); |
| break; |
| case Builtin::BI__builtin_constant_p: |
| if (checkArgCount(*this, TheCall, 1)) return true; |
| TheCall->setType(Context.IntTy); |
| break; |
| case Builtin::BI__sync_fetch_and_add: |
| case Builtin::BI__sync_fetch_and_add_1: |
| case Builtin::BI__sync_fetch_and_add_2: |
| case Builtin::BI__sync_fetch_and_add_4: |
| case Builtin::BI__sync_fetch_and_add_8: |
| case Builtin::BI__sync_fetch_and_add_16: |
| case Builtin::BI__sync_fetch_and_sub: |
| case Builtin::BI__sync_fetch_and_sub_1: |
| case Builtin::BI__sync_fetch_and_sub_2: |
| case Builtin::BI__sync_fetch_and_sub_4: |
| case Builtin::BI__sync_fetch_and_sub_8: |
| case Builtin::BI__sync_fetch_and_sub_16: |
| case Builtin::BI__sync_fetch_and_or: |
| case Builtin::BI__sync_fetch_and_or_1: |
| case Builtin::BI__sync_fetch_and_or_2: |
| case Builtin::BI__sync_fetch_and_or_4: |
| case Builtin::BI__sync_fetch_and_or_8: |
| case Builtin::BI__sync_fetch_and_or_16: |
| case Builtin::BI__sync_fetch_and_and: |
| case Builtin::BI__sync_fetch_and_and_1: |
| case Builtin::BI__sync_fetch_and_and_2: |
| case Builtin::BI__sync_fetch_and_and_4: |
| case Builtin::BI__sync_fetch_and_and_8: |
| case Builtin::BI__sync_fetch_and_and_16: |
| case Builtin::BI__sync_fetch_and_xor: |
| case Builtin::BI__sync_fetch_and_xor_1: |
| case Builtin::BI__sync_fetch_and_xor_2: |
| case Builtin::BI__sync_fetch_and_xor_4: |
| case Builtin::BI__sync_fetch_and_xor_8: |
| case Builtin::BI__sync_fetch_and_xor_16: |
| case Builtin::BI__sync_add_and_fetch: |
| case Builtin::BI__sync_add_and_fetch_1: |
| case Builtin::BI__sync_add_and_fetch_2: |
| case Builtin::BI__sync_add_and_fetch_4: |
| case Builtin::BI__sync_add_and_fetch_8: |
| case Builtin::BI__sync_add_and_fetch_16: |
| case Builtin::BI__sync_sub_and_fetch: |
| case Builtin::BI__sync_sub_and_fetch_1: |
| case Builtin::BI__sync_sub_and_fetch_2: |
| case Builtin::BI__sync_sub_and_fetch_4: |
| case Builtin::BI__sync_sub_and_fetch_8: |
| case Builtin::BI__sync_sub_and_fetch_16: |
| case Builtin::BI__sync_and_and_fetch: |
| case Builtin::BI__sync_and_and_fetch_1: |
| case Builtin::BI__sync_and_and_fetch_2: |
| case Builtin::BI__sync_and_and_fetch_4: |
| case Builtin::BI__sync_and_and_fetch_8: |
| case Builtin::BI__sync_and_and_fetch_16: |
| case Builtin::BI__sync_or_and_fetch: |
| case Builtin::BI__sync_or_and_fetch_1: |
| case Builtin::BI__sync_or_and_fetch_2: |
| case Builtin::BI__sync_or_and_fetch_4: |
| case Builtin::BI__sync_or_and_fetch_8: |
| case Builtin::BI__sync_or_and_fetch_16: |
| case Builtin::BI__sync_xor_and_fetch: |
| case Builtin::BI__sync_xor_and_fetch_1: |
| case Builtin::BI__sync_xor_and_fetch_2: |
| case Builtin::BI__sync_xor_and_fetch_4: |
| case Builtin::BI__sync_xor_and_fetch_8: |
| case Builtin::BI__sync_xor_and_fetch_16: |
| case Builtin::BI__sync_val_compare_and_swap: |
| case Builtin::BI__sync_val_compare_and_swap_1: |
| case Builtin::BI__sync_val_compare_and_swap_2: |
| case Builtin::BI__sync_val_compare_and_swap_4: |
| case Builtin::BI__sync_val_compare_and_swap_8: |
| case Builtin::BI__sync_val_compare_and_swap_16: |
| case Builtin::BI__sync_bool_compare_and_swap: |
| case Builtin::BI__sync_bool_compare_and_swap_1: |
| case Builtin::BI__sync_bool_compare_and_swap_2: |
| case Builtin::BI__sync_bool_compare_and_swap_4: |
| case Builtin::BI__sync_bool_compare_and_swap_8: |
| case Builtin::BI__sync_bool_compare_and_swap_16: |
| case Builtin::BI__sync_lock_test_and_set: |
| case Builtin::BI__sync_lock_test_and_set_1: |
| case Builtin::BI__sync_lock_test_and_set_2: |
| case Builtin::BI__sync_lock_test_and_set_4: |
| case Builtin::BI__sync_lock_test_and_set_8: |
| case Builtin::BI__sync_lock_test_and_set_16: |
| case Builtin::BI__sync_lock_release: |
| case Builtin::BI__sync_lock_release_1: |
| case Builtin::BI__sync_lock_release_2: |
| case Builtin::BI__sync_lock_release_4: |
| case Builtin::BI__sync_lock_release_8: |
| case Builtin::BI__sync_lock_release_16: |
| case Builtin::BI__sync_swap: |
| case Builtin::BI__sync_swap_1: |
| case Builtin::BI__sync_swap_2: |
| case Builtin::BI__sync_swap_4: |
| case Builtin::BI__sync_swap_8: |
| case Builtin::BI__sync_swap_16: |
| return SemaBuiltinAtomicOverloaded(TheCallResult); |
| #define BUILTIN(ID, TYPE, ATTRS) |
| #define ATOMIC_BUILTIN(ID, TYPE, ATTRS) \ |
| case Builtin::BI##ID: \ |
| return SemaAtomicOpsOverloaded(TheCallResult, AtomicExpr::AO##ID); |
| #include "clang/Basic/Builtins.def" |
| case Builtin::BI__builtin_annotation: |
| if (SemaBuiltinAnnotation(*this, TheCall)) |
| return ExprError(); |
| break; |
| } |
| |
| // Since the target specific builtins for each arch overlap, only check those |
| // of the arch we are compiling for. |
| if (BuiltinID >= Builtin::FirstTSBuiltin) { |
| switch (Context.getTargetInfo().getTriple().getArch()) { |
| case llvm::Triple::arm: |
| case llvm::Triple::thumb: |
| if (CheckARMBuiltinFunctionCall(BuiltinID, TheCall)) |
| return ExprError(); |
| break; |
| case llvm::Triple::mips: |
| case llvm::Triple::mipsel: |
| case llvm::Triple::mips64: |
| case llvm::Triple::mips64el: |
| if (CheckMipsBuiltinFunctionCall(BuiltinID, TheCall)) |
| return ExprError(); |
| break; |
| default: |
| break; |
| } |
| } |
| |
| return TheCallResult; |
| } |
| |
| // Get the valid immediate range for the specified NEON type code. |
| static unsigned RFT(unsigned t, bool shift = false) { |
| NeonTypeFlags Type(t); |
| int IsQuad = Type.isQuad(); |
| switch (Type.getEltType()) { |
| case NeonTypeFlags::Int8: |
| case NeonTypeFlags::Poly8: |
| return shift ? 7 : (8 << IsQuad) - 1; |
| case NeonTypeFlags::Int16: |
| case NeonTypeFlags::Poly16: |
| return shift ? 15 : (4 << IsQuad) - 1; |
| case NeonTypeFlags::Int32: |
| return shift ? 31 : (2 << IsQuad) - 1; |
| case NeonTypeFlags::Int64: |
| return shift ? 63 : (1 << IsQuad) - 1; |
| case NeonTypeFlags::Float16: |
| assert(!shift && "cannot shift float types!"); |
| return (4 << IsQuad) - 1; |
| case NeonTypeFlags::Float32: |
| assert(!shift && "cannot shift float types!"); |
| return (2 << IsQuad) - 1; |
| } |
| llvm_unreachable("Invalid NeonTypeFlag!"); |
| } |
| |
| /// getNeonEltType - Return the QualType corresponding to the elements of |
| /// the vector type specified by the NeonTypeFlags. This is used to check |
| /// the pointer arguments for Neon load/store intrinsics. |
| static QualType getNeonEltType(NeonTypeFlags Flags, ASTContext &Context) { |
| switch (Flags.getEltType()) { |
| case NeonTypeFlags::Int8: |
| return Flags.isUnsigned() ? Context.UnsignedCharTy : Context.SignedCharTy; |
| case NeonTypeFlags::Int16: |
| return Flags.isUnsigned() ? Context.UnsignedShortTy : Context.ShortTy; |
| case NeonTypeFlags::Int32: |
| return Flags.isUnsigned() ? Context.UnsignedIntTy : Context.IntTy; |
| case NeonTypeFlags::Int64: |
| return Flags.isUnsigned() ? Context.UnsignedLongLongTy : Context.LongLongTy; |
| case NeonTypeFlags::Poly8: |
| return Context.SignedCharTy; |
| case NeonTypeFlags::Poly16: |
| return Context.ShortTy; |
| case NeonTypeFlags::Float16: |
| return Context.UnsignedShortTy; |
| case NeonTypeFlags::Float32: |
| return Context.FloatTy; |
| } |
| llvm_unreachable("Invalid NeonTypeFlag!"); |
| } |
| |
| bool Sema::CheckARMBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall) { |
| llvm::APSInt Result; |
| |
| uint64_t mask = 0; |
| unsigned TV = 0; |
| int PtrArgNum = -1; |
| bool HasConstPtr = false; |
| switch (BuiltinID) { |
| #define GET_NEON_OVERLOAD_CHECK |
| #include "clang/Basic/arm_neon.inc" |
| #undef GET_NEON_OVERLOAD_CHECK |
| } |
| |
| // For NEON intrinsics which are overloaded on vector element type, validate |
| // the immediate which specifies which variant to emit. |
| unsigned ImmArg = TheCall->getNumArgs()-1; |
| if (mask) { |
| if (SemaBuiltinConstantArg(TheCall, ImmArg, Result)) |
| return true; |
| |
| TV = Result.getLimitedValue(64); |
| if ((TV > 63) || (mask & (1ULL << TV)) == 0) |
| return Diag(TheCall->getLocStart(), diag::err_invalid_neon_type_code) |
| << TheCall->getArg(ImmArg)->getSourceRange(); |
| } |
| |
| if (PtrArgNum >= 0) { |
| // Check that pointer arguments have the specified type. |
| Expr *Arg = TheCall->getArg(PtrArgNum); |
| if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(Arg)) |
| Arg = ICE->getSubExpr(); |
| ExprResult RHS = DefaultFunctionArrayLvalueConversion(Arg); |
| QualType RHSTy = RHS.get()->getType(); |
| QualType EltTy = getNeonEltType(NeonTypeFlags(TV), Context); |
| if (HasConstPtr) |
| EltTy = EltTy.withConst(); |
| QualType LHSTy = Context.getPointerType(EltTy); |
| AssignConvertType ConvTy; |
| ConvTy = CheckSingleAssignmentConstraints(LHSTy, RHS); |
| if (RHS.isInvalid()) |
| return true; |
| if (DiagnoseAssignmentResult(ConvTy, Arg->getLocStart(), LHSTy, RHSTy, |
| RHS.get(), AA_Assigning)) |
| return true; |
| } |
| |
| // For NEON intrinsics which take an immediate value as part of the |
| // instruction, range check them here. |
| unsigned i = 0, l = 0, u = 0; |
| switch (BuiltinID) { |
| default: return false; |
| case ARM::BI__builtin_arm_ssat: i = 1; l = 1; u = 31; break; |
| case ARM::BI__builtin_arm_usat: i = 1; u = 31; break; |
| case ARM::BI__builtin_arm_vcvtr_f: |
| case ARM::BI__builtin_arm_vcvtr_d: i = 1; u = 1; break; |
| #define GET_NEON_IMMEDIATE_CHECK |
| #include "clang/Basic/arm_neon.inc" |
| #undef GET_NEON_IMMEDIATE_CHECK |
| }; |
| |
| // We can't check the value of a dependent argument. |
| if (TheCall->getArg(i)->isTypeDependent() || |
| TheCall->getArg(i)->isValueDependent()) |
| return false; |
| |
| // Check that the immediate argument is actually a constant. |
| if (SemaBuiltinConstantArg(TheCall, i, Result)) |
| return true; |
| |
| // Range check against the upper/lower values for this isntruction. |
| unsigned Val = Result.getZExtValue(); |
| if (Val < l || Val > (u + l)) |
| return Diag(TheCall->getLocStart(), diag::err_argument_invalid_range) |
| << l << u+l << TheCall->getArg(i)->getSourceRange(); |
| |
| // FIXME: VFP Intrinsics should error if VFP not present. |
| return false; |
| } |
| |
| bool Sema::CheckMipsBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall) { |
| unsigned i = 0, l = 0, u = 0; |
| switch (BuiltinID) { |
| default: return false; |
| case Mips::BI__builtin_mips_wrdsp: i = 1; l = 0; u = 63; break; |
| case Mips::BI__builtin_mips_rddsp: i = 0; l = 0; u = 63; break; |
| case Mips::BI__builtin_mips_append: i = 2; l = 0; u = 31; break; |
| case Mips::BI__builtin_mips_balign: i = 2; l = 0; u = 3; break; |
| case Mips::BI__builtin_mips_precr_sra_ph_w: i = 2; l = 0; u = 31; break; |
| case Mips::BI__builtin_mips_precr_sra_r_ph_w: i = 2; l = 0; u = 31; break; |
| case Mips::BI__builtin_mips_prepend: i = 2; l = 0; u = 31; break; |
| }; |
| |
| // We can't check the value of a dependent argument. |
| if (TheCall->getArg(i)->isTypeDependent() || |
| TheCall->getArg(i)->isValueDependent()) |
| return false; |
| |
| // Check that the immediate argument is actually a constant. |
| llvm::APSInt Result; |
| if (SemaBuiltinConstantArg(TheCall, i, Result)) |
| return true; |
| |
| // Range check against the upper/lower values for this instruction. |
| unsigned Val = Result.getZExtValue(); |
| if (Val < l || Val > u) |
| return Diag(TheCall->getLocStart(), diag::err_argument_invalid_range) |
| << l << u << TheCall->getArg(i)->getSourceRange(); |
| |
| return false; |
| } |
| |
| /// Given a FunctionDecl's FormatAttr, attempts to populate the FomatStringInfo |
| /// parameter with the FormatAttr's correct format_idx and firstDataArg. |
| /// Returns true when the format fits the function and the FormatStringInfo has |
| /// been populated. |
| bool Sema::getFormatStringInfo(const FormatAttr *Format, bool IsCXXMember, |
| FormatStringInfo *FSI) { |
| FSI->HasVAListArg = Format->getFirstArg() == 0; |
| FSI->FormatIdx = Format->getFormatIdx() - 1; |
| FSI->FirstDataArg = FSI->HasVAListArg ? 0 : Format->getFirstArg() - 1; |
| |
| // The way the format attribute works in GCC, the implicit this argument |
| // of member functions is counted. However, it doesn't appear in our own |
| // lists, so decrement format_idx in that case. |
| if (IsCXXMember) { |
| if(FSI->FormatIdx == 0) |
| return false; |
| --FSI->FormatIdx; |
| if (FSI->FirstDataArg != 0) |
| --FSI->FirstDataArg; |
| } |
| return true; |
| } |
| |
| /// Handles the checks for format strings, non-POD arguments to vararg |
| /// functions, and NULL arguments passed to non-NULL parameters. |
| void Sema::checkCall(NamedDecl *FDecl, Expr **Args, |
| unsigned NumArgs, |
| unsigned NumProtoArgs, |
| bool IsMemberFunction, |
| SourceLocation Loc, |
| SourceRange Range, |
| VariadicCallType CallType) { |
| // FIXME: This mechanism should be abstracted to be less fragile and |
| // more efficient. For example, just map function ids to custom |
| // handlers. |
| |
| // Printf and scanf checking. |
| bool HandledFormatString = false; |
| for (specific_attr_iterator<FormatAttr> |
| I = FDecl->specific_attr_begin<FormatAttr>(), |
| E = FDecl->specific_attr_end<FormatAttr>(); I != E ; ++I) |
| if (CheckFormatArguments(*I, Args, NumArgs, IsMemberFunction, CallType, |
| Loc, Range)) |
| HandledFormatString = true; |
| |
| // Refuse POD arguments that weren't caught by the format string |
| // checks above. |
| if (!HandledFormatString && CallType != VariadicDoesNotApply) |
| for (unsigned ArgIdx = NumProtoArgs; ArgIdx < NumArgs; ++ArgIdx) |
| variadicArgumentPODCheck(Args[ArgIdx], CallType); |
| |
| for (specific_attr_iterator<NonNullAttr> |
| I = FDecl->specific_attr_begin<NonNullAttr>(), |
| E = FDecl->specific_attr_end<NonNullAttr>(); I != E; ++I) |
| CheckNonNullArguments(*I, Args, Loc); |
| |
| // Type safety checking. |
| for (specific_attr_iterator<ArgumentWithTypeTagAttr> |
| i = FDecl->specific_attr_begin<ArgumentWithTypeTagAttr>(), |
| e = FDecl->specific_attr_end<ArgumentWithTypeTagAttr>(); i != e; ++i) { |
| CheckArgumentWithTypeTag(*i, Args); |
| } |
| } |
| |
| /// CheckConstructorCall - Check a constructor call for correctness and safety |
| /// properties not enforced by the C type system. |
| void Sema::CheckConstructorCall(FunctionDecl *FDecl, Expr **Args, |
| unsigned NumArgs, |
| const FunctionProtoType *Proto, |
| SourceLocation Loc) { |
| VariadicCallType CallType = |
| Proto->isVariadic() ? VariadicConstructor : VariadicDoesNotApply; |
| checkCall(FDecl, Args, NumArgs, Proto->getNumArgs(), |
| /*IsMemberFunction=*/true, Loc, SourceRange(), CallType); |
| } |
| |
| /// CheckFunctionCall - Check a direct function call for various correctness |
| /// and safety properties not strictly enforced by the C type system. |
| bool Sema::CheckFunctionCall(FunctionDecl *FDecl, CallExpr *TheCall, |
| const FunctionProtoType *Proto) { |
| bool IsMemberFunction = isa<CXXMemberCallExpr>(TheCall); |
| VariadicCallType CallType = getVariadicCallType(FDecl, Proto, |
| TheCall->getCallee()); |
| unsigned NumProtoArgs = Proto ? Proto->getNumArgs() : 0; |
| checkCall(FDecl, TheCall->getArgs(), TheCall->getNumArgs(), NumProtoArgs, |
| IsMemberFunction, TheCall->getRParenLoc(), |
| TheCall->getCallee()->getSourceRange(), CallType); |
| |
| IdentifierInfo *FnInfo = FDecl->getIdentifier(); |
| // None of the checks below are needed for functions that don't have |
| // simple names (e.g., C++ conversion functions). |
| if (!FnInfo) |
| return false; |
| |
| unsigned CMId = FDecl->getMemoryFunctionKind(); |
| if (CMId == 0) |
| return false; |
| |
| // Handle memory setting and copying functions. |
| if (CMId == Builtin::BIstrlcpy || CMId == Builtin::BIstrlcat) |
| CheckStrlcpycatArguments(TheCall, FnInfo); |
| else if (CMId == Builtin::BIstrncat) |
| CheckStrncatArguments(TheCall, FnInfo); |
| else |
| CheckMemaccessArguments(TheCall, CMId, FnInfo); |
| |
| return false; |
| } |
| |
| bool Sema::CheckObjCMethodCall(ObjCMethodDecl *Method, SourceLocation lbrac, |
| Expr **Args, unsigned NumArgs) { |
| VariadicCallType CallType = |
| Method->isVariadic() ? VariadicMethod : VariadicDoesNotApply; |
| |
| checkCall(Method, Args, NumArgs, Method->param_size(), |
| /*IsMemberFunction=*/false, |
| lbrac, Method->getSourceRange(), CallType); |
| |
| return false; |
| } |
| |
| bool Sema::CheckBlockCall(NamedDecl *NDecl, CallExpr *TheCall, |
| const FunctionProtoType *Proto) { |
| const VarDecl *V = dyn_cast<VarDecl>(NDecl); |
| if (!V) |
| return false; |
| |
| QualType Ty = V->getType(); |
| if (!Ty->isBlockPointerType()) |
| return false; |
| |
| VariadicCallType CallType = |
| Proto && Proto->isVariadic() ? VariadicBlock : VariadicDoesNotApply ; |
| unsigned NumProtoArgs = Proto ? Proto->getNumArgs() : 0; |
| |
| checkCall(NDecl, TheCall->getArgs(), TheCall->getNumArgs(), |
| NumProtoArgs, /*IsMemberFunction=*/false, |
| TheCall->getRParenLoc(), |
| TheCall->getCallee()->getSourceRange(), CallType); |
| |
| return false; |
| } |
| |
| ExprResult Sema::SemaAtomicOpsOverloaded(ExprResult TheCallResult, |
| AtomicExpr::AtomicOp Op) { |
| CallExpr *TheCall = cast<CallExpr>(TheCallResult.get()); |
| DeclRefExpr *DRE =cast<DeclRefExpr>(TheCall->getCallee()->IgnoreParenCasts()); |
| |
| // All these operations take one of the following forms: |
| enum { |
| // C __c11_atomic_init(A *, C) |
| Init, |
| // C __c11_atomic_load(A *, int) |
| Load, |
| // void __atomic_load(A *, CP, int) |
| Copy, |
| // C __c11_atomic_add(A *, M, int) |
| Arithmetic, |
| // C __atomic_exchange_n(A *, CP, int) |
| Xchg, |
| // void __atomic_exchange(A *, C *, CP, int) |
| GNUXchg, |
| // bool __c11_atomic_compare_exchange_strong(A *, C *, CP, int, int) |
| C11CmpXchg, |
| // bool __atomic_compare_exchange(A *, C *, CP, bool, int, int) |
| GNUCmpXchg |
| } Form = Init; |
| const unsigned NumArgs[] = { 2, 2, 3, 3, 3, 4, 5, 6 }; |
| const unsigned NumVals[] = { 1, 0, 1, 1, 1, 2, 2, 3 }; |
| // where: |
| // C is an appropriate type, |
| // A is volatile _Atomic(C) for __c11 builtins and is C for GNU builtins, |
| // CP is C for __c11 builtins and GNU _n builtins and is C * otherwise, |
| // M is C if C is an integer, and ptrdiff_t if C is a pointer, and |
| // the int parameters are for orderings. |
| |
| assert(AtomicExpr::AO__c11_atomic_init == 0 && |
| AtomicExpr::AO__c11_atomic_fetch_xor + 1 == AtomicExpr::AO__atomic_load |
| && "need to update code for modified C11 atomics"); |
| bool IsC11 = Op >= AtomicExpr::AO__c11_atomic_init && |
| Op <= AtomicExpr::AO__c11_atomic_fetch_xor; |
| bool IsN = Op == AtomicExpr::AO__atomic_load_n || |
| Op == AtomicExpr::AO__atomic_store_n || |
| Op == AtomicExpr::AO__atomic_exchange_n || |
| Op == AtomicExpr::AO__atomic_compare_exchange_n; |
| bool IsAddSub = false; |
| |
| switch (Op) { |
| case AtomicExpr::AO__c11_atomic_init: |
| Form = Init; |
| break; |
| |
| case AtomicExpr::AO__c11_atomic_load: |
| case AtomicExpr::AO__atomic_load_n: |
| Form = Load; |
| break; |
| |
| case AtomicExpr::AO__c11_atomic_store: |
| case AtomicExpr::AO__atomic_load: |
| case AtomicExpr::AO__atomic_store: |
| case AtomicExpr::AO__atomic_store_n: |
| Form = Copy; |
| break; |
| |
| case AtomicExpr::AO__c11_atomic_fetch_add: |
| case AtomicExpr::AO__c11_atomic_fetch_sub: |
| case AtomicExpr::AO__atomic_fetch_add: |
| case AtomicExpr::AO__atomic_fetch_sub: |
| case AtomicExpr::AO__atomic_add_fetch: |
| case AtomicExpr::AO__atomic_sub_fetch: |
| IsAddSub = true; |
| // Fall through. |
| case AtomicExpr::AO__c11_atomic_fetch_and: |
| case AtomicExpr::AO__c11_atomic_fetch_or: |
| case AtomicExpr::AO__c11_atomic_fetch_xor: |
| case AtomicExpr::AO__atomic_fetch_and: |
| case AtomicExpr::AO__atomic_fetch_or: |
| case AtomicExpr::AO__atomic_fetch_xor: |
| case AtomicExpr::AO__atomic_fetch_nand: |
| case AtomicExpr::AO__atomic_and_fetch: |
| case AtomicExpr::AO__atomic_or_fetch: |
| case AtomicExpr::AO__atomic_xor_fetch: |
| case AtomicExpr::AO__atomic_nand_fetch: |
| Form = Arithmetic; |
| break; |
| |
| case AtomicExpr::AO__c11_atomic_exchange: |
| case AtomicExpr::AO__atomic_exchange_n: |
| Form = Xchg; |
| break; |
| |
| case AtomicExpr::AO__atomic_exchange: |
| Form = GNUXchg; |
| break; |
| |
| case AtomicExpr::AO__c11_atomic_compare_exchange_strong: |
| case AtomicExpr::AO__c11_atomic_compare_exchange_weak: |
| Form = C11CmpXchg; |
| break; |
| |
| case AtomicExpr::AO__atomic_compare_exchange: |
| case AtomicExpr::AO__atomic_compare_exchange_n: |
| Form = GNUCmpXchg; |
| break; |
| } |
| |
| // Check we have the right number of arguments. |
| if (TheCall->getNumArgs() < NumArgs[Form]) { |
| Diag(TheCall->getLocEnd(), diag::err_typecheck_call_too_few_args) |
| << 0 << NumArgs[Form] << TheCall->getNumArgs() |
| << TheCall->getCallee()->getSourceRange(); |
| return ExprError(); |
| } else if (TheCall->getNumArgs() > NumArgs[Form]) { |
| Diag(TheCall->getArg(NumArgs[Form])->getLocStart(), |
| diag::err_typecheck_call_too_many_args) |
| << 0 << NumArgs[Form] << TheCall->getNumArgs() |
| << TheCall->getCallee()->getSourceRange(); |
| return ExprError(); |
| } |
| |
| // Inspect the first argument of the atomic operation. |
| Expr *Ptr = TheCall->getArg(0); |
| Ptr = DefaultFunctionArrayLvalueConversion(Ptr).get(); |
| const PointerType *pointerType = Ptr->getType()->getAs<PointerType>(); |
| if (!pointerType) { |
| Diag(DRE->getLocStart(), diag::err_atomic_builtin_must_be_pointer) |
| << Ptr->getType() << Ptr->getSourceRange(); |
| return ExprError(); |
| } |
| |
| // For a __c11 builtin, this should be a pointer to an _Atomic type. |
| QualType AtomTy = pointerType->getPointeeType(); // 'A' |
| QualType ValType = AtomTy; // 'C' |
| if (IsC11) { |
| if (!AtomTy->isAtomicType()) { |
| Diag(DRE->getLocStart(), diag::err_atomic_op_needs_atomic) |
| << Ptr->getType() << Ptr->getSourceRange(); |
| return ExprError(); |
| } |
| ValType = AtomTy->getAs<AtomicType>()->getValueType(); |
| } |
| |
| // For an arithmetic operation, the implied arithmetic must be well-formed. |
| if (Form == Arithmetic) { |
| // gcc does not enforce these rules for GNU atomics, but we do so for sanity. |
| if (IsAddSub && !ValType->isIntegerType() && !ValType->isPointerType()) { |
| Diag(DRE->getLocStart(), diag::err_atomic_op_needs_atomic_int_or_ptr) |
| << IsC11 << Ptr->getType() << Ptr->getSourceRange(); |
| return ExprError(); |
| } |
| if (!IsAddSub && !ValType->isIntegerType()) { |
| Diag(DRE->getLocStart(), diag::err_atomic_op_bitwise_needs_atomic_int) |
| << IsC11 << Ptr->getType() << Ptr->getSourceRange(); |
| return ExprError(); |
| } |
| } else if (IsN && !ValType->isIntegerType() && !ValType->isPointerType()) { |
| // For __atomic_*_n operations, the value type must be a scalar integral or |
| // pointer type which is 1, 2, 4, 8 or 16 bytes in length. |
| Diag(DRE->getLocStart(), diag::err_atomic_op_needs_atomic_int_or_ptr) |
| << IsC11 << Ptr->getType() << Ptr->getSourceRange(); |
| return ExprError(); |
| } |
| |
| if (!IsC11 && !AtomTy.isTriviallyCopyableType(Context)) { |
| // For GNU atomics, require a trivially-copyable type. This is not part of |
| // the GNU atomics specification, but we enforce it for sanity. |
| Diag(DRE->getLocStart(), diag::err_atomic_op_needs_trivial_copy) |
| << Ptr->getType() << Ptr->getSourceRange(); |
| return ExprError(); |
| } |
| |
| // FIXME: For any builtin other than a load, the ValType must not be |
| // const-qualified. |
| |
| switch (ValType.getObjCLifetime()) { |
| case Qualifiers::OCL_None: |
| case Qualifiers::OCL_ExplicitNone: |
| // okay |
| break; |
| |
| case Qualifiers::OCL_Weak: |
| case Qualifiers::OCL_Strong: |
| case Qualifiers::OCL_Autoreleasing: |
| // FIXME: Can this happen? By this point, ValType should be known |
| // to be trivially copyable. |
| Diag(DRE->getLocStart(), diag::err_arc_atomic_ownership) |
| << ValType << Ptr->getSourceRange(); |
| return ExprError(); |
| } |
| |
| QualType ResultType = ValType; |
| if (Form == Copy || Form == GNUXchg || Form == Init) |
| ResultType = Context.VoidTy; |
| else if (Form == C11CmpXchg || Form == GNUCmpXchg) |
| ResultType = Context.BoolTy; |
| |
| // The type of a parameter passed 'by value'. In the GNU atomics, such |
| // arguments are actually passed as pointers. |
| QualType ByValType = ValType; // 'CP' |
| if (!IsC11 && !IsN) |
| ByValType = Ptr->getType(); |
| |
| // The first argument --- the pointer --- has a fixed type; we |
| // deduce the types of the rest of the arguments accordingly. Walk |
| // the remaining arguments, converting them to the deduced value type. |
| for (unsigned i = 1; i != NumArgs[Form]; ++i) { |
| QualType Ty; |
| if (i < NumVals[Form] + 1) { |
| switch (i) { |
| case 1: |
| // The second argument is the non-atomic operand. For arithmetic, this |
| // is always passed by value, and for a compare_exchange it is always |
| // passed by address. For the rest, GNU uses by-address and C11 uses |
| // by-value. |
| assert(Form != Load); |
| if (Form == Init || (Form == Arithmetic && ValType->isIntegerType())) |
| Ty = ValType; |
| else if (Form == Copy || Form == Xchg) |
| Ty = ByValType; |
| else if (Form == Arithmetic) |
| Ty = Context.getPointerDiffType(); |
| else |
| Ty = Context.getPointerType(ValType.getUnqualifiedType()); |
| break; |
| case 2: |
| // The third argument to compare_exchange / GNU exchange is a |
| // (pointer to a) desired value. |
| Ty = ByValType; |
| break; |
| case 3: |
| // The fourth argument to GNU compare_exchange is a 'weak' flag. |
| Ty = Context.BoolTy; |
| break; |
| } |
| } else { |
| // The order(s) are always converted to int. |
| Ty = Context.IntTy; |
| } |
| |
| InitializedEntity Entity = |
| InitializedEntity::InitializeParameter(Context, Ty, false); |
| ExprResult Arg = TheCall->getArg(i); |
| Arg = PerformCopyInitialization(Entity, SourceLocation(), Arg); |
| if (Arg.isInvalid()) |
| return true; |
| TheCall->setArg(i, Arg.get()); |
| } |
| |
| // Permute the arguments into a 'consistent' order. |
| SmallVector<Expr*, 5> SubExprs; |
| SubExprs.push_back(Ptr); |
| switch (Form) { |
| case Init: |
| // Note, AtomicExpr::getVal1() has a special case for this atomic. |
| SubExprs.push_back(TheCall->getArg(1)); // Val1 |
| break; |
| case Load: |
| SubExprs.push_back(TheCall->getArg(1)); // Order |
| break; |
| case Copy: |
| case Arithmetic: |
| case Xchg: |
| SubExprs.push_back(TheCall->getArg(2)); // Order |
| SubExprs.push_back(TheCall->getArg(1)); // Val1 |
| break; |
| case GNUXchg: |
| // Note, AtomicExpr::getVal2() has a special case for this atomic. |
| SubExprs.push_back(TheCall->getArg(3)); // Order |
| SubExprs.push_back(TheCall->getArg(1)); // Val1 |
| SubExprs.push_back(TheCall->getArg(2)); // Val2 |
| break; |
| case C11CmpXchg: |
| SubExprs.push_back(TheCall->getArg(3)); // Order |
| SubExprs.push_back(TheCall->getArg(1)); // Val1 |
| SubExprs.push_back(TheCall->getArg(4)); // OrderFail |
| SubExprs.push_back(TheCall->getArg(2)); // Val2 |
| break; |
| case GNUCmpXchg: |
| SubExprs.push_back(TheCall->getArg(4)); // Order |
| SubExprs.push_back(TheCall->getArg(1)); // Val1 |
| SubExprs.push_back(TheCall->getArg(5)); // OrderFail |
| SubExprs.push_back(TheCall->getArg(2)); // Val2 |
| SubExprs.push_back(TheCall->getArg(3)); // Weak |
| break; |
| } |
| |
| return Owned(new (Context) AtomicExpr(TheCall->getCallee()->getLocStart(), |
| SubExprs, ResultType, Op, |
| TheCall->getRParenLoc())); |
| } |
| |
| |
| /// checkBuiltinArgument - Given a call to a builtin function, perform |
| /// normal type-checking on the given argument, updating the call in |
| /// place. This is useful when a builtin function requires custom |
| /// type-checking for some of its arguments but not necessarily all of |
| /// them. |
| /// |
| /// Returns true on error. |
| static bool checkBuiltinArgument(Sema &S, CallExpr *E, unsigned ArgIndex) { |
| FunctionDecl *Fn = E->getDirectCallee(); |
| assert(Fn && "builtin call without direct callee!"); |
| |
| ParmVarDecl *Param = Fn->getParamDecl(ArgIndex); |
| InitializedEntity Entity = |
| InitializedEntity::InitializeParameter(S.Context, Param); |
| |
| ExprResult Arg = E->getArg(0); |
| Arg = S.PerformCopyInitialization(Entity, SourceLocation(), Arg); |
| if (Arg.isInvalid()) |
| return true; |
| |
| E->setArg(ArgIndex, Arg.take()); |
| return false; |
| } |
| |
| /// SemaBuiltinAtomicOverloaded - We have a call to a function like |
| /// __sync_fetch_and_add, which is an overloaded function based on the pointer |
| /// type of its first argument. The main ActOnCallExpr routines have already |
| /// promoted the types of arguments because all of these calls are prototyped as |
| /// void(...). |
| /// |
| /// This function goes through and does final semantic checking for these |
| /// builtins, |
| ExprResult |
| Sema::SemaBuiltinAtomicOverloaded(ExprResult TheCallResult) { |
| CallExpr *TheCall = (CallExpr *)TheCallResult.get(); |
| DeclRefExpr *DRE =cast<DeclRefExpr>(TheCall->getCallee()->IgnoreParenCasts()); |
| FunctionDecl *FDecl = cast<FunctionDecl>(DRE->getDecl()); |
| |
| // Ensure that we have at least one argument to do type inference from. |
| if (TheCall->getNumArgs() < 1) { |
| Diag(TheCall->getLocEnd(), diag::err_typecheck_call_too_few_args_at_least) |
| << 0 << 1 << TheCall->getNumArgs() |
| << TheCall->getCallee()->getSourceRange(); |
| return ExprError(); |
| } |
| |
| // Inspect the first argument of the atomic builtin. This should always be |
| // a pointer type, whose element is an integral scalar or pointer type. |
| // Because it is a pointer type, we don't have to worry about any implicit |
| // casts here. |
| // FIXME: We don't allow floating point scalars as input. |
| Expr *FirstArg = TheCall->getArg(0); |
| ExprResult FirstArgResult = DefaultFunctionArrayLvalueConversion(FirstArg); |
| if (FirstArgResult.isInvalid()) |
| return ExprError(); |
| FirstArg = FirstArgResult.take(); |
| TheCall->setArg(0, FirstArg); |
| |
| const PointerType *pointerType = FirstArg->getType()->getAs<PointerType>(); |
| if (!pointerType) { |
| Diag(DRE->getLocStart(), diag::err_atomic_builtin_must_be_pointer) |
| << FirstArg->getType() << FirstArg->getSourceRange(); |
| return ExprError(); |
| } |
| |
| QualType ValType = pointerType->getPointeeType(); |
| if (!ValType->isIntegerType() && !ValType->isAnyPointerType() && |
| !ValType->isBlockPointerType()) { |
| Diag(DRE->getLocStart(), diag::err_atomic_builtin_must_be_pointer_intptr) |
| << FirstArg->getType() << FirstArg->getSourceRange(); |
| return ExprError(); |
| } |
| |
| switch (ValType.getObjCLifetime()) { |
| case Qualifiers::OCL_None: |
| case Qualifiers::OCL_ExplicitNone: |
| // okay |
| break; |
| |
| case Qualifiers::OCL_Weak: |
| case Qualifiers::OCL_Strong: |
| case Qualifiers::OCL_Autoreleasing: |
| Diag(DRE->getLocStart(), diag::err_arc_atomic_ownership) |
| << ValType << FirstArg->getSourceRange(); |
| return ExprError(); |
| } |
| |
| // Strip any qualifiers off ValType. |
| ValType = ValType.getUnqualifiedType(); |
| |
| // The majority of builtins return a value, but a few have special return |
| // types, so allow them to override appropriately below. |
| QualType ResultType = ValType; |
| |
| // We need to figure out which concrete builtin this maps onto. For example, |
| // __sync_fetch_and_add with a 2 byte object turns into |
| // __sync_fetch_and_add_2. |
| #define BUILTIN_ROW(x) \ |
| { Builtin::BI##x##_1, Builtin::BI##x##_2, Builtin::BI##x##_4, \ |
| Builtin::BI##x##_8, Builtin::BI##x##_16 } |
| |
| static const unsigned BuiltinIndices[][5] = { |
| BUILTIN_ROW(__sync_fetch_and_add), |
| BUILTIN_ROW(__sync_fetch_and_sub), |
| BUILTIN_ROW(__sync_fetch_and_or), |
| BUILTIN_ROW(__sync_fetch_and_and), |
| BUILTIN_ROW(__sync_fetch_and_xor), |
| |
| BUILTIN_ROW(__sync_add_and_fetch), |
| BUILTIN_ROW(__sync_sub_and_fetch), |
| BUILTIN_ROW(__sync_and_and_fetch), |
| BUILTIN_ROW(__sync_or_and_fetch), |
| BUILTIN_ROW(__sync_xor_and_fetch), |
| |
| BUILTIN_ROW(__sync_val_compare_and_swap), |
| BUILTIN_ROW(__sync_bool_compare_and_swap), |
| BUILTIN_ROW(__sync_lock_test_and_set), |
| BUILTIN_ROW(__sync_lock_release), |
| BUILTIN_ROW(__sync_swap) |
| }; |
| #undef BUILTIN_ROW |
| |
| // Determine the index of the size. |
| unsigned SizeIndex; |
| switch (Context.getTypeSizeInChars(ValType).getQuantity()) { |
| case 1: SizeIndex = 0; break; |
| case 2: SizeIndex = 1; break; |
| case 4: SizeIndex = 2; break; |
| case 8: SizeIndex = 3; break; |
| case 16: SizeIndex = 4; break; |
| default: |
| Diag(DRE->getLocStart(), diag::err_atomic_builtin_pointer_size) |
| << FirstArg->getType() << FirstArg->getSourceRange(); |
| return ExprError(); |
| } |
| |
| // Each of these builtins has one pointer argument, followed by some number of |
| // values (0, 1 or 2) followed by a potentially empty varags list of stuff |
| // that we ignore. Find out which row of BuiltinIndices to read from as well |
| // as the number of fixed args. |
| unsigned BuiltinID = FDecl->getBuiltinID(); |
| unsigned BuiltinIndex, NumFixed = 1; |
| switch (BuiltinID) { |
| default: llvm_unreachable("Unknown overloaded atomic builtin!"); |
| case Builtin::BI__sync_fetch_and_add: |
| case Builtin::BI__sync_fetch_and_add_1: |
| case Builtin::BI__sync_fetch_and_add_2: |
| case Builtin::BI__sync_fetch_and_add_4: |
| case Builtin::BI__sync_fetch_and_add_8: |
| case Builtin::BI__sync_fetch_and_add_16: |
| BuiltinIndex = 0; |
| break; |
| |
| case Builtin::BI__sync_fetch_and_sub: |
| case Builtin::BI__sync_fetch_and_sub_1: |
| case Builtin::BI__sync_fetch_and_sub_2: |
| case Builtin::BI__sync_fetch_and_sub_4: |
| case Builtin::BI__sync_fetch_and_sub_8: |
| case Builtin::BI__sync_fetch_and_sub_16: |
| BuiltinIndex = 1; |
| break; |
| |
| case Builtin::BI__sync_fetch_and_or: |
| case Builtin::BI__sync_fetch_and_or_1: |
| case Builtin::BI__sync_fetch_and_or_2: |
| case Builtin::BI__sync_fetch_and_or_4: |
| case Builtin::BI__sync_fetch_and_or_8: |
| case Builtin::BI__sync_fetch_and_or_16: |
| BuiltinIndex = 2; |
| break; |
| |
| case Builtin::BI__sync_fetch_and_and: |
| case Builtin::BI__sync_fetch_and_and_1: |
| case Builtin::BI__sync_fetch_and_and_2: |
| case Builtin::BI__sync_fetch_and_and_4: |
| case Builtin::BI__sync_fetch_and_and_8: |
| case Builtin::BI__sync_fetch_and_and_16: |
| BuiltinIndex = 3; |
| break; |
| |
| case Builtin::BI__sync_fetch_and_xor: |
| case Builtin::BI__sync_fetch_and_xor_1: |
| case Builtin::BI__sync_fetch_and_xor_2: |
| case Builtin::BI__sync_fetch_and_xor_4: |
| case Builtin::BI__sync_fetch_and_xor_8: |
| case Builtin::BI__sync_fetch_and_xor_16: |
| BuiltinIndex = 4; |
| break; |
| |
| case Builtin::BI__sync_add_and_fetch: |
| case Builtin::BI__sync_add_and_fetch_1: |
| case Builtin::BI__sync_add_and_fetch_2: |
| case Builtin::BI__sync_add_and_fetch_4: |
| case Builtin::BI__sync_add_and_fetch_8: |
| case Builtin::BI__sync_add_and_fetch_16: |
| BuiltinIndex = 5; |
| break; |
| |
| case Builtin::BI__sync_sub_and_fetch: |
| case Builtin::BI__sync_sub_and_fetch_1: |
| case Builtin::BI__sync_sub_and_fetch_2: |
| case Builtin::BI__sync_sub_and_fetch_4: |
| case Builtin::BI__sync_sub_and_fetch_8: |
| case Builtin::BI__sync_sub_and_fetch_16: |
| BuiltinIndex = 6; |
| break; |
| |
| case Builtin::BI__sync_and_and_fetch: |
| case Builtin::BI__sync_and_and_fetch_1: |
| case Builtin::BI__sync_and_and_fetch_2: |
| case Builtin::BI__sync_and_and_fetch_4: |
| case Builtin::BI__sync_and_and_fetch_8: |
| case Builtin::BI__sync_and_and_fetch_16: |
| BuiltinIndex = 7; |
| break; |
| |
| case Builtin::BI__sync_or_and_fetch: |
| case Builtin::BI__sync_or_and_fetch_1: |
| case Builtin::BI__sync_or_and_fetch_2: |
| case Builtin::BI__sync_or_and_fetch_4: |
| case Builtin::BI__sync_or_and_fetch_8: |
| case Builtin::BI__sync_or_and_fetch_16: |
| BuiltinIndex = 8; |
| break; |
| |
| case Builtin::BI__sync_xor_and_fetch: |
| case Builtin::BI__sync_xor_and_fetch_1: |
| case Builtin::BI__sync_xor_and_fetch_2: |
| case Builtin::BI__sync_xor_and_fetch_4: |
| case Builtin::BI__sync_xor_and_fetch_8: |
| case Builtin::BI__sync_xor_and_fetch_16: |
| BuiltinIndex = 9; |
| break; |
| |
| case Builtin::BI__sync_val_compare_and_swap: |
| case Builtin::BI__sync_val_compare_and_swap_1: |
| case Builtin::BI__sync_val_compare_and_swap_2: |
| case Builtin::BI__sync_val_compare_and_swap_4: |
| case Builtin::BI__sync_val_compare_and_swap_8: |
| case Builtin::BI__sync_val_compare_and_swap_16: |
| BuiltinIndex = 10; |
| NumFixed = 2; |
| break; |
| |
| case Builtin::BI__sync_bool_compare_and_swap: |
| case Builtin::BI__sync_bool_compare_and_swap_1: |
| case Builtin::BI__sync_bool_compare_and_swap_2: |
| case Builtin::BI__sync_bool_compare_and_swap_4: |
| case Builtin::BI__sync_bool_compare_and_swap_8: |
| case Builtin::BI__sync_bool_compare_and_swap_16: |
| BuiltinIndex = 11; |
| NumFixed = 2; |
| ResultType = Context.BoolTy; |
| break; |
| |
| case Builtin::BI__sync_lock_test_and_set: |
| case Builtin::BI__sync_lock_test_and_set_1: |
| case Builtin::BI__sync_lock_test_and_set_2: |
| case Builtin::BI__sync_lock_test_and_set_4: |
| case Builtin::BI__sync_lock_test_and_set_8: |
| case Builtin::BI__sync_lock_test_and_set_16: |
| BuiltinIndex = 12; |
| break; |
| |
| case Builtin::BI__sync_lock_release: |
| case Builtin::BI__sync_lock_release_1: |
| case Builtin::BI__sync_lock_release_2: |
| case Builtin::BI__sync_lock_release_4: |
| case Builtin::BI__sync_lock_release_8: |
| case Builtin::BI__sync_lock_release_16: |
| BuiltinIndex = 13; |
| NumFixed = 0; |
| ResultType = Context.VoidTy; |
| break; |
| |
| case Builtin::BI__sync_swap: |
| case Builtin::BI__sync_swap_1: |
| case Builtin::BI__sync_swap_2: |
| case Builtin::BI__sync_swap_4: |
| case Builtin::BI__sync_swap_8: |
| case Builtin::BI__sync_swap_16: |
| BuiltinIndex = 14; |
| break; |
| } |
| |
| // Now that we know how many fixed arguments we expect, first check that we |
| // have at least that many. |
| if (TheCall->getNumArgs() < 1+NumFixed) { |
| Diag(TheCall->getLocEnd(), diag::err_typecheck_call_too_few_args_at_least) |
| << 0 << 1+NumFixed << TheCall->getNumArgs() |
| << TheCall->getCallee()->getSourceRange(); |
| return ExprError(); |
| } |
| |
| // Get the decl for the concrete builtin from this, we can tell what the |
| // concrete integer type we should convert to is. |
| unsigned NewBuiltinID = BuiltinIndices[BuiltinIndex][SizeIndex]; |
| const char *NewBuiltinName = Context.BuiltinInfo.GetName(NewBuiltinID); |
| IdentifierInfo *NewBuiltinII = PP.getIdentifierInfo(NewBuiltinName); |
| FunctionDecl *NewBuiltinDecl = |
| cast<FunctionDecl>(LazilyCreateBuiltin(NewBuiltinII, NewBuiltinID, |
| TUScope, false, DRE->getLocStart())); |
| |
| // The first argument --- the pointer --- has a fixed type; we |
| // deduce the types of the rest of the arguments accordingly. Walk |
| // the remaining arguments, converting them to the deduced value type. |
| for (unsigned i = 0; i != NumFixed; ++i) { |
| ExprResult Arg = TheCall->getArg(i+1); |
| |
| // GCC does an implicit conversion to the pointer or integer ValType. This |
| // can fail in some cases (1i -> int**), check for this error case now. |
| // Initialize the argument. |
| InitializedEntity Entity = InitializedEntity::InitializeParameter(Context, |
| ValType, /*consume*/ false); |
| Arg = PerformCopyInitialization(Entity, SourceLocation(), Arg); |
| if (Arg.isInvalid()) |
| return ExprError(); |
| |
| // Okay, we have something that *can* be converted to the right type. Check |
| // to see if there is a potentially weird extension going on here. This can |
| // happen when you do an atomic operation on something like an char* and |
| // pass in 42. The 42 gets converted to char. This is even more strange |
| // for things like 45.123 -> char, etc. |
| // FIXME: Do this check. |
| TheCall->setArg(i+1, Arg.take()); |
| } |
| |
| ASTContext& Context = this->getASTContext(); |
| |
| // Create a new DeclRefExpr to refer to the new decl. |
| DeclRefExpr* NewDRE = DeclRefExpr::Create( |
| Context, |
| DRE->getQualifierLoc(), |
| SourceLocation(), |
| NewBuiltinDecl, |
| /*enclosing*/ false, |
| DRE->getLocation(), |
| Context.BuiltinFnTy, |
| DRE->getValueKind()); |
| |
| // Set the callee in the CallExpr. |
| // FIXME: This loses syntactic information. |
| QualType CalleePtrTy = Context.getPointerType(NewBuiltinDecl->getType()); |
| ExprResult PromotedCall = ImpCastExprToType(NewDRE, CalleePtrTy, |
| CK_BuiltinFnToFnPtr); |
| TheCall->setCallee(PromotedCall.take()); |
| |
| // Change the result type of the call to match the original value type. This |
| // is arbitrary, but the codegen for these builtins ins design to handle it |
| // gracefully. |
| TheCall->setType(ResultType); |
| |
| return TheCallResult; |
| } |
| |
| /// CheckObjCString - Checks that the argument to the builtin |
| /// CFString constructor is correct |
| /// Note: It might also make sense to do the UTF-16 conversion here (would |
| /// simplify the backend). |
| bool Sema::CheckObjCString(Expr *Arg) { |
| Arg = Arg->IgnoreParenCasts(); |
| StringLiteral *Literal = dyn_cast<StringLiteral>(Arg); |
| |
| if (!Literal || !Literal->isAscii()) { |
| Diag(Arg->getLocStart(), diag::err_cfstring_literal_not_string_constant) |
| << Arg->getSourceRange(); |
| return true; |
| } |
| |
| if (Literal->containsNonAsciiOrNull()) { |
| StringRef String = Literal->getString(); |
| unsigned NumBytes = String.size(); |
| SmallVector<UTF16, 128> ToBuf(NumBytes); |
| const UTF8 *FromPtr = (UTF8 *)String.data(); |
| UTF16 *ToPtr = &ToBuf[0]; |
| |
| ConversionResult Result = ConvertUTF8toUTF16(&FromPtr, FromPtr + NumBytes, |
| &ToPtr, ToPtr + NumBytes, |
| strictConversion); |
| // Check for conversion failure. |
| if (Result != conversionOK) |
| Diag(Arg->getLocStart(), |
| diag::warn_cfstring_truncated) << Arg->getSourceRange(); |
| } |
| return false; |
| } |
| |
| /// SemaBuiltinVAStart - Check the arguments to __builtin_va_start for validity. |
| /// Emit an error and return true on failure, return false on success. |
| bool Sema::SemaBuiltinVAStart(CallExpr *TheCall) { |
| Expr *Fn = TheCall->getCallee(); |
| if (TheCall->getNumArgs() > 2) { |
| Diag(TheCall->getArg(2)->getLocStart(), |
| diag::err_typecheck_call_too_many_args) |
| << 0 /*function call*/ << 2 << TheCall->getNumArgs() |
| << Fn->getSourceRange() |
| << SourceRange(TheCall->getArg(2)->getLocStart(), |
| (*(TheCall->arg_end()-1))->getLocEnd()); |
| return true; |
| } |
| |
| if (TheCall->getNumArgs() < 2) { |
| return Diag(TheCall->getLocEnd(), |
| diag::err_typecheck_call_too_few_args_at_least) |
| << 0 /*function call*/ << 2 << TheCall->getNumArgs(); |
| } |
| |
| // Type-check the first argument normally. |
| if (checkBuiltinArgument(*this, TheCall, 0)) |
| return true; |
| |
| // Determine whether the current function is variadic or not. |
| BlockScopeInfo *CurBlock = getCurBlock(); |
| bool isVariadic; |
| if (CurBlock) |
| isVariadic = CurBlock->TheDecl->isVariadic(); |
| else if (FunctionDecl *FD = getCurFunctionDecl()) |
| isVariadic = FD->isVariadic(); |
| else |
| isVariadic = getCurMethodDecl()->isVariadic(); |
| |
| if (!isVariadic) { |
| Diag(Fn->getLocStart(), diag::err_va_start_used_in_non_variadic_function); |
| return true; |
| } |
| |
| // Verify that the second argument to the builtin is the last argument of the |
| // current function or method. |
| bool SecondArgIsLastNamedArgument = false; |
| const Expr *Arg = TheCall->getArg(1)->IgnoreParenCasts(); |
| |
| if (const DeclRefExpr *DR = dyn_cast<DeclRefExpr>(Arg)) { |
| if (const ParmVarDecl *PV = dyn_cast<ParmVarDecl>(DR->getDecl())) { |
| // FIXME: This isn't correct for methods (results in bogus warning). |
| // Get the last formal in the current function. |
| const ParmVarDecl *LastArg; |
| if (CurBlock) |
| LastArg = *(CurBlock->TheDecl->param_end()-1); |
| else if (FunctionDecl *FD = getCurFunctionDecl()) |
| LastArg = *(FD->param_end()-1); |
| else |
| LastArg = *(getCurMethodDecl()->param_end()-1); |
| SecondArgIsLastNamedArgument = PV == LastArg; |
| } |
| } |
| |
| if (!SecondArgIsLastNamedArgument) |
| Diag(TheCall->getArg(1)->getLocStart(), |
| diag::warn_second_parameter_of_va_start_not_last_named_argument); |
| return false; |
| } |
| |
| /// SemaBuiltinUnorderedCompare - Handle functions like __builtin_isgreater and |
| /// friends. This is declared to take (...), so we have to check everything. |
| bool Sema::SemaBuiltinUnorderedCompare(CallExpr *TheCall) { |
| if (TheCall->getNumArgs() < 2) |
| return Diag(TheCall->getLocEnd(), diag::err_typecheck_call_too_few_args) |
| << 0 << 2 << TheCall->getNumArgs()/*function call*/; |
| if (TheCall->getNumArgs() > 2) |
| return Diag(TheCall->getArg(2)->getLocStart(), |
| diag::err_typecheck_call_too_many_args) |
| << 0 /*function call*/ << 2 << TheCall->getNumArgs() |
| << SourceRange(TheCall->getArg(2)->getLocStart(), |
| (*(TheCall->arg_end()-1))->getLocEnd()); |
| |
| ExprResult OrigArg0 = TheCall->getArg(0); |
| ExprResult OrigArg1 = TheCall->getArg(1); |
| |
| // Do standard promotions between the two arguments, returning their common |
| // type. |
| QualType Res = UsualArithmeticConversions(OrigArg0, OrigArg1, false); |
| if (OrigArg0.isInvalid() || OrigArg1.isInvalid()) |
| return true; |
| |
| // Make sure any conversions are pushed back into the call; this is |
| // type safe since unordered compare builtins are declared as "_Bool |
| // foo(...)". |
| TheCall->setArg(0, OrigArg0.get()); |
| TheCall->setArg(1, OrigArg1.get()); |
| |
| if (OrigArg0.get()->isTypeDependent() || OrigArg1.get()->isTypeDependent()) |
| return false; |
| |
| // If the common type isn't a real floating type, then the arguments were |
| // invalid for this operation. |
| if (Res.isNull() || !Res->isRealFloatingType()) |
| return Diag(OrigArg0.get()->getLocStart(), |
| diag::err_typecheck_call_invalid_ordered_compare) |
| << OrigArg0.get()->getType() << OrigArg1.get()->getType() |
| << SourceRange(OrigArg0.get()->getLocStart(), OrigArg1.get()->getLocEnd()); |
| |
| return false; |
| } |
| |
| /// SemaBuiltinSemaBuiltinFPClassification - Handle functions like |
| /// __builtin_isnan and friends. This is declared to take (...), so we have |
| /// to check everything. We expect the last argument to be a floating point |
| /// value. |
| bool Sema::SemaBuiltinFPClassification(CallExpr *TheCall, unsigned NumArgs) { |
| if (TheCall->getNumArgs() < NumArgs) |
| return Diag(TheCall->getLocEnd(), diag::err_typecheck_call_too_few_args) |
| << 0 << NumArgs << TheCall->getNumArgs()/*function call*/; |
| if (TheCall->getNumArgs() > NumArgs) |
| return Diag(TheCall->getArg(NumArgs)->getLocStart(), |
| diag::err_typecheck_call_too_many_args) |
| << 0 /*function call*/ << NumArgs << TheCall->getNumArgs() |
| << SourceRange(TheCall->getArg(NumArgs)->getLocStart(), |
| (*(TheCall->arg_end()-1))->getLocEnd()); |
| |
| Expr *OrigArg = TheCall->getArg(NumArgs-1); |
| |
| if (OrigArg->isTypeDependent()) |
| return false; |
| |
| // This operation requires a non-_Complex floating-point number. |
| if (!OrigArg->getType()->isRealFloatingType()) |
| return Diag(OrigArg->getLocStart(), |
| diag::err_typecheck_call_invalid_unary_fp) |
| << OrigArg->getType() << OrigArg->getSourceRange(); |
| |
| // If this is an implicit conversion from float -> double, remove it. |
| if (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(OrigArg)) { |
| Expr *CastArg = Cast->getSubExpr(); |
| if (CastArg->getType()->isSpecificBuiltinType(BuiltinType::Float)) { |
| assert(Cast->getType()->isSpecificBuiltinType(BuiltinType::Double) && |
| "promotion from float to double is the only expected cast here"); |
| Cast->setSubExpr(0); |
| TheCall->setArg(NumArgs-1, CastArg); |
| } |
| } |
| |
| return false; |
| } |
| |
| /// SemaBuiltinShuffleVector - Handle __builtin_shufflevector. |
| // This is declared to take (...), so we have to check everything. |
| ExprResult Sema::SemaBuiltinShuffleVector(CallExpr *TheCall) { |
| if (TheCall->getNumArgs() < 2) |
| return ExprError(Diag(TheCall->getLocEnd(), |
| diag::err_typecheck_call_too_few_args_at_least) |
| << 0 /*function call*/ << 2 << TheCall->getNumArgs() |
| << TheCall->getSourceRange()); |
| |
| // Determine which of the following types of shufflevector we're checking: |
| // 1) unary, vector mask: (lhs, mask) |
| // 2) binary, vector mask: (lhs, rhs, mask) |
| // 3) binary, scalar mask: (lhs, rhs, index, ..., index) |
| QualType resType = TheCall->getArg(0)->getType(); |
| unsigned numElements = 0; |
| |
| if (!TheCall->getArg(0)->isTypeDependent() && |
| !TheCall->getArg(1)->isTypeDependent()) { |
| QualType LHSType = TheCall->getArg(0)->getType(); |
| QualType RHSType = TheCall->getArg(1)->getType(); |
| |
| if (!LHSType->isVectorType() || !RHSType->isVectorType()) { |
| Diag(TheCall->getLocStart(), diag::err_shufflevector_non_vector) |
| << SourceRange(TheCall->getArg(0)->getLocStart(), |
| TheCall->getArg(1)->getLocEnd()); |
| return ExprError(); |
| } |
| |
| numElements = LHSType->getAs<VectorType>()->getNumElements(); |
| unsigned numResElements = TheCall->getNumArgs() - 2; |
| |
| // Check to see if we have a call with 2 vector arguments, the unary shuffle |
| // with mask. If so, verify that RHS is an integer vector type with the |
| // same number of elts as lhs. |
| if (TheCall->getNumArgs() == 2) { |
| if (!RHSType->hasIntegerRepresentation() || |
| RHSType->getAs<VectorType>()->getNumElements() != numElements) |
| Diag(TheCall->getLocStart(), diag::err_shufflevector_incompatible_vector) |
| << SourceRange(TheCall->getArg(1)->getLocStart(), |
| TheCall->getArg(1)->getLocEnd()); |
| numResElements = numElements; |
| } |
| else if (!Context.hasSameUnqualifiedType(LHSType, RHSType)) { |
| Diag(TheCall->getLocStart(), diag::err_shufflevector_incompatible_vector) |
| << SourceRange(TheCall->getArg(0)->getLocStart(), |
| TheCall->getArg(1)->getLocEnd()); |
| return ExprError(); |
| } else if (numElements != numResElements) { |
| QualType eltType = LHSType->getAs<VectorType>()->getElementType(); |
| resType = Context.getVectorType(eltType, numResElements, |
| VectorType::GenericVector); |
| } |
| } |
| |
| for (unsigned i = 2; i < TheCall->getNumArgs(); i++) { |
| if (TheCall->getArg(i)->isTypeDependent() || |
| TheCall->getArg(i)->isValueDependent()) |
| continue; |
| |
| llvm::APSInt Result(32); |
| if (!TheCall->getArg(i)->isIntegerConstantExpr(Result, Context)) |
| return ExprError(Diag(TheCall->getLocStart(), |
| diag::err_shufflevector_nonconstant_argument) |
| << TheCall->getArg(i)->getSourceRange()); |
| |
| if (Result.getActiveBits() > 64 || Result.getZExtValue() >= numElements*2) |
| return ExprError(Diag(TheCall->getLocStart(), |
| diag::err_shufflevector_argument_too_large) |
| << TheCall->getArg(i)->getSourceRange()); |
| } |
| |
| SmallVector<Expr*, 32> exprs; |
| |
| for (unsigned i = 0, e = TheCall->getNumArgs(); i != e; i++) { |
| exprs.push_back(TheCall->getArg(i)); |
| TheCall->setArg(i, 0); |
| } |
| |
| return Owned(new (Context) ShuffleVectorExpr(Context, exprs, resType, |
| TheCall->getCallee()->getLocStart(), |
| TheCall->getRParenLoc())); |
| } |
| |
| /// SemaBuiltinPrefetch - Handle __builtin_prefetch. |
| // This is declared to take (const void*, ...) and can take two |
| // optional constant int args. |
| bool Sema::SemaBuiltinPrefetch(CallExpr *TheCall) { |
| unsigned NumArgs = TheCall->getNumArgs(); |
| |
| if (NumArgs > 3) |
| return Diag(TheCall->getLocEnd(), |
| diag::err_typecheck_call_too_many_args_at_most) |
| << 0 /*function call*/ << 3 << NumArgs |
| << TheCall->getSourceRange(); |
| |
| // Argument 0 is checked for us and the remaining arguments must be |
| // constant integers. |
| for (unsigned i = 1; i != NumArgs; ++i) { |
| Expr *Arg = TheCall->getArg(i); |
| |
| // We can't check the value of a dependent argument. |
| if (Arg->isTypeDependent() || Arg->isValueDependent()) |
| continue; |
| |
| llvm::APSInt Result; |
| if (SemaBuiltinConstantArg(TheCall, i, Result)) |
| return true; |
| |
| // FIXME: gcc issues a warning and rewrites these to 0. These |
| // seems especially odd for the third argument since the default |
| // is 3. |
| if (i == 1) { |
| if (Result.getLimitedValue() > 1) |
| return Diag(TheCall->getLocStart(), diag::err_argument_invalid_range) |
| << "0" << "1" << Arg->getSourceRange(); |
| } else { |
| if (Result.getLimitedValue() > 3) |
| return Diag(TheCall->getLocStart(), diag::err_argument_invalid_range) |
| << "0" << "3" << Arg->getSourceRange(); |
| } |
| } |
| |
| return false; |
| } |
| |
| /// SemaBuiltinConstantArg - Handle a check if argument ArgNum of CallExpr |
| /// TheCall is a constant expression. |
| bool Sema::SemaBuiltinConstantArg(CallExpr *TheCall, int ArgNum, |
| llvm::APSInt &Result) { |
| Expr *Arg = TheCall->getArg(ArgNum); |
| DeclRefExpr *DRE =cast<DeclRefExpr>(TheCall->getCallee()->IgnoreParenCasts()); |
| FunctionDecl *FDecl = cast<FunctionDecl>(DRE->getDecl()); |
| |
| if (Arg->isTypeDependent() || Arg->isValueDependent()) return false; |
| |
| if (!Arg->isIntegerConstantExpr(Result, Context)) |
| return Diag(TheCall->getLocStart(), diag::err_constant_integer_arg_type) |
| << FDecl->getDeclName() << Arg->getSourceRange(); |
| |
| return false; |
| } |
| |
| /// SemaBuiltinObjectSize - Handle __builtin_object_size(void *ptr, |
| /// int type). This simply type checks that type is one of the defined |
| /// constants (0-3). |
| // For compatibility check 0-3, llvm only handles 0 and 2. |
| bool Sema::SemaBuiltinObjectSize(CallExpr *TheCall) { |
| llvm::APSInt Result; |
| |
| // We can't check the value of a dependent argument. |
| if (TheCall->getArg(1)->isTypeDependent() || |
| TheCall->getArg(1)->isValueDependent()) |
| return false; |
| |
| // Check constant-ness first. |
| if (SemaBuiltinConstantArg(TheCall, 1, Result)) |
| return true; |
| |
| Expr *Arg = TheCall->getArg(1); |
| if (Result.getSExtValue() < 0 || Result.getSExtValue() > 3) { |
| return Diag(TheCall->getLocStart(), diag::err_argument_invalid_range) |
| << "0" << "3" << SourceRange(Arg->getLocStart(), Arg->getLocEnd()); |
| } |
| |
| return false; |
| } |
| |
| /// SemaBuiltinLongjmp - Handle __builtin_longjmp(void *env[5], int val). |
| /// This checks that val is a constant 1. |
| bool Sema::SemaBuiltinLongjmp(CallExpr *TheCall) { |
| Expr *Arg = TheCall->getArg(1); |
| llvm::APSInt Result; |
| |
| // TODO: This is less than ideal. Overload this to take a value. |
| if (SemaBuiltinConstantArg(TheCall, 1, Result)) |
| return true; |
| |
| if (Result != 1) |
| return Diag(TheCall->getLocStart(), diag::err_builtin_longjmp_invalid_val) |
| << SourceRange(Arg->getLocStart(), Arg->getLocEnd()); |
| |
| return false; |
| } |
| |
| // Determine if an expression is a string literal or constant string. |
| // If this function returns false on the arguments to a function expecting a |
| // format string, we will usually need to emit a warning. |
| // True string literals are then checked by CheckFormatString. |
| Sema::StringLiteralCheckType |
| Sema::checkFormatStringExpr(const Expr *E, Expr **Args, |
| unsigned NumArgs, bool HasVAListArg, |
| unsigned format_idx, unsigned firstDataArg, |
| FormatStringType Type, VariadicCallType CallType, |
| bool inFunctionCall) { |
| tryAgain: |
| if (E->isTypeDependent() || E->isValueDependent()) |
| return SLCT_NotALiteral; |
| |
| E = E->IgnoreParenCasts(); |
| |
| if (E->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull)) |
| // Technically -Wformat-nonliteral does not warn about this case. |
| // The behavior of printf and friends in this case is implementation |
| // dependent. Ideally if the format string cannot be null then |
| // it should have a 'nonnull' attribute in the function prototype. |
| return SLCT_CheckedLiteral; |
| |
| switch (E->getStmtClass()) { |
| case Stmt::BinaryConditionalOperatorClass: |
| case Stmt::ConditionalOperatorClass: { |
| // The expression is a literal if both sub-expressions were, and it was |
| // completely checked only if both sub-expressions were checked. |
| const AbstractConditionalOperator *C = |
| cast<AbstractConditionalOperator>(E); |
| StringLiteralCheckType Left = |
| checkFormatStringExpr(C->getTrueExpr(), Args, NumArgs, |
| HasVAListArg, format_idx, firstDataArg, |
| Type, CallType, inFunctionCall); |
| if (Left == SLCT_NotALiteral) |
| return SLCT_NotALiteral; |
| StringLiteralCheckType Right = |
| checkFormatStringExpr(C->getFalseExpr(), Args, NumArgs, |
| HasVAListArg, format_idx, firstDataArg, |
| Type, CallType, inFunctionCall); |
| return Left < Right ? Left : Right; |
| } |
| |
| case Stmt::ImplicitCastExprClass: { |
| E = cast<ImplicitCastExpr>(E)->getSubExpr(); |
| goto tryAgain; |
| } |
| |
| case Stmt::OpaqueValueExprClass: |
| if (const Expr *src = cast<OpaqueValueExpr>(E)->getSourceExpr()) { |
| E = src; |
| goto tryAgain; |
| } |
| return SLCT_NotALiteral; |
| |
| case Stmt::PredefinedExprClass: |
| // While __func__, etc., are technically not string literals, they |
| // cannot contain format specifiers and thus are not a security |
| // liability. |
| return SLCT_UncheckedLiteral; |
| |
| case Stmt::DeclRefExprClass: { |
| const DeclRefExpr *DR = cast<DeclRefExpr>(E); |
| |
| // As an exception, do not flag errors for variables binding to |
| // const string literals. |
| if (const VarDecl *VD = dyn_cast<VarDecl>(DR->getDecl())) { |
| bool isConstant = false; |
| QualType T = DR->getType(); |
| |
| if (const ArrayType *AT = Context.getAsArrayType(T)) { |
| isConstant = AT->getElementType().isConstant(Context); |
| } else if (const PointerType *PT = T->getAs<PointerType>()) { |
| isConstant = T.isConstant(Context) && |
| PT->getPointeeType().isConstant(Context); |
| } else if (T->isObjCObjectPointerType()) { |
| // In ObjC, there is usually no "const ObjectPointer" type, |
| // so don't check if the pointee type is constant. |
| isConstant = T.isConstant(Context); |
| } |
| |
| if (isConstant) { |
| if (const Expr *Init = VD->getAnyInitializer()) { |
| // Look through initializers like const char c[] = { "foo" } |
| if (const InitListExpr *InitList = dyn_cast<InitListExpr>(Init)) { |
| if (InitList->isStringLiteralInit()) |
| Init = InitList->getInit(0)->IgnoreParenImpCasts(); |
| } |
| return checkFormatStringExpr(Init, Args, NumArgs, |
| HasVAListArg, format_idx, |
| firstDataArg, Type, CallType, |
| /*inFunctionCall*/false); |
| } |
| } |
| |
| // For vprintf* functions (i.e., HasVAListArg==true), we add a |
| // special check to see if the format string is a function parameter |
| // of the function calling the printf function. If the function |
| // has an attribute indicating it is a printf-like function, then we |
| // should suppress warnings concerning non-literals being used in a call |
| // to a vprintf function. For example: |
| // |
| // void |
| // logmessage(char const *fmt __attribute__ (format (printf, 1, 2)), ...){ |
| // va_list ap; |
| // va_start(ap, fmt); |
| // vprintf(fmt, ap); // Do NOT emit a warning about "fmt". |
| // ... |
| // |
| if (HasVAListArg) { |
| if (const ParmVarDecl *PV = dyn_cast<ParmVarDecl>(VD)) { |
| if (const NamedDecl *ND = dyn_cast<NamedDecl>(PV->getDeclContext())) { |
| int PVIndex = PV->getFunctionScopeIndex() + 1; |
| for (specific_attr_iterator<FormatAttr> |
| i = ND->specific_attr_begin<FormatAttr>(), |
| e = ND->specific_attr_end<FormatAttr>(); i != e ; ++i) { |
| FormatAttr *PVFormat = *i; |
| // adjust for implicit parameter |
| if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(ND)) |
| if (MD->isInstance()) |
| ++PVIndex; |
| // We also check if the formats are compatible. |
| // We can't pass a 'scanf' string to a 'printf' function. |
| if (PVIndex == PVFormat->getFormatIdx() && |
| Type == GetFormatStringType(PVFormat)) |
| return SLCT_UncheckedLiteral; |
| } |
| } |
| } |
| } |
| } |
| |
| return SLCT_NotALiteral; |
| } |
| |
| case Stmt::CallExprClass: |
| case Stmt::CXXMemberCallExprClass: { |
| const CallExpr *CE = cast<CallExpr>(E); |
| if (const NamedDecl *ND = dyn_cast_or_null<NamedDecl>(CE->getCalleeDecl())) { |
| if (const FormatArgAttr *FA = ND->getAttr<FormatArgAttr>()) { |
| unsigned ArgIndex = FA->getFormatIdx(); |
| if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(ND)) |
| if (MD->isInstance()) |
| --ArgIndex; |
| const Expr *Arg = CE->getArg(ArgIndex - 1); |
| |
| return checkFormatStringExpr(Arg, Args, NumArgs, |
| HasVAListArg, format_idx, firstDataArg, |
| Type, CallType, inFunctionCall); |
| } else if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(ND)) { |
| unsigned BuiltinID = FD->getBuiltinID(); |
| if (BuiltinID == Builtin::BI__builtin___CFStringMakeConstantString || |
| BuiltinID == Builtin::BI__builtin___NSStringMakeConstantString) { |
| const Expr *Arg = CE->getArg(0); |
| return checkFormatStringExpr(Arg, Args, NumArgs, |
| HasVAListArg, format_idx, |
| firstDataArg, Type, CallType, |
| inFunctionCall); |
| } |
| } |
| } |
| |
| return SLCT_NotALiteral; |
| } |
| case Stmt::ObjCStringLiteralClass: |
| case Stmt::StringLiteralClass: { |
| const StringLiteral *StrE = NULL; |
| |
| if (const ObjCStringLiteral *ObjCFExpr = dyn_cast<ObjCStringLiteral>(E)) |
| StrE = ObjCFExpr->getString(); |
| else |
| StrE = cast<StringLiteral>(E); |
| |
| if (StrE) { |
| CheckFormatString(StrE, E, Args, NumArgs, HasVAListArg, format_idx, |
| firstDataArg, Type, inFunctionCall, CallType); |
| return SLCT_CheckedLiteral; |
| } |
| |
| return SLCT_NotALiteral; |
| } |
| |
| default: |
| return SLCT_NotALiteral; |
| } |
| } |
| |
| void |
| Sema::CheckNonNullArguments(const NonNullAttr *NonNull, |
| const Expr * const *ExprArgs, |
| SourceLocation CallSiteLoc) { |
| for (NonNullAttr::args_iterator i = NonNull->args_begin(), |
| e = NonNull->args_end(); |
| i != e; ++i) { |
| const Expr *ArgExpr = ExprArgs[*i]; |
| if (ArgExpr->isNullPointerConstant(Context, |
| Expr::NPC_ValueDependentIsNotNull)) |
| Diag(CallSiteLoc, diag::warn_null_arg) << ArgExpr->getSourceRange(); |
| } |
| } |
| |
| Sema::FormatStringType Sema::GetFormatStringType(const FormatAttr *Format) { |
| return llvm::StringSwitch<FormatStringType>(Format->getType()) |
| .Case("scanf", FST_Scanf) |
| .Cases("printf", "printf0", FST_Printf) |
| .Cases("NSString", "CFString", FST_NSString) |
| .Case("strftime", FST_Strftime) |
| .Case("strfmon", FST_Strfmon) |
| .Cases("kprintf", "cmn_err", "vcmn_err", "zcmn_err", FST_Kprintf) |
| .Default(FST_Unknown); |
| } |
| |
| /// CheckFormatArguments - Check calls to printf and scanf (and similar |
| /// functions) for correct use of format strings. |
| /// Returns true if a format string has been fully checked. |
| bool Sema::CheckFormatArguments(const FormatAttr *Format, Expr **Args, |
| unsigned NumArgs, bool IsCXXMember, |
| VariadicCallType CallType, |
| SourceLocation Loc, SourceRange Range) { |
| FormatStringInfo FSI; |
| if (getFormatStringInfo(Format, IsCXXMember, &FSI)) |
| return CheckFormatArguments(Args, NumArgs, FSI.HasVAListArg, FSI.FormatIdx, |
| FSI.FirstDataArg, GetFormatStringType(Format), |
| CallType, Loc, Range); |
| return false; |
| } |
| |
| bool Sema::CheckFormatArguments(Expr **Args, unsigned NumArgs, |
| bool HasVAListArg, unsigned format_idx, |
| unsigned firstDataArg, FormatStringType Type, |
| VariadicCallType CallType, |
| SourceLocation Loc, SourceRange Range) { |
| // CHECK: printf/scanf-like function is called with no format string. |
| if (format_idx >= NumArgs) { |
| Diag(Loc, diag::warn_missing_format_string) << Range; |
| return false; |
| } |
| |
| const Expr *OrigFormatExpr = Args[format_idx]->IgnoreParenCasts(); |
| |
| // CHECK: format string is not a string literal. |
| // |
| // Dynamically generated format strings are difficult to |
| // automatically vet at compile time. Requiring that format strings |
| // are string literals: (1) permits the checking of format strings by |
| // the compiler and thereby (2) can practically remove the source of |
| // many format string exploits. |
| |
| // Format string can be either ObjC string (e.g. @"%d") or |
| // C string (e.g. "%d") |
| // ObjC string uses the same format specifiers as C string, so we can use |
| // the same format string checking logic for both ObjC and C strings. |
| StringLiteralCheckType CT = |
| checkFormatStringExpr(OrigFormatExpr, Args, NumArgs, HasVAListArg, |
| format_idx, firstDataArg, Type, CallType); |
| if (CT != SLCT_NotALiteral) |
| // Literal format string found, check done! |
| return CT == SLCT_CheckedLiteral; |
| |
| // Strftime is particular as it always uses a single 'time' argument, |
| // so it is safe to pass a non-literal string. |
| if (Type == FST_Strftime) |
| return false; |
| |
| // Do not emit diag when the string param is a macro expansion and the |
| // format is either NSString or CFString. This is a hack to prevent |
| // diag when using the NSLocalizedString and CFCopyLocalizedString macros |
| // which are usually used in place of NS and CF string literals. |
| if (Type == FST_NSString && |
| SourceMgr.isInSystemMacro(Args[format_idx]->getLocStart())) |
| return false; |
| |
| // If there are no arguments specified, warn with -Wformat-security, otherwise |
| // warn only with -Wformat-nonliteral. |
| if (NumArgs == format_idx+1) |
| Diag(Args[format_idx]->getLocStart(), |
| diag::warn_format_nonliteral_noargs) |
| << OrigFormatExpr->getSourceRange(); |
| else |
| Diag(Args[format_idx]->getLocStart(), |
| diag::warn_format_nonliteral) |
| << OrigFormatExpr->getSourceRange(); |
| return false; |
| } |
| |
| namespace { |
| class CheckFormatHandler : public analyze_format_string::FormatStringHandler { |
| protected: |
| Sema &S; |
| const StringLiteral *FExpr; |
| const Expr *OrigFormatExpr; |
| const unsigned FirstDataArg; |
| const unsigned NumDataArgs; |
| const char *Beg; // Start of format string. |
| const bool HasVAListArg; |
| const Expr * const *Args; |
| const unsigned NumArgs; |
| unsigned FormatIdx; |
| llvm::BitVector CoveredArgs; |
| bool usesPositionalArgs; |
| bool atFirstArg; |
| bool inFunctionCall; |
| Sema::VariadicCallType CallType; |
| public: |
| CheckFormatHandler(Sema &s, const StringLiteral *fexpr, |
| const Expr *origFormatExpr, unsigned firstDataArg, |
| unsigned numDataArgs, const char *beg, bool hasVAListArg, |
| Expr **args, unsigned numArgs, |
| unsigned formatIdx, bool inFunctionCall, |
| Sema::VariadicCallType callType) |
| : S(s), FExpr(fexpr), OrigFormatExpr(origFormatExpr), |
| FirstDataArg(firstDataArg), NumDataArgs(numDataArgs), |
| Beg(beg), HasVAListArg(hasVAListArg), |
| Args(args), NumArgs(numArgs), FormatIdx(formatIdx), |
| usesPositionalArgs(false), atFirstArg(true), |
| inFunctionCall(inFunctionCall), CallType(callType) { |
| CoveredArgs.resize(numDataArgs); |
| CoveredArgs.reset(); |
| } |
| |
| void DoneProcessing(); |
| |
| void HandleIncompleteSpecifier(const char *startSpecifier, |
| unsigned specifierLen); |
| |
| void HandleNonStandardLengthModifier( |
| const analyze_format_string::LengthModifier &LM, |
| const char *startSpecifier, unsigned specifierLen); |
| |
| void HandleNonStandardConversionSpecifier( |
| const analyze_format_string::ConversionSpecifier &CS, |
| const char *startSpecifier, unsigned specifierLen); |
| |
| void HandleNonStandardConversionSpecification( |
| const analyze_format_string::LengthModifier &LM, |
| const analyze_format_string::ConversionSpecifier &CS, |
| const char *startSpecifier, unsigned specifierLen); |
| |
| virtual void HandlePosition(const char *startPos, unsigned posLen); |
| |
| virtual void HandleInvalidPosition(const char *startSpecifier, |
| unsigned specifierLen, |
| analyze_format_string::PositionContext p); |
| |
| virtual void HandleZeroPosition(const char *startPos, unsigned posLen); |
| |
| void HandleNullChar(const char *nullCharacter); |
| |
| template <typename Range> |
| static void EmitFormatDiagnostic(Sema &S, bool inFunctionCall, |
| const Expr *ArgumentExpr, |
| PartialDiagnostic PDiag, |
| SourceLocation StringLoc, |
| bool IsStringLocation, Range StringRange, |
| FixItHint Fixit = FixItHint()); |
| |
| protected: |
| bool HandleInvalidConversionSpecifier(unsigned argIndex, SourceLocation Loc, |
| const char *startSpec, |
| unsigned specifierLen, |
| const char *csStart, unsigned csLen); |
| |
| void HandlePositionalNonpositionalArgs(SourceLocation Loc, |
| const char *startSpec, |
| unsigned specifierLen); |
| |
| SourceRange getFormatStringRange(); |
| CharSourceRange getSpecifierRange(const char *startSpecifier, |
| unsigned specifierLen); |
| SourceLocation getLocationOfByte(const char *x); |
| |
| const Expr *getDataArg(unsigned i) const; |
| |
| bool CheckNumArgs(const analyze_format_string::FormatSpecifier &FS, |
| const analyze_format_string::ConversionSpecifier &CS, |
| const char *startSpecifier, unsigned specifierLen, |
| unsigned argIndex); |
| |
| template <typename Range> |
| void EmitFormatDiagnostic(PartialDiagnostic PDiag, SourceLocation StringLoc, |
| bool IsStringLocation, Range StringRange, |
| FixItHint Fixit = FixItHint()); |
| |
| void CheckPositionalAndNonpositionalArgs( |
| const analyze_format_string::FormatSpecifier *FS); |
| }; |
| } |
| |
| SourceRange CheckFormatHandler::getFormatStringRange() { |
| return OrigFormatExpr->getSourceRange(); |
| } |
| |
| CharSourceRange CheckFormatHandler:: |
| getSpecifierRange(const char *startSpecifier, unsigned specifierLen) { |
| SourceLocation Start = getLocationOfByte(startSpecifier); |
| SourceLocation End = getLocationOfByte(startSpecifier + specifierLen - 1); |
| |
| // Advance the end SourceLocation by one due to half-open ranges. |
| End = End.getLocWithOffset(1); |
| |
| return CharSourceRange::getCharRange(Start, End); |
| } |
| |
| SourceLocation CheckFormatHandler::getLocationOfByte(const char *x) { |
| return S.getLocationOfStringLiteralByte(FExpr, x - Beg); |
| } |
| |
| void CheckFormatHandler::HandleIncompleteSpecifier(const char *startSpecifier, |
| unsigned specifierLen){ |
| EmitFormatDiagnostic(S.PDiag(diag::warn_printf_incomplete_specifier), |
| getLocationOfByte(startSpecifier), |
| /*IsStringLocation*/true, |
| getSpecifierRange(startSpecifier, specifierLen)); |
| } |
| |
| void CheckFormatHandler::HandleNonStandardLengthModifier( |
| const analyze_format_string::LengthModifier &LM, |
| const char *startSpecifier, unsigned specifierLen) { |
| EmitFormatDiagnostic(S.PDiag(diag::warn_format_non_standard) << LM.toString() |
| << 0, |
| getLocationOfByte(LM.getStart()), |
| /*IsStringLocation*/true, |
| getSpecifierRange(startSpecifier, specifierLen)); |
| } |
| |
| void CheckFormatHandler::HandleNonStandardConversionSpecifier( |
| const analyze_format_string::ConversionSpecifier &CS, |
| const char *startSpecifier, unsigned specifierLen) { |
| EmitFormatDiagnostic(S.PDiag(diag::warn_format_non_standard) << CS.toString() |
| << 1, |
| getLocationOfByte(CS.getStart()), |
| /*IsStringLocation*/true, |
| getSpecifierRange(startSpecifier, specifierLen)); |
| } |
| |
| void CheckFormatHandler::HandleNonStandardConversionSpecification( |
| const analyze_format_string::LengthModifier &LM, |
| const analyze_format_string::ConversionSpecifier &CS, |
| const char *startSpecifier, unsigned specifierLen) { |
| EmitFormatDiagnostic(S.PDiag(diag::warn_format_non_standard_conversion_spec) |
| << LM.toString() << CS.toString(), |
| getLocationOfByte(LM.getStart()), |
| /*IsStringLocation*/true, |
| getSpecifierRange(startSpecifier, specifierLen)); |
| } |
| |
| void CheckFormatHandler::HandlePosition(const char *startPos, |
| unsigned posLen) { |
| EmitFormatDiagnostic(S.PDiag(diag::warn_format_non_standard_positional_arg), |
| getLocationOfByte(startPos), |
| /*IsStringLocation*/true, |
| getSpecifierRange(startPos, posLen)); |
| } |
| |
| void |
| CheckFormatHandler::HandleInvalidPosition(const char *startPos, unsigned posLen, |
| analyze_format_string::PositionContext p) { |
| EmitFormatDiagnostic(S.PDiag(diag::warn_format_invalid_positional_specifier) |
| << (unsigned) p, |
| getLocationOfByte(startPos), /*IsStringLocation*/true, |
| getSpecifierRange(startPos, posLen)); |
| } |
| |
| void CheckFormatHandler::HandleZeroPosition(const char *startPos, |
| unsigned posLen) { |
| EmitFormatDiagnostic(S.PDiag(diag::warn_format_zero_positional_specifier), |
| getLocationOfByte(startPos), |
| /*IsStringLocation*/true, |
| getSpecifierRange(startPos, posLen)); |
| } |
| |
| void CheckFormatHandler::HandleNullChar(const char *nullCharacter) { |
| if (!isa<ObjCStringLiteral>(OrigFormatExpr)) { |
| // The presence of a null character is likely an error. |
| EmitFormatDiagnostic( |
| S.PDiag(diag::warn_printf_format_string_contains_null_char), |
| getLocationOfByte(nullCharacter), /*IsStringLocation*/true, |
| getFormatStringRange()); |
| } |
| } |
| |
| // Note that this may return NULL if there was an error parsing or building |
| // one of the argument expressions. |
| const Expr *CheckFormatHandler::getDataArg(unsigned i) const { |
| return Args[FirstDataArg + i]; |
| } |
| |
| void CheckFormatHandler::DoneProcessing() { |
| // Does the number of data arguments exceed the number of |
| // format conversions in the format string? |
| if (!HasVAListArg) { |
| // Find any arguments that weren't covered. |
| CoveredArgs.flip(); |
| signed notCoveredArg = CoveredArgs.find_first(); |
| if (notCoveredArg >= 0) { |
| assert((unsigned)notCoveredArg < NumDataArgs); |
| if (const Expr *E = getDataArg((unsigned) notCoveredArg)) { |
| SourceLocation Loc = E->getLocStart(); |
| if (!S.getSourceManager().isInSystemMacro(Loc)) { |
| EmitFormatDiagnostic(S.PDiag(diag::warn_printf_data_arg_not_used), |
| Loc, /*IsStringLocation*/false, |
| getFormatStringRange()); |
| } |
| } |
| } |
| } |
| } |
| |
| bool |
| CheckFormatHandler::HandleInvalidConversionSpecifier(unsigned argIndex, |
| SourceLocation Loc, |
| const char *startSpec, |
| unsigned specifierLen, |
| const char *csStart, |
| unsigned csLen) { |
| |
| bool keepGoing = true; |
| if (argIndex < NumDataArgs) { |
| // Consider the argument coverered, even though the specifier doesn't |
| // make sense. |
| CoveredArgs.set(argIndex); |
| } |
| else { |
| // If argIndex exceeds the number of data arguments we |
| // don't issue a warning because that is just a cascade of warnings (and |
| // they may have intended '%%' anyway). We don't want to continue processing |
| // the format string after this point, however, as we will like just get |
| // gibberish when trying to match arguments. |
| keepGoing = false; |
| } |
| |
| EmitFormatDiagnostic(S.PDiag(diag::warn_format_invalid_conversion) |
| << StringRef(csStart, csLen), |
| Loc, /*IsStringLocation*/true, |
| getSpecifierRange(startSpec, specifierLen)); |
| |
| return keepGoing; |
| } |
| |
| void |
| CheckFormatHandler::HandlePositionalNonpositionalArgs(SourceLocation Loc, |
| const char *startSpec, |
| unsigned specifierLen) { |
| EmitFormatDiagnostic( |
| S.PDiag(diag::warn_format_mix_positional_nonpositional_args), |
| Loc, /*isStringLoc*/true, getSpecifierRange(startSpec, specifierLen)); |
| } |
| |
| bool |
| CheckFormatHandler::CheckNumArgs( |
| const analyze_format_string::FormatSpecifier &FS, |
| const analyze_format_string::ConversionSpecifier &CS, |
| const char *startSpecifier, unsigned specifierLen, unsigned argIndex) { |
| |
| if (argIndex >= NumDataArgs) { |
| PartialDiagnostic PDiag = FS.usesPositionalArg() |
| ? (S.PDiag(diag::warn_printf_positional_arg_exceeds_data_args) |
| << (argIndex+1) << NumDataArgs) |
| : S.PDiag(diag::warn_printf_insufficient_data_args); |
| EmitFormatDiagnostic( |
| PDiag, getLocationOfByte(CS.getStart()), /*IsStringLocation*/true, |
| getSpecifierRange(startSpecifier, specifierLen)); |
| return false; |
| } |
| return true; |
| } |
| |
| template<typename Range> |
| void CheckFormatHandler::EmitFormatDiagnostic(PartialDiagnostic PDiag, |
| SourceLocation Loc, |
| bool IsStringLocation, |
| Range StringRange, |
| FixItHint FixIt) { |
| EmitFormatDiagnostic(S, inFunctionCall, Args[FormatIdx], PDiag, |
| Loc, IsStringLocation, StringRange, FixIt); |
| } |
| |
| /// \brief If the format string is not within the funcion call, emit a note |
| /// so that the function call and string are in diagnostic messages. |
| /// |
| /// \param InFunctionCall if true, the format string is within the function |
| /// call and only one diagnostic message will be produced. Otherwise, an |
| /// extra note will be emitted pointing to location of the format string. |
| /// |
| /// \param ArgumentExpr the expression that is passed as the format string |
| /// argument in the function call. Used for getting locations when two |
| /// diagnostics are emitted. |
| /// |
| /// \param PDiag the callee should already have provided any strings for the |
| /// diagnostic message. This function only adds locations and fixits |
| /// to diagnostics. |
| /// |
| /// \param Loc primary location for diagnostic. If two diagnostics are |
| /// required, one will be at Loc and a new SourceLocation will be created for |
| /// the other one. |
| /// |
| /// \param IsStringLocation if true, Loc points to the format string should be |
| /// used for the note. Otherwise, Loc points to the argument list and will |
| /// be used with PDiag. |
| /// |
| /// \param StringRange some or all of the string to highlight. This is |
| /// templated so it can accept either a CharSourceRange or a SourceRange. |
| /// |
| /// \param FixIt optional fix it hint for the format string. |
| template<typename Range> |
| void CheckFormatHandler::EmitFormatDiagnostic(Sema &S, bool InFunctionCall, |
| const Expr *ArgumentExpr, |
| PartialDiagnostic PDiag, |
| SourceLocation Loc, |
| bool IsStringLocation, |
| Range StringRange, |
| FixItHint FixIt) { |
| if (InFunctionCall) |
| S.Diag(Loc, PDiag) << StringRange << FixIt; |
| else { |
| S.Diag(IsStringLocation ? ArgumentExpr->getExprLoc() : Loc, PDiag) |
| << ArgumentExpr->getSourceRange(); |
| S.Diag(IsStringLocation ? Loc : StringRange.getBegin(), |
| diag::note_format_string_defined) |
| << StringRange << FixIt; |
| } |
| } |
| |
| //===--- CHECK: Printf format string checking ------------------------------===// |
| |
| namespace { |
| class CheckPrintfHandler : public CheckFormatHandler { |
| bool ObjCContext; |
| public: |
| CheckPrintfHandler(Sema &s, const StringLiteral *fexpr, |
| const Expr *origFormatExpr, unsigned firstDataArg, |
| unsigned numDataArgs, bool isObjC, |
| const char *beg, bool hasVAListArg, |
| Expr **Args, unsigned NumArgs, |
| unsigned formatIdx, bool inFunctionCall, |
| Sema::VariadicCallType CallType) |
| : CheckFormatHandler(s, fexpr, origFormatExpr, firstDataArg, |
| numDataArgs, beg, hasVAListArg, Args, NumArgs, |
| formatIdx, inFunctionCall, CallType), ObjCContext(isObjC) |
| {} |
| |
| |
| bool HandleInvalidPrintfConversionSpecifier( |
| const analyze_printf::PrintfSpecifier &FS, |
| const char *startSpecifier, |
| unsigned specifierLen); |
| |
| bool HandlePrintfSpecifier(const analyze_printf::PrintfSpecifier &FS, |
| const char *startSpecifier, |
| unsigned specifierLen); |
| bool checkFormatExpr(const analyze_printf::PrintfSpecifier &FS, |
| const char *StartSpecifier, |
| unsigned SpecifierLen, |
| const Expr *E); |
| |
| bool HandleAmount(const analyze_format_string::OptionalAmount &Amt, unsigned k, |
| const char *startSpecifier, unsigned specifierLen); |
| void HandleInvalidAmount(const analyze_printf::PrintfSpecifier &FS, |
| const analyze_printf::OptionalAmount &Amt, |
| unsigned type, |
| const char *startSpecifier, unsigned specifierLen); |
| void HandleFlag(const analyze_printf::PrintfSpecifier &FS, |
| const analyze_printf::OptionalFlag &flag, |
| const char *startSpecifier, unsigned specifierLen); |
| void HandleIgnoredFlag(const analyze_printf::PrintfSpecifier &FS, |
| const analyze_printf::OptionalFlag &ignoredFlag, |
| const analyze_printf::OptionalFlag &flag, |
| const char *startSpecifier, unsigned specifierLen); |
| bool checkForCStrMembers(const analyze_printf::ArgType &AT, |
| const Expr *E, const CharSourceRange &CSR); |
| |
| }; |
| } |
| |
| bool CheckPrintfHandler::HandleInvalidPrintfConversionSpecifier( |
| const analyze_printf::PrintfSpecifier &FS, |
| const char *startSpecifier, |
| unsigned specifierLen) { |
| const analyze_printf::PrintfConversionSpecifier &CS = |
| FS.getConversionSpecifier(); |
| |
| return HandleInvalidConversionSpecifier(FS.getArgIndex(), |
| getLocationOfByte(CS.getStart()), |
| startSpecifier, specifierLen, |
| CS.getStart(), CS.getLength()); |
| } |
| |
| bool CheckPrintfHandler::HandleAmount( |
| const analyze_format_string::OptionalAmount &Amt, |
| unsigned k, const char *startSpecifier, |
| unsigned specifierLen) { |
| |
| if (Amt.hasDataArgument()) { |
| if (!HasVAListArg) { |
| unsigned argIndex = Amt.getArgIndex(); |
| if (argIndex >= NumDataArgs) { |
| EmitFormatDiagnostic(S.PDiag(diag::warn_printf_asterisk_missing_arg) |
| << k, |
| getLocationOfByte(Amt.getStart()), |
| /*IsStringLocation*/true, |
| getSpecifierRange(startSpecifier, specifierLen)); |
| // Don't do any more checking. We will just emit |
| // spurious errors. |
| return false; |
| } |
| |
| // Type check the data argument. It should be an 'int'. |
| // Although not in conformance with C99, we also allow the argument to be |
| // an 'unsigned int' as that is a reasonably safe case. GCC also |
| // doesn't emit a warning for that case. |
| CoveredArgs.set(argIndex); |
| const Expr *Arg = getDataArg(argIndex); |
| if (!Arg) |
| return false; |
| |
| QualType T = Arg->getType(); |
| |
| const analyze_printf::ArgType &AT = Amt.getArgType(S.Context); |
| assert(AT.isValid()); |
| |
| if (!AT.matchesType(S.Context, T)) { |
| EmitFormatDiagnostic(S.PDiag(diag::warn_printf_asterisk_wrong_type) |
| << k << AT.getRepresentativeTypeName(S.Context) |
| << T << Arg->getSourceRange(), |
| getLocationOfByte(Amt.getStart()), |
| /*IsStringLocation*/true, |
| getSpecifierRange(startSpecifier, specifierLen)); |
| // Don't do any more checking. We will just emit |
| // spurious errors. |
| return false; |
| } |
| } |
| } |
| return true; |
| } |
| |
| void CheckPrintfHandler::HandleInvalidAmount( |
| const analyze_printf::PrintfSpecifier &FS, |
| const analyze_printf::OptionalAmount &Amt, |
| unsigned type, |
| const char *startSpecifier, |
| unsigned specifierLen) { |
| const analyze_printf::PrintfConversionSpecifier &CS = |
| FS.getConversionSpecifier(); |
| |
| FixItHint fixit = |
| Amt.getHowSpecified() == analyze_printf::OptionalAmount::Constant |
| ? FixItHint::CreateRemoval(getSpecifierRange(Amt.getStart(), |
| Amt.getConstantLength())) |
| : FixItHint(); |
| |
| EmitFormatDiagnostic(S.PDiag(diag::warn_printf_nonsensical_optional_amount) |
| << type << CS.toString(), |
| getLocationOfByte(Amt.getStart()), |
| /*IsStringLocation*/true, |
| getSpecifierRange(startSpecifier, specifierLen), |
| fixit); |
| } |
| |
| void CheckPrintfHandler::HandleFlag(const analyze_printf::PrintfSpecifier &FS, |
| const analyze_printf::OptionalFlag &flag, |
| const char *startSpecifier, |
| unsigned specifierLen) { |
| // Warn about pointless flag with a fixit removal. |
| const analyze_printf::PrintfConversionSpecifier &CS = |
| FS.getConversionSpecifier(); |
| EmitFormatDiagnostic(S.PDiag(diag::warn_printf_nonsensical_flag) |
| << flag.toString() << CS.toString(), |
| getLocationOfByte(flag.getPosition()), |
| /*IsStringLocation*/true, |
| getSpecifierRange(startSpecifier, specifierLen), |
| FixItHint::CreateRemoval( |
| getSpecifierRange(flag.getPosition(), 1))); |
| } |
| |
| void CheckPrintfHandler::HandleIgnoredFlag( |
| const analyze_printf::PrintfSpecifier &FS, |
| const analyze_printf::OptionalFlag &ignoredFlag, |
| const analyze_printf::OptionalFlag &flag, |
| const char *startSpecifier, |
| unsigned specifierLen) { |
| // Warn about ignored flag with a fixit removal. |
| EmitFormatDiagnostic(S.PDiag(diag::warn_printf_ignored_flag) |
| << ignoredFlag.toString() << flag.toString(), |
| getLocationOfByte(ignoredFlag.getPosition()), |
| /*IsStringLocation*/true, |
| getSpecifierRange(startSpecifier, specifierLen), |
| FixItHint::CreateRemoval( |
| getSpecifierRange(ignoredFlag.getPosition(), 1))); |
| } |
| |
| // Determines if the specified is a C++ class or struct containing |
| // a member with the specified name and kind (e.g. a CXXMethodDecl named |
| // "c_str()"). |
| template<typename MemberKind> |
| static llvm::SmallPtrSet<MemberKind*, 1> |
| CXXRecordMembersNamed(StringRef Name, Sema &S, QualType Ty) { |
| const RecordType *RT = Ty->getAs<RecordType>(); |
| llvm::SmallPtrSet<MemberKind*, 1> Results; |
| |
| if (!RT) |
| return Results; |
| const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl()); |
| if (!RD) |
| return Results; |
| |
| LookupResult R(S, &S.PP.getIdentifierTable().get(Name), SourceLocation(), |
| Sema::LookupMemberName); |
| |
| // We just need to include all members of the right kind turned up by the |
| // filter, at this point. |
| if (S.LookupQualifiedName(R, RT->getDecl())) |
| for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { |
| NamedDecl *decl = (*I)->getUnderlyingDecl(); |
| if (MemberKind *FK = dyn_cast<MemberKind>(decl)) |
| Results.insert(FK); |
| } |
| return Results; |
| } |
| |
| // Check if a (w)string was passed when a (w)char* was needed, and offer a |
| // better diagnostic if so. AT is assumed to be valid. |
| // Returns true when a c_str() conversion method is found. |
| bool CheckPrintfHandler::checkForCStrMembers( |
| const analyze_printf::ArgType &AT, const Expr *E, |
| const CharSourceRange &CSR) { |
| typedef llvm::SmallPtrSet<CXXMethodDecl*, 1> MethodSet; |
| |
| MethodSet Results = |
| CXXRecordMembersNamed<CXXMethodDecl>("c_str", S, E->getType()); |
| |
| for (MethodSet::iterator MI = Results.begin(), ME = Results.end(); |
| MI != ME; ++MI) { |
| const CXXMethodDecl *Method = *MI; |
| if (Method->getNumParams() == 0 && |
| AT.matchesType(S.Context, Method->getResultType())) { |
| // FIXME: Suggest parens if the expression needs them. |
| SourceLocation EndLoc = |
| S.getPreprocessor().getLocForEndOfToken(E->getLocEnd()); |
| S.Diag(E->getLocStart(), diag::note_printf_c_str) |
| << "c_str()" |
| << FixItHint::CreateInsertion(EndLoc, ".c_str()"); |
| return true; |
| } |
| } |
| |
| return false; |
| } |
| |
| bool |
| CheckPrintfHandler::HandlePrintfSpecifier(const analyze_printf::PrintfSpecifier |
| &FS, |
| const char *startSpecifier, |
| unsigned specifierLen) { |
| |
| using namespace analyze_format_string; |
| using namespace analyze_printf; |
| const PrintfConversionSpecifier &CS = FS.getConversionSpecifier(); |
| |
| if (FS.consumesDataArgument()) { |
| if (atFirstArg) { |
| atFirstArg = false; |
| usesPositionalArgs = FS.usesPositionalArg(); |
| } |
| else if (usesPositionalArgs != FS.usesPositionalArg()) { |
| HandlePositionalNonpositionalArgs(getLocationOfByte(CS.getStart()), |
| startSpecifier, specifierLen); |
| return false; |
| } |
| } |
| |
| // First check if the field width, precision, and conversion specifier |
| // have matching data arguments. |
| if (!HandleAmount(FS.getFieldWidth(), /* field width */ 0, |
| startSpecifier, specifierLen)) { |
| return false; |
| } |
| |
| if (!HandleAmount(FS.getPrecision(), /* precision */ 1, |
| startSpecifier, specifierLen)) { |
| return false; |
| } |
| |
| if (!CS.consumesDataArgument()) { |
| // FIXME: Technically specifying a precision or field width here |
| // makes no sense. Worth issuing a warning at some point. |
| return true; |
| } |
| |
| // Consume the argument. |
| unsigned argIndex = FS.getArgIndex(); |
| if (argIndex < NumDataArgs) { |
| // The check to see if the argIndex is valid will come later. |
| // We set the bit here because we may exit early from this |
| // function if we encounter some other error. |
| CoveredArgs.set(argIndex); |
| } |
| |
| // Check for using an Objective-C specific conversion specifier |
| // in a non-ObjC literal. |
| if (!ObjCContext && CS.isObjCArg()) { |
| return HandleInvalidPrintfConversionSpecifier(FS, startSpecifier, |
| specifierLen); |
| } |
| |
| // Check for invalid use of field width |
| if (!FS.hasValidFieldWidth()) { |
| HandleInvalidAmount(FS, FS.getFieldWidth(), /* field width */ 0, |
| startSpecifier, specifierLen); |
| } |
| |
| // Check for invalid use of precision |
| if (!FS.hasValidPrecision()) { |
| HandleInvalidAmount(FS, FS.getPrecision(), /* precision */ 1, |
| startSpecifier, specifierLen); |
| } |
| |
| // Check each flag does not conflict with any other component. |
| if (!FS.hasValidThousandsGroupingPrefix()) |
| HandleFlag(FS, FS.hasThousandsGrouping(), startSpecifier, specifierLen); |
| if (!FS.hasValidLeadingZeros()) |
| HandleFlag(FS, FS.hasLeadingZeros(), startSpecifier, specifierLen); |
| if (!FS.hasValidPlusPrefix()) |
| HandleFlag(FS, FS.hasPlusPrefix(), startSpecifier, specifierLen); |
| if (!FS.hasValidSpacePrefix()) |
| HandleFlag(FS, FS.hasSpacePrefix(), startSpecifier, specifierLen); |
| if (!FS.hasValidAlternativeForm()) |
| HandleFlag(FS, FS.hasAlternativeForm(), startSpecifier, specifierLen); |
| if (!FS.hasValidLeftJustified()) |
| HandleFlag(FS, FS.isLeftJustified(), startSpecifier, specifierLen); |
| |
| // Check that flags are not ignored by another flag |
| if (FS.hasSpacePrefix() && FS.hasPlusPrefix()) // ' ' ignored by '+' |
| HandleIgnoredFlag(FS, FS.hasSpacePrefix(), FS.hasPlusPrefix(), |
| startSpecifier, specifierLen); |
| if (FS.hasLeadingZeros() && FS.isLeftJustified()) // '0' ignored by '-' |
| HandleIgnoredFlag(FS, FS.hasLeadingZeros(), FS.isLeftJustified(), |
| startSpecifier, specifierLen); |
| |
| // Check the length modifier is valid with the given conversion specifier. |
| const LengthModifier &LM = FS.getLengthModifier(); |
| if (!FS.hasValidLengthModifier()) |
| EmitFormatDiagnostic(S.PDiag(diag::warn_format_nonsensical_length) |
| << LM.toString() << CS.toString(), |
| getLocationOfByte(LM.getStart()), |
| /*IsStringLocation*/true, |
| getSpecifierRange(startSpecifier, specifierLen), |
| FixItHint::CreateRemoval( |
| getSpecifierRange(LM.getStart(), |
| LM.getLength()))); |
| if (!FS.hasStandardLengthModifier()) |
| HandleNonStandardLengthModifier(LM, startSpecifier, specifierLen); |
| if (!FS.hasStandardConversionSpecifier(S.getLangOpts())) |
| HandleNonStandardConversionSpecifier(CS, startSpecifier, specifierLen); |
| if (!FS.hasStandardLengthConversionCombination()) |
| HandleNonStandardConversionSpecification(LM, CS, startSpecifier, |
| specifierLen); |
| |
| // The remaining checks depend on the data arguments. |
| if (HasVAListArg) |
| return true; |
| |
| if (!CheckNumArgs(FS, CS, startSpecifier, specifierLen, argIndex)) |
| return false; |
| |
| const Expr *Arg = getDataArg(argIndex); |
| if (!Arg) |
| return true; |
| |
| return checkFormatExpr(FS, startSpecifier, specifierLen, Arg); |
| } |
| |
| bool |
| CheckPrintfHandler::checkFormatExpr(const analyze_printf::PrintfSpecifier &FS, |
| const char *StartSpecifier, |
| unsigned SpecifierLen, |
| const Expr *E) { |
| using namespace analyze_format_string; |
| using namespace analyze_printf; |
| // Now type check the data expression that matches the |
| // format specifier. |
| const analyze_printf::ArgType &AT = FS.getArgType(S.Context, |
| ObjCContext); |
| if (!AT.isValid()) |
| return true; |
| if (AT.matchesType(S.Context, E->getType())) |
| return true; |
| |
| // Look through argument promotions for our error message's reported type. |
| // This includes the integral and floating promotions, but excludes array |
| // and function pointer decay; seeing that an argument intended to be a |
| // string has type 'char [6]' is probably more confusing than 'char *'. |
| if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) { |
| if (ICE->getCastKind() == CK_IntegralCast || |
| ICE->getCastKind() == CK_FloatingCast) { |
| E = ICE->getSubExpr(); |
| |
| // Check if we didn't match because of an implicit cast from a 'char' |
| // or 'short' to an 'int'. This is done because printf is a varargs |
| // function. |
| if (ICE->getType() == S.Context.IntTy || |
| ICE->getType() == S.Context.UnsignedIntTy) { |
| // All further checking is done on the subexpression. |
| if (AT.matchesType(S.Context, E->getType())) |
| return true; |
| } |
| } |
| } |
| |
| // We may be able to offer a FixItHint if it is a supported type. |
| PrintfSpecifier fixedFS = FS; |
| bool success = fixedFS.fixType(E->getType(), S.getLangOpts(), |
| S.Context, ObjCContext); |
| |
| if (success) { |
| // Get the fix string from the fixed format specifier |
| SmallString<16> buf; |
| llvm::raw_svector_ostream os(buf); |
| fixedFS.toString(os); |
| |
| EmitFormatDiagnostic( |
| S.PDiag(diag::warn_printf_conversion_argument_type_mismatch) |
| << AT.getRepresentativeTypeName(S.Context) << E->getType() |
| << E->getSourceRange(), |
| E->getLocStart(), |
| /*IsStringLocation*/false, |
| getSpecifierRange(StartSpecifier, SpecifierLen), |
| FixItHint::CreateReplacement( |
| getSpecifierRange(StartSpecifier, SpecifierLen), |
| os.str())); |
| } else { |
| const CharSourceRange &CSR = getSpecifierRange(StartSpecifier, |
| SpecifierLen); |
| // Since the warning for passing non-POD types to variadic functions |
| // was deferred until now, we emit a warning for non-POD |
| // arguments here. |
| if (S.isValidVarArgType(E->getType()) == Sema::VAK_Invalid) { |
| unsigned DiagKind; |
| if (E->getType()->isObjCObjectType()) |
| DiagKind = diag::err_cannot_pass_objc_interface_to_vararg_format; |
| else |
| DiagKind = diag::warn_non_pod_vararg_with_format_string; |
| |
| EmitFormatDiagnostic( |
| S.PDiag(DiagKind) |
| << S.getLangOpts().CPlusPlus0x |
| << E->getType() |
| << CallType |
| << AT.getRepresentativeTypeName(S.Context) |
| << CSR |
| << E->getSourceRange(), |
| E->getLocStart(), /*IsStringLocation*/false, CSR); |
| |
| checkForCStrMembers(AT, E, CSR); |
| } else |
| EmitFormatDiagnostic( |
| S.PDiag(diag::warn_printf_conversion_argument_type_mismatch) |
| << AT.getRepresentativeTypeName(S.Context) << E->getType() |
| << CSR |
| << E->getSourceRange(), |
| E->getLocStart(), /*IsStringLocation*/false, CSR); |
| } |
| |
| return true; |
| } |
| |
| //===--- CHECK: Scanf format string checking ------------------------------===// |
| |
| namespace { |
| class CheckScanfHandler : public CheckFormatHandler { |
| public: |
| CheckScanfHandler(Sema &s, const StringLiteral *fexpr, |
| const Expr *origFormatExpr, unsigned firstDataArg, |
| unsigned numDataArgs, const char *beg, bool hasVAListArg, |
| Expr **Args, unsigned NumArgs, |
| unsigned formatIdx, bool inFunctionCall, |
| Sema::VariadicCallType CallType) |
| : CheckFormatHandler(s, fexpr, origFormatExpr, firstDataArg, |
| numDataArgs, beg, hasVAListArg, |
| Args, NumArgs, formatIdx, inFunctionCall, CallType) |
| {} |
| |
| bool HandleScanfSpecifier(const analyze_scanf::ScanfSpecifier &FS, |
| const char *startSpecifier, |
| unsigned specifierLen); |
| |
| bool HandleInvalidScanfConversionSpecifier( |
| const analyze_scanf::ScanfSpecifier &FS, |
| const char *startSpecifier, |
| unsigned specifierLen); |
| |
| void HandleIncompleteScanList(const char *start, const char *end); |
| }; |
| } |
| |
| void CheckScanfHandler::HandleIncompleteScanList(const char *start, |
| const char *end) { |
| EmitFormatDiagnostic(S.PDiag(diag::warn_scanf_scanlist_incomplete), |
| getLocationOfByte(end), /*IsStringLocation*/true, |
| getSpecifierRange(start, end - start)); |
| } |
| |
| bool CheckScanfHandler::HandleInvalidScanfConversionSpecifier( |
| const analyze_scanf::ScanfSpecifier &FS, |
| const char *startSpecifier, |
| unsigned specifierLen) { |
| |
| const analyze_scanf::ScanfConversionSpecifier &CS = |
| FS.getConversionSpecifier(); |
| |
| return HandleInvalidConversionSpecifier(FS.getArgIndex(), |
| getLocationOfByte(CS.getStart()), |
| startSpecifier, specifierLen, |
| CS.getStart(), CS.getLength()); |
| } |
| |
| bool CheckScanfHandler::HandleScanfSpecifier( |
| const analyze_scanf::ScanfSpecifier &FS, |
| const char *startSpecifier, |
| unsigned specifierLen) { |
| |
| using namespace analyze_scanf; |
| using namespace analyze_format_string; |
| |
| const ScanfConversionSpecifier &CS = FS.getConversionSpecifier(); |
| |
| // Handle case where '%' and '*' don't consume an argument. These shouldn't |
| // be used to decide if we are using positional arguments consistently. |
| if (FS.consumesDataArgument()) { |
| if (atFirstArg) { |
| atFirstArg = false; |
| usesPositionalArgs = FS.usesPositionalArg(); |
| } |
| else if (usesPositionalArgs != FS.usesPositionalArg()) { |
| HandlePositionalNonpositionalArgs(getLocationOfByte(CS.getStart()), |
| startSpecifier, specifierLen); |
| return false; |
| } |
| } |
| |
| // Check if the field with is non-zero. |
| const OptionalAmount &Amt = FS.getFieldWidth(); |
| if (Amt.getHowSpecified() == OptionalAmount::Constant) { |
| if (Amt.getConstantAmount() == 0) { |
| const CharSourceRange &R = getSpecifierRange(Amt.getStart(), |
| Amt.getConstantLength()); |
| EmitFormatDiagnostic(S.PDiag(diag::warn_scanf_nonzero_width), |
| getLocationOfByte(Amt.getStart()), |
| /*IsStringLocation*/true, R, |
| FixItHint::CreateRemoval(R)); |
| } |
| } |
| |
| if (!FS.consumesDataArgument()) { |
| // FIXME: Technically specifying a precision or field width here |
| // makes no sense. Worth issuing a warning at some point. |
| return true; |
| } |
| |
| // Consume the argument. |
| unsigned argIndex = FS.getArgIndex(); |
| if (argIndex < NumDataArgs) { |
| // The check to see if the argIndex is valid will come later. |
| // We set the bit here because we may exit early from this |
| // function if we encounter some other error. |
| CoveredArgs.set(argIndex); |
| } |
| |
| // Check the length modifier is valid with the given conversion specifier. |
| const LengthModifier &LM = FS.getLengthModifier(); |
| if (!FS.hasValidLengthModifier()) { |
| const CharSourceRange &R = getSpecifierRange(LM.getStart(), LM.getLength()); |
| EmitFormatDiagnostic(S.PDiag(diag::warn_format_nonsensical_length) |
| << LM.toString() << CS.toString() |
| << getSpecifierRange(startSpecifier, specifierLen), |
| getLocationOfByte(LM.getStart()), |
| /*IsStringLocation*/true, R, |
| FixItHint::CreateRemoval(R)); |
| } |
| |
| if (!FS.hasStandardLengthModifier()) |
| HandleNonStandardLengthModifier(LM, startSpecifier, specifierLen); |
| if (!FS.hasStandardConversionSpecifier(S.getLangOpts())) |
| HandleNonStandardConversionSpecifier(CS, startSpecifier, specifierLen); |
| if (!FS.hasStandardLengthConversionCombination()) |
| HandleNonStandardConversionSpecification(LM, CS, startSpecifier, |
| specifierLen); |
| |
| // The remaining checks depend on the data arguments. |
| if (HasVAListArg) |
| return true; |
| |
| if (!CheckNumArgs(FS, CS, startSpecifier, specifierLen, argIndex)) |
| return false; |
| |
| // Check that the argument type matches the format specifier. |
| const Expr *Ex = getDataArg(argIndex); |
| if (!Ex) |
| return true; |
| |
| const analyze_format_string::ArgType &AT = FS.getArgType(S.Context); |
| if (AT.isValid() && !AT.matchesType(S.Context, Ex->getType())) { |
| ScanfSpecifier fixedFS = FS; |
| bool success = fixedFS.fixType(Ex->getType(), S.getLangOpts(), |
| S.Context); |
| |
| if (success) { |
| // Get the fix string from the fixed format specifier. |
| SmallString<128> buf; |
| llvm::raw_svector_ostream os(buf); |
| fixedFS.toString(os); |
| |
| EmitFormatDiagnostic( |
| S.PDiag(diag::warn_printf_conversion_argument_type_mismatch) |
| << AT.getRepresentativeTypeName(S.Context) << Ex->getType() |
| << Ex->getSourceRange(), |
| Ex->getLocStart(), |
| /*IsStringLocation*/false, |
| getSpecifierRange(startSpecifier, specifierLen), |
| FixItHint::CreateReplacement( |
| getSpecifierRange(startSpecifier, specifierLen), |
| os.str())); |
| } else { |
| EmitFormatDiagnostic( |
| S.PDiag(diag::warn_printf_conversion_argument_type_mismatch) |
| << AT.getRepresentativeTypeName(S.Context) << Ex->getType() |
| << Ex->getSourceRange(), |
| Ex->getLocStart(), |
| /*IsStringLocation*/false, |
| getSpecifierRange(startSpecifier, specifierLen)); |
| } |
| } |
| |
| return true; |
| } |
| |
| void Sema::CheckFormatString(const StringLiteral *FExpr, |
| const Expr *OrigFormatExpr, |
| Expr **Args, unsigned NumArgs, |
| bool HasVAListArg, unsigned format_idx, |
| unsigned firstDataArg, FormatStringType Type, |
| bool inFunctionCall, VariadicCallType CallType) { |
| |
| // CHECK: is the format string a wide literal? |
| if (!FExpr->isAscii() && !FExpr->isUTF8()) { |
| CheckFormatHandler::EmitFormatDiagnostic( |
| *this, inFunctionCall, Args[format_idx], |
| PDiag(diag::warn_format_string_is_wide_literal), FExpr->getLocStart(), |
| /*IsStringLocation*/true, OrigFormatExpr->getSourceRange()); |
| return; |
| } |
| |
| // Str - The format string. NOTE: this is NOT null-terminated! |
| StringRef StrRef = FExpr->getString(); |
| const char *Str = StrRef.data(); |
| unsigned StrLen = StrRef.size(); |
| const unsigned numDataArgs = NumArgs - firstDataArg; |
| |
| // CHECK: empty format string? |
| if (StrLen == 0 && numDataArgs > 0) { |
| CheckFormatHandler::EmitFormatDiagnostic( |
| *this, inFunctionCall, Args[format_idx], |
| PDiag(diag::warn_empty_format_string), FExpr->getLocStart(), |
| /*IsStringLocation*/true, OrigFormatExpr->getSourceRange()); |
| return; |
| } |
| |
| if (Type == FST_Printf || Type == FST_NSString) { |
| CheckPrintfHandler H(*this, FExpr, OrigFormatExpr, firstDataArg, |
| numDataArgs, (Type == FST_NSString), |
| Str, HasVAListArg, Args, NumArgs, format_idx, |
| inFunctionCall, CallType); |
| |
| if (!analyze_format_string::ParsePrintfString(H, Str, Str + StrLen, |
| getLangOpts())) |
| H.DoneProcessing(); |
| } else if (Type == FST_Scanf) { |
| CheckScanfHandler H(*this, FExpr, OrigFormatExpr, firstDataArg, numDataArgs, |
| Str, HasVAListArg, Args, NumArgs, format_idx, |
| inFunctionCall, CallType); |
| |
| if (!analyze_format_string::ParseScanfString(H, Str, Str + StrLen, |
| getLangOpts())) |
| H.DoneProcessing(); |
| } // TODO: handle other formats |
| } |
| |
| //===--- CHECK: Standard memory functions ---------------------------------===// |
| |
| /// \brief Determine whether the given type is a dynamic class type (e.g., |
| /// whether it has a vtable). |
| static bool isDynamicClassType(QualType T) { |
| if (CXXRecordDecl *Record = T->getAsCXXRecordDecl()) |
| if (CXXRecordDecl *Definition = Record->getDefinition()) |
| if (Definition->isDynamicClass()) |
| return true; |
| |
| return false; |
| } |
| |
| /// \brief If E is a sizeof expression, returns its argument expression, |
| /// otherwise returns NULL. |
| static const Expr *getSizeOfExprArg(const Expr* E) { |
| if (const UnaryExprOrTypeTraitExpr *SizeOf = |
| dyn_cast<UnaryExprOrTypeTraitExpr>(E)) |
| if (SizeOf->getKind() == clang::UETT_SizeOf && !SizeOf->isArgumentType()) |
| return SizeOf->getArgumentExpr()->IgnoreParenImpCasts(); |
| |
| return 0; |
| } |
| |
| /// \brief If E is a sizeof expression, returns its argument type. |
| static QualType getSizeOfArgType(const Expr* E) { |
| if (const UnaryExprOrTypeTraitExpr *SizeOf = |
| dyn_cast<UnaryExprOrTypeTraitExpr>(E)) |
| if (SizeOf->getKind() == clang::UETT_SizeOf) |
| return SizeOf->getTypeOfArgument(); |
| |
| return QualType(); |
| } |
| |
| /// \brief Check for dangerous or invalid arguments to memset(). |
| /// |
| /// This issues warnings on known problematic, dangerous or unspecified |
| /// arguments to the standard 'memset', 'memcpy', 'memmove', and 'memcmp' |
| /// function calls. |
| /// |
| /// \param Call The call expression to diagnose. |
| void Sema::CheckMemaccessArguments(const CallExpr *Call, |
| unsigned BId, |
| IdentifierInfo *FnName) { |
| assert(BId != 0); |
| |
| // It is possible to have a non-standard definition of memset. Validate |
| // we have enough arguments, and if not, abort further checking. |
| unsigned ExpectedNumArgs = (BId == Builtin::BIstrndup ? 2 : 3); |
| if (Call->getNumArgs() < ExpectedNumArgs) |
| return; |
| |
| unsigned LastArg = (BId == Builtin::BImemset || |
| BId == Builtin::BIstrndup ? 1 : 2); |
| unsigned LenArg = (BId == Builtin::BIstrndup ? 1 : 2); |
| const Expr *LenExpr = Call->getArg(LenArg)->IgnoreParenImpCasts(); |
| |
| // We have special checking when the length is a sizeof expression. |
| QualType SizeOfArgTy = getSizeOfArgType(LenExpr); |
| const Expr *SizeOfArg = getSizeOfExprArg(LenExpr); |
| llvm::FoldingSetNodeID SizeOfArgID; |
| |
| for (unsigned ArgIdx = 0; ArgIdx != LastArg; ++ArgIdx) { |
| const Expr *Dest = Call->getArg(ArgIdx)->IgnoreParenImpCasts(); |
| SourceRange ArgRange = Call->getArg(ArgIdx)->getSourceRange(); |
| |
| QualType DestTy = Dest->getType(); |
| if (const PointerType *DestPtrTy = DestTy->getAs<PointerType>()) { |
| QualType PointeeTy = DestPtrTy->getPointeeType(); |
| |
| // Never warn about void type pointers. This can be used to suppress |
| // false positives. |
| if (PointeeTy->isVoidType()) |
| continue; |
| |
| // Catch "memset(p, 0, sizeof(p))" -- needs to be sizeof(*p). Do this by |
| // actually comparing the expressions for equality. Because computing the |
| // expression IDs can be expensive, we only do this if the diagnostic is |
| // enabled. |
| if (SizeOfArg && |
| Diags.getDiagnosticLevel(diag::warn_sizeof_pointer_expr_memaccess, |
| SizeOfArg->getExprLoc())) { |
| // We only compute IDs for expressions if the warning is enabled, and |
| // cache the sizeof arg's ID. |
| if (SizeOfArgID == llvm::FoldingSetNodeID()) |
| SizeOfArg->Profile(SizeOfArgID, Context, true); |
| llvm::FoldingSetNodeID DestID; |
| Dest->Profile(DestID, Context, true); |
| if (DestID == SizeOfArgID) { |
| // TODO: For strncpy() and friends, this could suggest sizeof(dst) |
| // over sizeof(src) as well. |
| unsigned ActionIdx = 0; // Default is to suggest dereferencing. |
| StringRef ReadableName = FnName->getName(); |
| |
| if (const UnaryOperator *UnaryOp = dyn_cast<UnaryOperator>(Dest)) |
| if (UnaryOp->getOpcode() == UO_AddrOf) |
| ActionIdx = 1; // If its an address-of operator, just remove it. |
| if (Context.getTypeSize(PointeeTy) == Context.getCharWidth()) |
| ActionIdx = 2; // If the pointee's size is sizeof(char), |
| // suggest an explicit length. |
| |
| // If the function is defined as a builtin macro, do not show macro |
| // expansion. |
| SourceLocation SL = SizeOfArg->getExprLoc(); |
| SourceRange DSR = Dest->getSourceRange(); |
| SourceRange SSR = SizeOfArg->getSourceRange(); |
| SourceManager &SM = PP.getSourceManager(); |
| |
| if (SM.isMacroArgExpansion(SL)) { |
| ReadableName = Lexer::getImmediateMacroName(SL, SM, LangOpts); |
| SL = SM.getSpellingLoc(SL); |
| DSR = SourceRange(SM.getSpellingLoc(DSR.getBegin()), |
| SM.getSpellingLoc(DSR.getEnd())); |
| SSR = SourceRange(SM.getSpellingLoc(SSR.getBegin()), |
| SM.getSpellingLoc(SSR.getEnd())); |
| } |
| |
| DiagRuntimeBehavior(SL, SizeOfArg, |
| PDiag(diag::warn_sizeof_pointer_expr_memaccess) |
| << ReadableName |
| << PointeeTy |
| << DestTy |
| << DSR |
| << SSR); |
| DiagRuntimeBehavior(SL, SizeOfArg, |
| PDiag(diag::warn_sizeof_pointer_expr_memaccess_note) |
| << ActionIdx |
| << SSR); |
| |
| break; |
| } |
| } |
| |
| // Also check for cases where the sizeof argument is the exact same |
| // type as the memory argument, and where it points to a user-defined |
| // record type. |
| if (SizeOfArgTy != QualType()) { |
| if (PointeeTy->isRecordType() && |
| Context.typesAreCompatible(SizeOfArgTy, DestTy)) { |
| DiagRuntimeBehavior(LenExpr->getExprLoc(), Dest, |
| PDiag(diag::warn_sizeof_pointer_type_memaccess) |
| << FnName << SizeOfArgTy << ArgIdx |
| << PointeeTy << Dest->getSourceRange() |
| << LenExpr->getSourceRange()); |
| break; |
| } |
| } |
| |
| // Always complain about dynamic classes. |
| if (isDynamicClassType(PointeeTy)) { |
| |
| unsigned OperationType = 0; |
| // "overwritten" if we're warning about the destination for any call |
| // but memcmp; otherwise a verb appropriate to the call. |
| if (ArgIdx != 0 || BId == Builtin::BImemcmp) { |
| if (BId == Builtin::BImemcpy) |
| OperationType = 1; |
| else if(BId == Builtin::BImemmove) |
| OperationType = 2; |
| else if (BId == Builtin::BImemcmp) |
| OperationType = 3; |
| } |
| |
| DiagRuntimeBehavior( |
| Dest->getExprLoc(), Dest, |
| PDiag(diag::warn_dyn_class_memaccess) |
| << (BId == Builtin::BImemcmp ? ArgIdx + 2 : ArgIdx) |
| << FnName << PointeeTy |
| << OperationType |
| << Call->getCallee()->getSourceRange()); |
| } else if (PointeeTy.hasNonTrivialObjCLifetime() && |
| BId != Builtin::BImemset) |
| DiagRuntimeBehavior( |
| Dest->getExprLoc(), Dest, |
| PDiag(diag::warn_arc_object_memaccess) |
| << ArgIdx << FnName << PointeeTy |
| << Call->getCallee()->getSourceRange()); |
| else |
| continue; |
| |
| DiagRuntimeBehavior( |
| Dest->getExprLoc(), Dest, |
| PDiag(diag::note_bad_memaccess_silence) |
| << FixItHint::CreateInsertion(ArgRange.getBegin(), "(void*)")); |
| break; |
| } |
| } |
| } |
| |
| // A little helper routine: ignore addition and subtraction of integer literals. |
| // This intentionally does not ignore all integer constant expressions because |
| // we don't want to remove sizeof(). |
| static const Expr *ignoreLiteralAdditions(const Expr *Ex, ASTContext &Ctx) { |
| Ex = Ex->IgnoreParenCasts(); |
| |
| for (;;) { |
| const BinaryOperator * BO = dyn_cast<BinaryOperator>(Ex); |
| if (!BO || !BO->isAdditiveOp()) |
| break; |
| |
| const Expr *RHS = BO->getRHS()->IgnoreParenCasts(); |
| const Expr *LHS = BO->getLHS()->IgnoreParenCasts(); |
| |
| if (isa<IntegerLiteral>(RHS)) |
| Ex = LHS; |
| else if (isa<IntegerLiteral>(LHS)) |
| Ex = RHS; |
| else |
| break; |
| } |
| |
| return Ex; |
| } |
| |
| static bool isConstantSizeArrayWithMoreThanOneElement(QualType Ty, |
| ASTContext &Context) { |
| // Only handle constant-sized or VLAs, but not flexible members. |
| if (const ConstantArrayType *CAT = Context.getAsConstantArrayType(Ty)) { |
| // Only issue the FIXIT for arrays of size > 1. |
| if (CAT->getSize().getSExtValue() <= 1) |
| return false; |
| } else if (!Ty->isVariableArrayType()) { |
| return false; |
| } |
| return true; |
| } |
| |
| // Warn if the user has made the 'size' argument to strlcpy or strlcat |
| // be the size of the source, instead of the destination. |
| void Sema::CheckStrlcpycatArguments(const CallExpr *Call, |
| IdentifierInfo *FnName) { |
| |
| // Don't crash if the user has the wrong number of arguments |
| if (Call->getNumArgs() != 3) |
| return; |
| |
| const Expr *SrcArg = ignoreLiteralAdditions(Call->getArg(1), Context); |
| const Expr *SizeArg = ignoreLiteralAdditions(Call->getArg(2), Context); |
| const Expr *CompareWithSrc = NULL; |
| |
| // Look for 'strlcpy(dst, x, sizeof(x))' |
| if (const Expr *Ex = getSizeOfExprArg(SizeArg)) |
| CompareWithSrc = Ex; |
| else { |
| // Look for 'strlcpy(dst, x, strlen(x))' |
| if (const CallExpr *SizeCall = dyn_cast<CallExpr>(SizeArg)) { |
| if (SizeCall->isBuiltinCall() == Builtin::BIstrlen |
| && SizeCall->getNumArgs() == 1) |
| CompareWithSrc = ignoreLiteralAdditions(SizeCall->getArg(0), Context); |
| } |
| } |
| |
| if (!CompareWithSrc) |
| return; |
| |
| // Determine if the argument to sizeof/strlen is equal to the source |
| // argument. In principle there's all kinds of things you could do |
| // here, for instance creating an == expression and evaluating it with |
| // EvaluateAsBooleanCondition, but this uses a more direct technique: |
| const DeclRefExpr *SrcArgDRE = dyn_cast<DeclRefExpr>(SrcArg); |
| if (!SrcArgDRE) |
| return; |
| |
| const DeclRefExpr *CompareWithSrcDRE = dyn_cast<DeclRefExpr>(CompareWithSrc); |
| if (!CompareWithSrcDRE || |
| SrcArgDRE->getDecl() != CompareWithSrcDRE->getDecl()) |
| return; |
| |
| const Expr *OriginalSizeArg = Call->getArg(2); |
| Diag(CompareWithSrcDRE->getLocStart(), diag::warn_strlcpycat_wrong_size) |
| << OriginalSizeArg->getSourceRange() << FnName; |
| |
| // Output a FIXIT hint if the destination is an array (rather than a |
| // pointer to an array). This could be enhanced to handle some |
| // pointers if we know the actual size, like if DstArg is 'array+2' |
| // we could say 'sizeof(array)-2'. |
| const Expr *DstArg = Call->getArg(0)->IgnoreParenImpCasts(); |
| if (!isConstantSizeArrayWithMoreThanOneElement(DstArg->getType(), Context)) |
| return; |
| |
| SmallString<128> sizeString; |
| llvm::raw_svector_ostream OS(sizeString); |
| OS << "sizeof("; |
| DstArg->printPretty(OS, 0, getPrintingPolicy()); |
| OS << ")"; |
| |
| Diag(OriginalSizeArg->getLocStart(), diag::note_strlcpycat_wrong_size) |
| << FixItHint::CreateReplacement(OriginalSizeArg->getSourceRange(), |
| OS.str()); |
| } |
| |
| /// Check if two expressions refer to the same declaration. |
| static bool referToTheSameDecl(const Expr *E1, const Expr *E2) { |
| if (const DeclRefExpr *D1 = dyn_cast_or_null<DeclRefExpr>(E1)) |
| if (const DeclRefExpr *D2 = dyn_cast_or_null<DeclRefExpr>(E2)) |
| return D1->getDecl() == D2->getDecl(); |
| return false; |
| } |
| |
| static const Expr *getStrlenExprArg(const Expr *E) { |
| if (const CallExpr *CE = dyn_cast<CallExpr>(E)) { |
| const FunctionDecl *FD = CE->getDirectCallee(); |
| if (!FD || FD->getMemoryFunctionKind() != Builtin::BIstrlen) |
| return 0; |
| return CE->getArg(0)->IgnoreParenCasts(); |
| } |
| return 0; |
| } |
| |
| // Warn on anti-patterns as the 'size' argument to strncat. |
| // The correct size argument should look like following: |
| // strncat(dst, src, sizeof(dst) - strlen(dest) - 1); |
| void Sema::CheckStrncatArguments(const CallExpr *CE, |
| IdentifierInfo *FnName) { |
| // Don't crash if the user has the wrong number of arguments. |
| if (CE->getNumArgs() < 3) |
| return; |
| const Expr *DstArg = CE->getArg(0)->IgnoreParenCasts(); |
| const Expr *SrcArg = CE->getArg(1)->IgnoreParenCasts(); |
| const Expr *LenArg = CE->getArg(2)->IgnoreParenCasts(); |
| |
| // Identify common expressions, which are wrongly used as the size argument |
| // to strncat and may lead to buffer overflows. |
| unsigned PatternType = 0; |
| if (const Expr *SizeOfArg = getSizeOfExprArg(LenArg)) { |
| // - sizeof(dst) |
| if (referToTheSameDecl(SizeOfArg, DstArg)) |
| PatternType = 1; |
| // - sizeof(src) |
| else if (referToTheSameDecl(SizeOfArg, SrcArg)) |
| PatternType = 2; |
| } else if (const BinaryOperator *BE = dyn_cast<BinaryOperator>(LenArg)) { |
| if (BE->getOpcode() == BO_Sub) { |
| const Expr *L = BE->getLHS()->IgnoreParenCasts(); |
| const Expr *R = BE->getRHS()->IgnoreParenCasts(); |
| // - sizeof(dst) - strlen(dst) |
| if (referToTheSameDecl(DstArg, getSizeOfExprArg(L)) && |
| referToTheSameDecl(DstArg, getStrlenExprArg(R))) |
| PatternType = 1; |
| // - sizeof(src) - (anything) |
| else if (referToTheSameDecl(SrcArg, getSizeOfExprArg(L))) |
| PatternType = 2; |
| } |
| } |
| |
| if (PatternType == 0) |
| return; |
| |
| // Generate the diagnostic. |
| SourceLocation SL = LenArg->getLocStart(); |
| SourceRange SR = LenArg->getSourceRange(); |
| SourceManager &SM = PP.getSourceManager(); |
| |
| // If the function is defined as a builtin macro, do not show macro expansion. |
| if (SM.isMacroArgExpansion(SL)) { |
| SL = SM.getSpellingLoc(SL); |
| SR = SourceRange(SM.getSpellingLoc(SR.getBegin()), |
| SM.getSpellingLoc(SR.getEnd())); |
| } |
| |
| // Check if the destination is an array (rather than a pointer to an array). |
| QualType DstTy = DstArg->getType(); |
| bool isKnownSizeArray = isConstantSizeArrayWithMoreThanOneElement(DstTy, |
| Context); |
| if (!isKnownSizeArray) { |
| if (PatternType == 1) |
| Diag(SL, diag::warn_strncat_wrong_size) << SR; |
| else |
| Diag(SL, diag::warn_strncat_src_size) << SR; |
| return; |
| } |
| |
| if (PatternType == 1) |
| Diag(SL, diag::warn_strncat_large_size) << SR; |
| else |
| Diag(SL, diag::warn_strncat_src_size) << SR; |
| |
| SmallString<128> sizeString; |
| llvm::raw_svector_ostream OS(sizeString); |
| OS << "sizeof("; |
| DstArg->printPretty(OS, 0, getPrintingPolicy()); |
| OS << ") - "; |
| OS << "strlen("; |
| DstArg->printPretty(OS, 0, getPrintingPolicy()); |
| OS << ") - 1"; |
| |
| Diag(SL, diag::note_strncat_wrong_size) |
| << FixItHint::CreateReplacement(SR, OS.str()); |
| } |
| |
| //===--- CHECK: Return Address of Stack Variable --------------------------===// |
| |
| static Expr *EvalVal(Expr *E, SmallVectorImpl<DeclRefExpr *> &refVars, |
| Decl *ParentDecl); |
| static Expr *EvalAddr(Expr* E, SmallVectorImpl<DeclRefExpr *> &refVars, |
| Decl *ParentDecl); |
| |
| /// CheckReturnStackAddr - Check if a return statement returns the address |
| /// of a stack variable. |
| void |
| Sema::CheckReturnStackAddr(Expr *RetValExp, QualType lhsType, |
| SourceLocation ReturnLoc) { |
| |
| Expr *stackE = 0; |
| SmallVector<DeclRefExpr *, 8> refVars; |
| |
| // Perform checking for returned stack addresses, local blocks, |
| // label addresses or references to temporaries. |
| if (lhsType->isPointerType() || |
| (!getLangOpts().ObjCAutoRefCount && lhsType->isBlockPointerType())) { |
| stackE = EvalAddr(RetValExp, refVars, /*ParentDecl=*/0); |
| } else if (lhsType->isReferenceType()) { |
| stackE = EvalVal(RetValExp, refVars, /*ParentDecl=*/0); |
| } |
| |
| if (stackE == 0) |
| return; // Nothing suspicious was found. |
| |
| SourceLocation diagLoc; |
| SourceRange diagRange; |
| if (refVars.empty()) { |
| diagLoc = stackE->getLocStart(); |
| diagRange = stackE->getSourceRange(); |
| } else { |
| // We followed through a reference variable. 'stackE' contains the |
| // problematic expression but we will warn at the return statement pointing |
| // at the reference variable. We will later display the "trail" of |
| // reference variables using notes. |
| diagLoc = refVars[0]->getLocStart(); |
| diagRange = refVars[0]->getSourceRange(); |
| } |
| |
| if (DeclRefExpr *DR = dyn_cast<DeclRefExpr>(stackE)) { //address of local var. |
| Diag(diagLoc, lhsType->isReferenceType() ? diag::warn_ret_stack_ref |
| : diag::warn_ret_stack_addr) |
| << DR->getDecl()->getDeclName() << diagRange; |
| } else if (isa<BlockExpr>(stackE)) { // local block. |
| Diag(diagLoc, diag::err_ret_local_block) << diagRange; |
| } else if (isa<AddrLabelExpr>(stackE)) { // address of label. |
| Diag(diagLoc, diag::warn_ret_addr_label) << diagRange; |
| } else { // local temporary. |
| Diag(diagLoc, lhsType->isReferenceType() ? diag::warn_ret_local_temp_ref |
| : diag::warn_ret_local_temp_addr) |
| << diagRange; |
| } |
| |
| // Display the "trail" of reference variables that we followed until we |
| // found the problematic expression using notes. |
| for (unsigned i = 0, e = refVars.size(); i != e; ++i) { |
| VarDecl *VD = cast<VarDecl>(refVars[i]->getDecl()); |
| // If this var binds to another reference var, show the range of the next |
| // var, otherwise the var binds to the problematic expression, in which case |
| // show the range of the expression. |
| SourceRange range = (i < e-1) ? refVars[i+1]->getSourceRange() |
| : stackE->getSourceRange(); |
| Diag(VD->getLocation(), diag::note_ref_var_local_bind) |
| << VD->getDeclName() << range; |
| } |
| } |
| |
| /// EvalAddr - EvalAddr and EvalVal are mutually recursive functions that |
| /// check if the expression in a return statement evaluates to an address |
| /// to a location on the stack, a local block, an address of a label, or a |
| /// reference to local temporary. The recursion is used to traverse the |
| /// AST of the return expression, with recursion backtracking when we |
| /// encounter a subexpression that (1) clearly does not lead to one of the |
| /// above problematic expressions (2) is something we cannot determine leads to |
| /// a problematic expression based on such local checking. |
| /// |
| /// Both EvalAddr and EvalVal follow through reference variables to evaluate |
| /// the expression that they point to. Such variables are added to the |
| /// 'refVars' vector so that we know what the reference variable "trail" was. |
| /// |
| /// EvalAddr processes expressions that are pointers that are used as |
| /// references (and not L-values). EvalVal handles all other values. |
| /// At the base case of the recursion is a check for the above problematic |
| /// expressions. |
| /// |
| /// This implementation handles: |
| /// |
| /// * pointer-to-pointer casts |
| /// * implicit conversions from array references to pointers |
| /// * taking the address of fields |
| /// * arbitrary interplay between "&" and "*" operators |
| /// * pointer arithmetic from an address of a stack variable |
| /// * taking the address of an array element where the array is on the stack |
| static Expr *EvalAddr(Expr *E, SmallVectorImpl<DeclRefExpr *> &refVars, |
| Decl *ParentDecl) { |
| if (E->isTypeDependent()) |
| return NULL; |
| |
| // We should only be called for evaluating pointer expressions. |
| assert((E->getType()->isAnyPointerType() || |
| E->getType()->isBlockPointerType() || |
| E->getType()->isObjCQualifiedIdType()) && |
| "EvalAddr only works on pointers"); |
| |
| E = E->IgnoreParens(); |
| |
| // Our "symbolic interpreter" is just a dispatch off the currently |
| // viewed AST node. We then recursively traverse the AST by calling |
| // EvalAddr and EvalVal appropriately. |
| switch (E->getStmtClass()) { |
| case Stmt::DeclRefExprClass: { |
| DeclRefExpr *DR = cast<DeclRefExpr>(E); |
| |
| if (VarDecl *V = dyn_cast<VarDecl>(DR->getDecl())) |
| // If this is a reference variable, follow through to the expression that |
| // it points to. |
| if (V->hasLocalStorage() && |
| V->getType()->isReferenceType() && V->hasInit()) { |
| // Add the reference variable to the "trail". |
| refVars.push_back(DR); |
| return EvalAddr(V->getInit(), refVars, ParentDecl); |
| } |
| |
| return NULL; |
| } |
| |
| case Stmt::UnaryOperatorClass: { |
| // The only unary operator that make sense to handle here |
| // is AddrOf. All others don't make sense as pointers. |
| UnaryOperator *U = cast<UnaryOperator>(E); |
| |
| if (U->getOpcode() == UO_AddrOf) |
| return EvalVal(U->getSubExpr(), refVars, ParentDecl); |
| else |
| return NULL; |
| } |
| |
| case Stmt::BinaryOperatorClass: { |
| // Handle pointer arithmetic. All other binary operators are not valid |
| // in this context. |
| BinaryOperator *B = cast<BinaryOperator>(E); |
| BinaryOperatorKind op = B->getOpcode(); |
| |
| if (op != BO_Add && op != BO_Sub) |
| return NULL; |
| |
| Expr *Base = B->getLHS(); |
| |
| // Determine which argument is the real pointer base. It could be |
| // the RHS argument instead of the LHS. |
| if (!Base->getType()->isPointerType()) Base = B->getRHS(); |
| |
| assert (Base->getType()->isPointerType()); |
| return EvalAddr(Base, refVars, ParentDecl); |
| } |
| |
| // For conditional operators we need to see if either the LHS or RHS are |
| // valid DeclRefExpr*s. If one of them is valid, we return it. |
| case Stmt::ConditionalOperatorClass: { |
| ConditionalOperator *C = cast<ConditionalOperator>(E); |
| |
| // Handle the GNU extension for missing LHS. |
| if (Expr *lhsExpr = C->getLHS()) { |
| // In C++, we can have a throw-expression, which has 'void' type. |
| if (!lhsExpr->getType()->isVoidType()) |
| if (Expr* LHS = EvalAddr(lhsExpr, refVars, ParentDecl)) |
| return LHS; |
| } |
| |
| // In C++, we can have a throw-expression, which has 'void' type. |
| if (C->getRHS()->getType()->isVoidType()) |
| return NULL; |
| |
| return EvalAddr(C->getRHS(), refVars, ParentDecl); |
| } |
| |
| case Stmt::BlockExprClass: |
| if (cast<BlockExpr>(E)->getBlockDecl()->hasCaptures()) |
| return E; // local block. |
| return NULL; |
| |
| case Stmt::AddrLabelExprClass: |
| return E; // address of label. |
| |
| case Stmt::ExprWithCleanupsClass: |
| return EvalAddr(cast<ExprWithCleanups>(E)->getSubExpr(), refVars, |
| ParentDecl); |
| |
| // For casts, we need to handle conversions from arrays to |
| // pointer values, and pointer-to-pointer conversions. |
| case Stmt::ImplicitCastExprClass: |
| case Stmt::CStyleCastExprClass: |
| case Stmt::CXXFunctionalCastExprClass: |
| case Stmt::ObjCBridgedCastExprClass: |
| case Stmt::CXXStaticCastExprClass: |
| case Stmt::CXXDynamicCastExprClass: |
| case Stmt::CXXConstCastExprClass: |
| case Stmt::CXXReinterpretCastExprClass: { |
| Expr* SubExpr = cast<CastExpr>(E)->getSubExpr(); |
| switch (cast<CastExpr>(E)->getCastKind()) { |
| case CK_BitCast: |
| case CK_LValueToRValue: |
| case CK_NoOp: |
| case CK_BaseToDerived: |
| case CK_DerivedToBase: |
| case CK_UncheckedDerivedToBase: |
| case CK_Dynamic: |
| case CK_CPointerToObjCPointerCast: |
| case CK_BlockPointerToObjCPointerCast: |
| case CK_AnyPointerToBlockPointerCast: |
| return EvalAddr(SubExpr, refVars, ParentDecl); |
| |
| case CK_ArrayToPointerDecay: |
| return EvalVal(SubExpr, refVars, ParentDecl); |
| |
| default: |
| return 0; |
| } |
| } |
| |
| case Stmt::MaterializeTemporaryExprClass: |
| if (Expr *Result = EvalAddr( |
| cast<MaterializeTemporaryExpr>(E)->GetTemporaryExpr(), |
| refVars, ParentDecl)) |
| return Result; |
| |
| return E; |
| |
| // Everything else: we simply don't reason about them. |
| default: |
| return NULL; |
| } |
| } |
| |
| |
| /// EvalVal - This function is complements EvalAddr in the mutual recursion. |
| /// See the comments for EvalAddr for more details. |
| static Expr *EvalVal(Expr *E, SmallVectorImpl<DeclRefExpr *> &refVars, |
| Decl *ParentDecl) { |
| do { |
| // We should only be called for evaluating non-pointer expressions, or |
| // expressions with a pointer type that are not used as references but instead |
| // are l-values (e.g., DeclRefExpr with a pointer type). |
| |
| // Our "symbolic interpreter" is just a dispatch off the currently |
| // viewed AST node. We then recursively traverse the AST by calling |
| // EvalAddr and EvalVal appropriately. |
| |
| E = E->IgnoreParens(); |
| switch (E->getStmtClass()) { |
| case Stmt::ImplicitCastExprClass: { |
| ImplicitCastExpr *IE = cast<ImplicitCastExpr>(E); |
| if (IE->getValueKind() == VK_LValue) { |
| E = IE->getSubExpr(); |
| continue; |
| } |
| return NULL; |
| } |
| |
| case Stmt::ExprWithCleanupsClass: |
| return EvalVal(cast<ExprWithCleanups>(E)->getSubExpr(), refVars,ParentDecl); |
| |
| case Stmt::DeclRefExprClass: { |
| // When we hit a DeclRefExpr we are looking at code that refers to a |
| // variable's name. If it's not a reference variable we check if it has |
| // local storage within the function, and if so, return the expression. |
| DeclRefExpr *DR = cast<DeclRefExpr>(E); |
| |
| if (VarDecl *V = dyn_cast<VarDecl>(DR->getDecl())) { |
| // Check if it refers to itself, e.g. "int& i = i;". |
| if (V == ParentDecl) |
| return DR; |
| |
| if (V->hasLocalStorage()) { |
| if (!V->getType()->isReferenceType()) |
| return DR; |
| |
| // Reference variable, follow through to the expression that |
| // it points to. |
| if (V->hasInit()) { |
| // Add the reference variable to the "trail". |
| refVars.push_back(DR); |
| return EvalVal(V->getInit(), refVars, V); |
| } |
| } |
| } |
| |
| return NULL; |
| } |
| |
| case Stmt::UnaryOperatorClass: { |
| // The only unary operator that make sense to handle here |
| // is Deref. All others don't resolve to a "name." This includes |
| // handling all sorts of rvalues passed to a unary operator. |
| UnaryOperator *U = cast<UnaryOperator>(E); |
| |
| if (U->getOpcode() == UO_Deref) |
| return EvalAddr(U->getSubExpr(), refVars, ParentDecl); |
| |
| return NULL; |
| } |
| |
| case Stmt::ArraySubscriptExprClass: { |
| // Array subscripts are potential references to data on the stack. We |
| // retrieve the DeclRefExpr* for the array variable if it indeed |
| // has local storage. |
| return EvalAddr(cast<ArraySubscriptExpr>(E)->getBase(), refVars,ParentDecl); |
| } |
| |
| case Stmt::ConditionalOperatorClass: { |
| // For conditional operators we need to see if either the LHS or RHS are |
| // non-NULL Expr's. If one is non-NULL, we return it. |
| ConditionalOperator *C = cast<ConditionalOperator>(E); |
| |
| // Handle the GNU extension for missing LHS. |
| if (Expr *lhsExpr = C->getLHS()) |
| if (Expr *LHS = EvalVal(lhsExpr, refVars, ParentDecl)) |
| return LHS; |
| |
| return EvalVal(C->getRHS(), refVars, ParentDecl); |
| } |
| |
| // Accesses to members are potential references to data on the stack. |
| case Stmt::MemberExprClass: { |
| MemberExpr *M = cast<MemberExpr>(E); |
| |
| // Check for indirect access. We only want direct field accesses. |
| if (M->isArrow()) |
| return NULL; |
| |
| // Check whether the member type is itself a reference, in which case |
| // we're not going to refer to the member, but to what the member refers to. |
| if (M->getMemberDecl()->getType()->isReferenceType()) |
| return NULL; |
| |
| return EvalVal(M->getBase(), refVars, ParentDecl); |
| } |
| |
| case Stmt::MaterializeTemporaryExprClass: |
| if (Expr *Result = EvalVal( |
| cast<MaterializeTemporaryExpr>(E)->GetTemporaryExpr(), |
| refVars, ParentDecl)) |
| return Result; |
| |
| return E; |
| |
| default: |
| // Check that we don't return or take the address of a reference to a |
| // temporary. This is only useful in C++. |
| if (!E->isTypeDependent() && E->isRValue()) |
| return E; |
| |
| // Everything else: we simply don't reason about them. |
| return NULL; |
| } |
| } while (true); |
| } |
| |
| //===--- CHECK: Floating-Point comparisons (-Wfloat-equal) ---------------===// |
| |
| /// Check for comparisons of floating point operands using != and ==. |
| /// Issue a warning if these are no self-comparisons, as they are not likely |
| /// to do what the programmer intended. |
| void Sema::CheckFloatComparison(SourceLocation Loc, Expr* LHS, Expr *RHS) { |
| Expr* LeftExprSansParen = LHS->IgnoreParenImpCasts(); |
| Expr* RightExprSansParen = RHS->IgnoreParenImpCasts(); |
| |
| // Special case: check for x == x (which is OK). |
| // Do not emit warnings for such cases. |
| if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(LeftExprSansParen)) |
| if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(RightExprSansParen)) |
| if (DRL->getDecl() == DRR->getDecl()) |
| return; |
| |
| |
| // Special case: check for comparisons against literals that can be exactly |
| // represented by APFloat. In such cases, do not emit a warning. This |
| // is a heuristic: often comparison against such literals are used to |
| // detect if a value in a variable has not changed. This clearly can |
| // lead to false negatives. |
| if (FloatingLiteral* FLL = dyn_cast<FloatingLiteral>(LeftExprSansParen)) { |
| if (FLL->isExact()) |
| return; |
| } else |
| if (FloatingLiteral* FLR = dyn_cast<FloatingLiteral>(RightExprSansParen)) |
| if (FLR->isExact()) |
| return; |
| |
| // Check for comparisons with builtin types. |
| if (CallExpr* CL = dyn_cast<CallExpr>(LeftExprSansParen)) |
| if (CL->isBuiltinCall()) |
| return; |
| |
| if (CallExpr* CR = dyn_cast<CallExpr>(RightExprSansParen)) |
| if (CR->isBuiltinCall()) |
| return; |
| |
| // Emit the diagnostic. |
| Diag(Loc, diag::warn_floatingpoint_eq) |
| << LHS->getSourceRange() << RHS->getSourceRange(); |
| } |
| |
| //===--- CHECK: Integer mixed-sign comparisons (-Wsign-compare) --------===// |
| //===--- CHECK: Lossy implicit conversions (-Wconversion) --------------===// |
| |
| namespace { |
| |
| /// Structure recording the 'active' range of an integer-valued |
| /// expression. |
| struct IntRange { |
| /// The number of bits active in the int. |
| unsigned Width; |
| |
| /// True if the int is known not to have negative values. |
| bool NonNegative; |
| |
| IntRange(unsigned Width, bool NonNegative) |
| : Width(Width), NonNegative(NonNegative) |
| {} |
| |
| /// Returns the range of the bool type. |
| static IntRange forBoolType() { |
| return IntRange(1, true); |
| } |
| |
| /// Returns the range of an opaque value of the given integral type. |
| static IntRange forValueOfType(ASTContext &C, QualType T) { |
| return forValueOfCanonicalType(C, |
| T->getCanonicalTypeInternal().getTypePtr()); |
| } |
| |
| /// Returns the range of an opaque value of a canonical integral type. |
| static IntRange forValueOfCanonicalType(ASTContext &C, const Type *T) { |
| assert(T->isCanonicalUnqualified()); |
| |
| if (const VectorType *VT = dyn_cast<VectorType>(T)) |
| T = VT->getElementType().getTypePtr(); |
| if (const ComplexType *CT = dyn_cast<ComplexType>(T)) |
| T = CT->getElementType().getTypePtr(); |
| |
| // For enum types, use the known bit width of the enumerators. |
| if (const EnumType *ET = dyn_cast<EnumType>(T)) { |
| EnumDecl *Enum = ET->getDecl(); |
| if (!Enum->isCompleteDefinition()) |
| return IntRange(C.getIntWidth(QualType(T, 0)), false); |
| |
| unsigned NumPositive = Enum->getNumPositiveBits(); |
| unsigned NumNegative = Enum->getNumNegativeBits(); |
| |
| return IntRange(std::max(NumPositive, NumNegative), NumNegative == 0); |
| } |
| |
| const BuiltinType *BT = cast<BuiltinType>(T); |
| assert(BT->isInteger()); |
| |
| return IntRange(C.getIntWidth(QualType(T, 0)), BT->isUnsignedInteger()); |
| } |
| |
| /// Returns the "target" range of a canonical integral type, i.e. |
| /// the range of values expressible in the type. |
| /// |
| /// This matches forValueOfCanonicalType except that enums have the |
| /// full range of their type, not the range of their enumerators. |
| static IntRange forTargetOfCanonicalType(ASTContext &C, const Type *T) { |
| assert(T->isCanonicalUnqualified()); |
| |
| if (const VectorType *VT = dyn_cast<VectorType>(T)) |
| T = VT->getElementType().getTypePtr(); |
| if (const ComplexType *CT = dyn_cast<ComplexType>(T)) |
| T = CT->getElementType().getTypePtr(); |
| if (const EnumType *ET = dyn_cast<EnumType>(T)) |
| T = C.getCanonicalType(ET->getDecl()->getIntegerType()).getTypePtr(); |
| |
| const BuiltinType *BT = cast<BuiltinType>(T); |
| assert(BT->isInteger()); |
| |
| return IntRange(C.getIntWidth(QualType(T, 0)), BT->isUnsignedInteger()); |
| } |
| |
| /// Returns the supremum of two ranges: i.e. their conservative merge. |
| static IntRange join(IntRange L, IntRange R) { |
| return IntRange(std::max(L.Width, R.Width), |
| L.NonNegative && R.NonNegative); |
| } |
| |
| /// Returns the infinum of two ranges: i.e. their aggressive merge. |
| static IntRange meet(IntRange L, IntRange R) { |
| return IntRange(std::min(L.Width, R.Width), |
| L.NonNegative || R.NonNegative); |
| } |
| }; |
| |
| static IntRange GetValueRange(ASTContext &C, llvm::APSInt &value, |
| unsigned MaxWidth) { |
| if (value.isSigned() && value.isNegative()) |
| return IntRange(value.getMinSignedBits(), false); |
| |
| if (value.getBitWidth() > MaxWidth) |
| value = value.trunc(MaxWidth); |
| |
| // isNonNegative() just checks the sign bit without considering |
| // signedness. |
| return IntRange(value.getActiveBits(), true); |
| } |
| |
| static IntRange GetValueRange(ASTContext &C, APValue &result, QualType Ty, |
| unsigned MaxWidth) { |
| if (result.isInt()) |
| return GetValueRange(C, result.getInt(), MaxWidth); |
| |
| if (result.isVector()) { |
| IntRange R = GetValueRange(C, result.getVectorElt(0), Ty, MaxWidth); |
| for (unsigned i = 1, e = result.getVectorLength(); i != e; ++i) { |
| IntRange El = GetValueRange(C, result.getVectorElt(i), Ty, MaxWidth); |
| R = IntRange::join(R, El); |
| } |
| return R; |
| } |
| |
| if (result.isComplexInt()) { |
| IntRange R = GetValueRange(C, result.getComplexIntReal(), MaxWidth); |
| IntRange I = GetValueRange(C, result.getComplexIntImag(), MaxWidth); |
| return IntRange::join(R, I); |
| } |
| |
| // This can happen with lossless casts to intptr_t of "based" lvalues. |
| // Assume it might use arbitrary bits. |
| // FIXME: The only reason we need to pass the type in here is to get |
| // the sign right on this one case. It would be nice if APValue |
| // preserved this. |
| assert(result.isLValue() || result.isAddrLabelDiff()); |
| return IntRange(MaxWidth, Ty->isUnsignedIntegerOrEnumerationType()); |
| } |
| |
| /// Pseudo-evaluate the given integer expression, estimating the |
| /// range of values it might take. |
| /// |
| /// \param MaxWidth - the width to which the value will be truncated |
| static IntRange GetExprRange(ASTContext &C, Expr *E, unsigned MaxWidth) { |
| E = E->IgnoreParens(); |
| |
| // Try a full evaluation first. |
| Expr::EvalResult result; |
| if (E->EvaluateAsRValue(result, C)) |
| return GetValueRange(C, result.Val, E->getType(), MaxWidth); |
| |
| // I think we only want to look through implicit casts here; if the |
| // user has an explicit widening cast, we should treat the value as |
| // being of the new, wider type. |
| if (ImplicitCastExpr *CE = dyn_cast<ImplicitCastExpr>(E)) { |
| if (CE->getCastKind() == CK_NoOp || CE->getCastKind() == CK_LValueToRValue) |
| return GetExprRange(C, CE->getSubExpr(), MaxWidth); |
| |
| IntRange OutputTypeRange = IntRange::forValueOfType(C, CE->getType()); |
| |
| bool isIntegerCast = (CE->getCastKind() == CK_IntegralCast); |
| |
| // Assume that non-integer casts can span the full range of the type. |
| if (!isIntegerCast) |
| return OutputTypeRange; |
| |
| IntRange SubRange |
| = GetExprRange(C, CE->getSubExpr(), |
| std::min(MaxWidth, OutputTypeRange.Width)); |
| |
| // Bail out if the subexpr's range is as wide as the cast type. |
| if (SubRange.Width >= OutputTypeRange.Width) |
| return OutputTypeRange; |
| |
| // Otherwise, we take the smaller width, and we're non-negative if |
| // either the output type or the subexpr is. |
| return IntRange(SubRange.Width, |
| SubRange.NonNegative || OutputTypeRange.NonNegative); |
| } |
| |
| if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) { |
| // If we can fold the condition, just take that operand. |
| bool CondResult; |
| if (CO->getCond()->EvaluateAsBooleanCondition(CondResult, C)) |
| return GetExprRange(C, CondResult ? CO->getTrueExpr() |
| : CO->getFalseExpr(), |
| MaxWidth); |
| |
| // Otherwise, conservatively merge. |
| IntRange L = GetExprRange(C, CO->getTrueExpr(), MaxWidth); |
| IntRange R = GetExprRange(C, CO->getFalseExpr(), MaxWidth); |
| return IntRange::join(L, R); |
| } |
| |
| if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) { |
| switch (BO->getOpcode()) { |
| |
| // Boolean-valued operations are single-bit and positive. |
| case BO_LAnd: |
| case BO_LOr: |
| case BO_LT: |
| case BO_GT: |
| case BO_LE: |
| case BO_GE: |
| case BO_EQ: |
| case BO_NE: |
| return IntRange::forBoolType(); |
| |
| // The type of the assignments is the type of the LHS, so the RHS |
| // is not necessarily the same type. |
| case BO_MulAssign: |
| case BO_DivAssign: |
| case BO_RemAssign: |
| case BO_AddAssign: |
| case BO_SubAssign: |
| case BO_XorAssign: |
| case BO_OrAssign: |
| // TODO: bitfields? |
| return IntRange::forValueOfType(C, E->getType()); |
| |
| // Simple assignments just pass through the RHS, which will have |
| // been coerced to the LHS type. |
| case BO_Assign: |
| // TODO: bitfields? |
| return GetExprRange(C, BO->getRHS(), MaxWidth); |
| |
| // Operations with opaque sources are black-listed. |
| case BO_PtrMemD: |
| case BO_PtrMemI: |
| return IntRange::forValueOfType(C, E->getType()); |
| |
| // Bitwise-and uses the *infinum* of the two source ranges. |
| case BO_And: |
| case BO_AndAssign: |
| return IntRange::meet(GetExprRange(C, BO->getLHS(), MaxWidth), |
| GetExprRange(C, BO->getRHS(), MaxWidth)); |
| |
| // Left shift gets black-listed based on a judgement call. |
| case BO_Shl: |
| // ...except that we want to treat '1 << (blah)' as logically |
| // positive. It's an important idiom. |
| if (IntegerLiteral *I |
| = dyn_cast<IntegerLiteral>(BO->getLHS()->IgnoreParenCasts())) { |
| if (I->getValue() == 1) { |
| IntRange R = IntRange::forValueOfType(C, E->getType()); |
| return IntRange(R.Width, /*NonNegative*/ true); |
| } |
| } |
| // fallthrough |
| |
| case BO_ShlAssign: |
| return IntRange::forValueOfType(C, E->getType()); |
| |
| // Right shift by a constant can narrow its left argument. |
| case BO_Shr: |
| case BO_ShrAssign: { |
| IntRange L = GetExprRange(C, BO->getLHS(), MaxWidth); |
| |
| // If the shift amount is a positive constant, drop the width by |
| // that much. |
| llvm::APSInt shift; |
| if (BO->getRHS()->isIntegerConstantExpr(shift, C) && |
| shift.isNonNegative()) { |
| unsigned zext = shift.getZExtValue(); |
| if (zext >= L.Width) |
| L.Width = (L.NonNegative ? 0 : 1); |
| else |
| L.Width -= zext; |
| } |
| |
| return L; |
| } |
| |
| // Comma acts as its right operand. |
| case BO_Comma: |
| return GetExprRange(C, BO->getRHS(), MaxWidth); |
| |
| // Black-list pointer subtractions. |
| case BO_Sub: |
| if (BO->getLHS()->getType()->isPointerType()) |
| return IntRange::forValueOfType(C, E->getType()); |
| break; |
| |
| // The width of a division result is mostly determined by the size |
| // of the LHS. |
| case BO_Div: { |
| // Don't 'pre-truncate' the operands. |
| unsigned opWidth = C.getIntWidth(E->getType()); |
| IntRange L = GetExprRange(C, BO->getLHS(), opWidth); |
| |
| // If the divisor is constant, use that. |
| llvm::APSInt divisor; |
| if (BO->getRHS()->isIntegerConstantExpr(divisor, C)) { |
| unsigned log2 = divisor.logBase2(); // floor(log_2(divisor)) |
| if (log2 >= L.Width) |
| L.Width = (L.NonNegative ? 0 : 1); |
| else |
| L.Width = std::min(L.Width - log2, MaxWidth); |
| return L; |
| } |
| |
| // Otherwise, just use the LHS's width. |
| IntRange R = GetExprRange(C, BO->getRHS(), opWidth); |
| return IntRange(L.Width, L.NonNegative && R.NonNegative); |
| } |
| |
| // The result of a remainder can't be larger than the result of |
| // either side. |
| case BO_Rem: { |
| // Don't 'pre-truncate' the operands. |
| unsigned opWidth = C.getIntWidth(E->getType()); |
| IntRange L = GetExprRange(C, BO->getLHS(), opWidth); |
| IntRange R = GetExprRange(C, BO->getRHS(), opWidth); |
| |
| IntRange meet = IntRange::meet(L, R); |
| meet.Width = std::min(meet.Width, MaxWidth); |
| return meet; |
| } |
| |
| // The default behavior is okay for these. |
| case BO_Mul: |
| case BO_Add: |
| case BO_Xor: |
| case BO_Or: |
| break; |
| } |
| |
| // The default case is to treat the operation as if it were closed |
| // on the narrowest type that encompasses both operands. |
| IntRange L = GetExprRange(C, BO->getLHS(), MaxWidth); |
| IntRange R = GetExprRange(C, BO->getRHS(), MaxWidth); |
| return IntRange::join(L, R); |
| } |
| |
| if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) { |
| switch (UO->getOpcode()) { |
| // Boolean-valued operations are white-listed. |
| case UO_LNot: |
| return IntRange::forBoolType(); |
| |
| // Operations with opaque sources are black-listed. |
| case UO_Deref: |
| case UO_AddrOf: // should be impossible |
| return IntRange::forValueOfType(C, E->getType()); |
| |
| default: |
| return GetExprRange(C, UO->getSubExpr(), MaxWidth); |
| } |
| } |
| |
| if (dyn_cast<OffsetOfExpr>(E)) { |
| IntRange::forValueOfType(C, E->getType()); |
| } |
| |
| if (FieldDecl *BitField = E->getBitField()) |
| return IntRange(BitField->getBitWidthValue(C), |
| BitField->getType()->isUnsignedIntegerOrEnumerationType()); |
| |
| return IntRange::forValueOfType(C, E->getType()); |
| } |
| |
| static IntRange GetExprRange(ASTContext &C, Expr *E) { |
| return GetExprRange(C, E, C.getIntWidth(E->getType())); |
| } |
| |
| /// Checks whether the given value, which currently has the given |
| /// source semantics, has the same value when coerced through the |
| /// target semantics. |
| static bool IsSameFloatAfterCast(const llvm::APFloat &value, |
| const llvm::fltSemantics &Src, |
| const llvm::fltSemantics &Tgt) { |
| llvm::APFloat truncated = value; |
| |
| bool ignored; |
| truncated.convert(Src, llvm::APFloat::rmNearestTiesToEven, &ignored); |
| truncated.convert(Tgt, llvm::APFloat::rmNearestTiesToEven, &ignored); |
| |
| return truncated.bitwiseIsEqual(value); |
| } |
| |
| /// Checks whether the given value, which currently has the given |
| /// source semantics, has the same value when coerced through the |
| /// target semantics. |
| /// |
| /// The value might be a vector of floats (or a complex number). |
| static bool IsSameFloatAfterCast(const APValue &value, |
| const llvm::fltSemantics &Src, |
| const llvm::fltSemantics &Tgt) { |
| if (value.isFloat()) |
| return IsSameFloatAfterCast(value.getFloat(), Src, Tgt); |
| |
| if (value.isVector()) { |
| for (unsigned i = 0, e = value.getVectorLength(); i != e; ++i) |
| if (!IsSameFloatAfterCast(value.getVectorElt(i), Src, Tgt)) |
| return false; |
| return true; |
| } |
| |
| assert(value.isComplexFloat()); |
| return (IsSameFloatAfterCast(value.getComplexFloatReal(), Src, Tgt) && |
| IsSameFloatAfterCast(value.getComplexFloatImag(), Src, Tgt)); |
| } |
| |
| static void AnalyzeImplicitConversions(Sema &S, Expr *E, SourceLocation CC); |
| |
| static bool IsZero(Sema &S, Expr *E) { |
| // Suppress cases where we are comparing against an enum constant. |
| if (const DeclRefExpr *DR = |
| dyn_cast<DeclRefExpr>(E->IgnoreParenImpCasts())) |
| if (isa<EnumConstantDecl>(DR->getDecl())) |
| return false; |
| |
| // Suppress cases where the '0' value is expanded from a macro. |
| if (E->getLocStart().isMacroID()) |
| return false; |
| |
| llvm::APSInt Value; |
| return E->isIntegerConstantExpr(Value, S.Context) && Value == 0; |
| } |
| |
| static bool HasEnumType(Expr *E) { |
| // Strip off implicit integral promotions. |
| while (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) { |
| if (ICE->getCastKind() != CK_IntegralCast && |
| ICE->getCastKind() != CK_NoOp) |
| break; |
| E = ICE->getSubExpr(); |
| } |
| |
| return E->getType()->isEnumeralType(); |
| } |
| |
| static void CheckTrivialUnsignedComparison(Sema &S, BinaryOperator *E) { |
| BinaryOperatorKind op = E->getOpcode(); |
| if (E->isValueDependent()) |
| return; |
| |
| if (op == BO_LT && IsZero(S, E->getRHS())) { |
| S.Diag(E->getOperatorLoc(), diag::warn_lunsigned_always_true_comparison) |
| << "< 0" << "false" << HasEnumType(E->getLHS()) |
| << E->getLHS()->getSourceRange() << E->getRHS()->getSourceRange(); |
| } else if (op == BO_GE && IsZero(S, E->getRHS())) { |
| S.Diag(E->getOperatorLoc(), diag::warn_lunsigned_always_true_comparison) |
| << ">= 0" << "true" << HasEnumType(E->getLHS()) |
| << E->getLHS()->getSourceRange() << E->getRHS()->getSourceRange(); |
| } else if (op == BO_GT && IsZero(S, E->getLHS())) { |
| S.Diag(E->getOperatorLoc(), diag::warn_runsigned_always_true_comparison) |
| << "0 >" << "false" << HasEnumType(E->getRHS()) |
| << E->getLHS()->getSourceRange() << E->getRHS()->getSourceRange(); |
| } else if (op == BO_LE && IsZero(S, E->getLHS())) { |
| S.Diag(E->getOperatorLoc(), diag::warn_runsigned_always_true_comparison) |
| << "0 <=" << "true" << HasEnumType(E->getRHS()) |
| << E->getLHS()->getSourceRange() << E->getRHS()->getSourceRange(); |
| } |
| } |
| |
| /// Analyze the operands of the given comparison. Implements the |
| /// fallback case from AnalyzeComparison. |
| static void AnalyzeImpConvsInComparison(Sema &S, BinaryOperator *E) { |
| AnalyzeImplicitConversions(S, E->getLHS(), E->getOperatorLoc()); |
| AnalyzeImplicitConversions(S, E->getRHS(), E->getOperatorLoc()); |
| } |
| |
| /// \brief Implements -Wsign-compare. |
| /// |
| /// \param E the binary operator to check for warnings |
| static void AnalyzeComparison(Sema &S, BinaryOperator *E) { |
| // The type the comparison is being performed in. |
| QualType T = E->getLHS()->getType(); |
| assert(S.Context.hasSameUnqualifiedType(T, E->getRHS()->getType()) |
| && "comparison with mismatched types"); |
| |
| // We don't do anything special if this isn't an unsigned integral |
| // comparison: we're only interested in integral comparisons, and |
| // signed comparisons only happen in cases we don't care to warn about. |
| // |
| // We also don't care about value-dependent expressions or expressions |
| // whose result is a constant. |
| if (!T->hasUnsignedIntegerRepresentation() |
| || E->isValueDependent() || E->isIntegerConstantExpr(S.Context)) |
| return AnalyzeImpConvsInComparison(S, E); |
| |
| Expr *LHS = E->getLHS()->IgnoreParenImpCasts(); |
| Expr *RHS = E->getRHS()->IgnoreParenImpCasts(); |
| |
| // Check to see if one of the (unmodified) operands is of different |
| // signedness. |
| Expr *signedOperand, *unsignedOperand; |
| if (LHS->getType()->hasSignedIntegerRepresentation()) { |
| assert(!RHS->getType()->hasSignedIntegerRepresentation() && |
| "unsigned comparison between two signed integer expressions?"); |
| signedOperand = LHS; |
| unsignedOperand = RHS; |
| } else if (RHS->getType()->hasSignedIntegerRepresentation()) { |
| signedOperand = RHS; |
| unsignedOperand = LHS; |
| } else { |
| CheckTrivialUnsignedComparison(S, E); |
| return AnalyzeImpConvsInComparison(S, E); |
| } |
| |
| // Otherwise, calculate the effective range of the signed operand. |
| IntRange signedRange = GetExprRange(S.Context, signedOperand); |
| |
| // Go ahead and analyze implicit conversions in the operands. Note |
| // that we skip the implicit conversions on both sides. |
| AnalyzeImplicitConversions(S, LHS, E->getOperatorLoc()); |
| AnalyzeImplicitConversions(S, RHS, E->getOperatorLoc()); |
| |
| // If the signed range is non-negative, -Wsign-compare won't fire, |
| // but we should still check for comparisons which are always true |
| // or false. |
| if (signedRange.NonNegative) |
| return CheckTrivialUnsignedComparison(S, E); |
| |
| // For (in)equality comparisons, if the unsigned operand is a |
| // constant which cannot collide with a overflowed signed operand, |
| // then reinterpreting the signed operand as unsigned will not |
| // change the result of the comparison. |
| if (E->isEqualityOp()) { |
| unsigned comparisonWidth = S.Context.getIntWidth(T); |
| IntRange unsignedRange = GetExprRange(S.Context, unsignedOperand); |
| |
| // We should never be unable to prove that the unsigned operand is |
| // non-negative. |
| assert(unsignedRange.NonNegative && "unsigned range includes negative?"); |
| |
| if (unsignedRange.Width < comparisonWidth) |
| return; |
| } |
| |
| S.DiagRuntimeBehavior(E->getOperatorLoc(), E, |
| S.PDiag(diag::warn_mixed_sign_comparison) |
| << LHS->getType() << RHS->getType() |
| << LHS->getSourceRange() << RHS->getSourceRange()); |
| } |
| |
| /// Analyzes an attempt to assign the given value to a bitfield. |
| /// |
| /// Returns true if there was something fishy about the attempt. |
| static bool AnalyzeBitFieldAssignment(Sema &S, FieldDecl *Bitfield, Expr *Init, |
| SourceLocation InitLoc) { |
| assert(Bitfield->isBitField()); |
| if (Bitfield->isInvalidDecl()) |
| return false; |
| |
| // White-list bool bitfields. |
| if (Bitfield->getType()->isBooleanType()) |
| return false; |
| |
| // Ignore value- or type-dependent expressions. |
| if (Bitfield->getBitWidth()->isValueDependent() || |
| Bitfield->getBitWidth()->isTypeDependent() || |
| Init->isValueDependent() || |
| Init->isTypeDependent()) |
| return false; |
| |
| Expr *OriginalInit = Init->IgnoreParenImpCasts(); |
| |
| llvm::APSInt Value; |
| if (!OriginalInit->EvaluateAsInt(Value, S.Context, Expr::SE_AllowSideEffects)) |
| return false; |
| |
| unsigned OriginalWidth = Value.getBitWidth(); |
| unsigned FieldWidth = Bitfield->getBitWidthValue(S.Context); |
| |
| if (OriginalWidth <= FieldWidth) |
| return false; |
| |
| // Compute the value which the bitfield will contain. |
| llvm::APSInt TruncatedValue = Value.trunc(FieldWidth); |
| TruncatedValue.setIsSigned(Bitfield->getType()->isSignedIntegerType()); |
| |
| // Check whether the stored value is equal to the original value. |
| TruncatedValue = TruncatedValue.extend(OriginalWidth); |
| if (llvm::APSInt::isSameValue(Value, TruncatedValue)) |
| return false; |
| |
| // Special-case bitfields of width 1: booleans are naturally 0/1, and |
| // therefore don't strictly fit into a signed bitfield of width 1. |
| if (FieldWidth == 1 && Value == 1) |
| return false; |
| |
| std::string PrettyValue = Value.toString(10); |
| std::string PrettyTrunc = TruncatedValue.toString(10); |
| |
| S.Diag(InitLoc, diag::warn_impcast_bitfield_precision_constant) |
| << PrettyValue << PrettyTrunc << OriginalInit->getType() |
| << Init->getSourceRange(); |
| |
| return true; |
| } |
| |
| /// Analyze the given simple or compound assignment for warning-worthy |
| /// operations. |
| static void AnalyzeAssignment(Sema &S, BinaryOperator *E) { |
| // Just recurse on the LHS. |
| AnalyzeImplicitConversions(S, E->getLHS(), E->getOperatorLoc()); |
| |
| // We want to recurse on the RHS as normal unless we're assigning to |
| // a bitfield. |
| if (FieldDecl *Bitfield = E->getLHS()->getBitField()) { |
| if (AnalyzeBitFieldAssignment(S, Bitfield, E->getRHS(), |
| E->getOperatorLoc())) { |
| // Recurse, ignoring any implicit conversions on the RHS. |
| return AnalyzeImplicitConversions(S, E->getRHS()->IgnoreParenImpCasts(), |
| E->getOperatorLoc()); |
| } |
| } |
| |
| AnalyzeImplicitConversions(S, E->getRHS(), E->getOperatorLoc()); |
| } |
| |
| /// Diagnose an implicit cast; purely a helper for CheckImplicitConversion. |
| static void DiagnoseImpCast(Sema &S, Expr *E, QualType SourceType, QualType T, |
| SourceLocation CContext, unsigned diag, |
| bool pruneControlFlow = false) { |
| if (pruneControlFlow) { |
| S.DiagRuntimeBehavior(E->getExprLoc(), E, |
| S.PDiag(diag) |
| << SourceType << T << E->getSourceRange() |
| << SourceRange(CContext)); |
| return; |
| } |
| S.Diag(E->getExprLoc(), diag) |
| << SourceType << T << E->getSourceRange() << SourceRange(CContext); |
| } |
| |
| /// Diagnose an implicit cast; purely a helper for CheckImplicitConversion. |
| static void DiagnoseImpCast(Sema &S, Expr *E, QualType T, |
| SourceLocation CContext, unsigned diag, |
| bool pruneControlFlow = false) { |
| DiagnoseImpCast(S, E, E->getType(), T, CContext, diag, pruneControlFlow); |
| } |
| |
| /// Diagnose an implicit cast from a literal expression. Does not warn when the |
| /// cast wouldn't lose information. |
| void DiagnoseFloatingLiteralImpCast(Sema &S, FloatingLiteral *FL, QualType T, |
| SourceLocation CContext) { |
| // Try to convert the literal exactly to an integer. If we can, don't warn. |
| bool isExact = false; |
| const llvm::APFloat &Value = FL->getValue(); |
| llvm::APSInt IntegerValue(S.Context.getIntWidth(T), |
| T->hasUnsignedIntegerRepresentation()); |
| if (Value.convertToInteger(IntegerValue, |
| llvm::APFloat::rmTowardZero, &isExact) |
| == llvm::APFloat::opOK && isExact) |
| return; |
| |
| SmallString<16> PrettySourceValue; |
| Value.toString(PrettySourceValue); |
| SmallString<16> PrettyTargetValue; |
| if (T->isSpecificBuiltinType(BuiltinType::Bool)) |
| PrettyTargetValue = IntegerValue == 0 ? "false" : "true"; |
| else |
| IntegerValue.toString(PrettyTargetValue); |
| |
| S.Diag(FL->getExprLoc(), diag::warn_impcast_literal_float_to_integer) |
| << FL->getType() << T.getUnqualifiedType() << PrettySourceValue |
| << PrettyTargetValue << FL->getSourceRange() << SourceRange(CContext); |
| } |
| |
| std::string PrettyPrintInRange(const llvm::APSInt &Value, IntRange Range) { |
| if (!Range.Width) return "0"; |
| |
| llvm::APSInt ValueInRange = Value; |
| ValueInRange.setIsSigned(!Range.NonNegative); |
| ValueInRange = ValueInRange.trunc(Range.Width); |
| return ValueInRange.toString(10); |
| } |
| |
| static bool IsImplicitBoolFloatConversion(Sema &S, Expr *Ex, bool ToBool) { |
| if (!isa<ImplicitCastExpr>(Ex)) |
| return false; |
| |
| Expr *InnerE = Ex->IgnoreParenImpCasts(); |
| const Type *Target = S.Context.getCanonicalType(Ex->getType()).getTypePtr(); |
| const Type *Source = |
| S.Context.getCanonicalType(InnerE->getType()).getTypePtr(); |
| if (Target->isDependentType()) |
| return false; |
| |
| const BuiltinType *FloatCandidateBT = |
| dyn_cast<BuiltinType>(ToBool ? Source : Target); |
| const Type *BoolCandidateType = ToBool ? Target : Source; |
| |
| return (BoolCandidateType->isSpecificBuiltinType(BuiltinType::Bool) && |
| FloatCandidateBT && (FloatCandidateBT->isFloatingPoint())); |
| } |
| |
| void CheckImplicitArgumentConversions(Sema &S, CallExpr *TheCall, |
| SourceLocation CC) { |
| unsigned NumArgs = TheCall->getNumArgs(); |
| for (unsigned i = 0; i < NumArgs; ++i) { |
| Expr *CurrA = TheCall->getArg(i); |
| if (!IsImplicitBoolFloatConversion(S, CurrA, true)) |
| continue; |
| |
| bool IsSwapped = ((i > 0) && |
| IsImplicitBoolFloatConversion(S, TheCall->getArg(i - 1), false)); |
| IsSwapped |= ((i < (NumArgs - 1)) && |
| IsImplicitBoolFloatConversion(S, TheCall->getArg(i + 1), false)); |
| if (IsSwapped) { |
| // Warn on this floating-point to bool conversion. |
| DiagnoseImpCast(S, CurrA->IgnoreParenImpCasts(), |
| CurrA->getType(), CC, |
| diag::warn_impcast_floating_point_to_bool); |
| } |
| } |
| } |
| |
| void CheckImplicitConversion(Sema &S, Expr *E, QualType T, |
| SourceLocation CC, bool *ICContext = 0) { |
| if (E->isTypeDependent() || E->isValueDependent()) return; |
| |
| const Type *Source = S.Context.getCanonicalType(E->getType()).getTypePtr(); |
| const Type *Target = S.Context.getCanonicalType(T).getTypePtr(); |
| if (Source == Target) return; |
| if (Target->isDependentType()) return; |
| |
| // If the conversion context location is invalid don't complain. We also |
| // don't want to emit a warning if the issue occurs from the expansion of |
| // a system macro. The problem is that 'getSpellingLoc()' is slow, so we |
| // delay this check as long as possible. Once we detect we are in that |
| // scenario, we just return. |
| if (CC.isInvalid()) |
| return; |
| |
| // Diagnose implicit casts to bool. |
| if (Target->isSpecificBuiltinType(BuiltinType::Bool)) { |
| if (isa<StringLiteral>(E)) |
| // Warn on string literal to bool. Checks for string literals in logical |
| // expressions, for instances, assert(0 && "error here"), is prevented |
| // by a check in AnalyzeImplicitConversions(). |
| return DiagnoseImpCast(S, E, T, CC, |
| diag::warn_impcast_string_literal_to_bool); |
| if (Source->isFunctionType()) { |
| // Warn on function to bool. Checks free functions and static member |
| // functions. Weakly imported functions are excluded from the check, |
| // since it's common to test their value to check whether the linker |
| // found a definition for them. |
| ValueDecl *D = 0; |
| if (DeclRefExpr* R = dyn_cast<DeclRefExpr>(E)) { |
| D = R->getDecl(); |
| } else if (MemberExpr *M = dyn_cast<MemberExpr>(E)) { |
| D = M->getMemberDecl(); |
| } |
| |
| if (D && !D->isWeak()) { |
| if (FunctionDecl* F = dyn_cast<FunctionDecl>(D)) { |
| S.Diag(E->getExprLoc(), diag::warn_impcast_function_to_bool) |
| << F << E->getSourceRange() << SourceRange(CC); |
| S.Diag(E->getExprLoc(), diag::note_function_to_bool_silence) |
| << FixItHint::CreateInsertion(E->getExprLoc(), "&"); |
| QualType ReturnType; |
| UnresolvedSet<4> NonTemplateOverloads; |
| S.isExprCallable(*E, ReturnType, NonTemplateOverloads); |
| if (!ReturnType.isNull() |
| && ReturnType->isSpecificBuiltinType(BuiltinType::Bool)) |
| S.Diag(E->getExprLoc(), diag::note_function_to_bool_call) |
| << FixItHint::CreateInsertion( |
| S.getPreprocessor().getLocForEndOfToken(E->getLocEnd()), "()"); |
| return; |
| } |
| } |
| } |
| } |
| |
| // Strip vector types. |
| if (isa<VectorType>(Source)) { |
| if (!isa<VectorType>(Target)) { |
| if (S.SourceMgr.isInSystemMacro(CC)) |
| return; |
| return DiagnoseImpCast(S, E, T, CC, diag::warn_impcast_vector_scalar); |
| } |
| |
| // If the vector cast is cast between two vectors of the same size, it is |
| // a bitcast, not a conversion. |
| if (S.Context.getTypeSize(Source) == S.Context.getTypeSize(Target)) |
| return; |
| |
| Source = cast<VectorType>(Source)->getElementType().getTypePtr(); |
| Target = cast<VectorType>(Target)->getElementType().getTypePtr(); |
| } |
| |
| // Strip complex types. |
| if (isa<ComplexType>(Source)) { |
| if (!isa<ComplexType>(Target)) { |
| if (S.SourceMgr.isInSystemMacro(CC)) |
| return; |
| |
| return DiagnoseImpCast(S, E, T, CC, diag::warn_impcast_complex_scalar); |
| } |
| |
| Source = cast<ComplexType>(Source)->getElementType().getTypePtr(); |
| Target = cast<ComplexType>(Target)->getElementType().getTypePtr(); |
| } |
| |
| const BuiltinType *SourceBT = dyn_cast<BuiltinType>(Source); |
| const BuiltinType *TargetBT = dyn_cast<BuiltinType>(Target); |
| |
| // If the source is floating point... |
| if (SourceBT && SourceBT->isFloatingPoint()) { |
| // ...and the target is floating point... |
| if (TargetBT && TargetBT->isFloatingPoint()) { |
| // ...then warn if we're dropping FP rank. |
| |
| // Builtin FP kinds are ordered by increasing FP rank. |
| if (SourceBT->getKind() > TargetBT->getKind()) { |
| // Don't warn about float constants that are precisely |
| // representable in the target type. |
| Expr::EvalResult result; |
| if (E->EvaluateAsRValue(result, S.Context)) { |
| // Value might be a float, a float vector, or a float complex. |
| if (IsSameFloatAfterCast(result.Val, |
| S.Context.getFloatTypeSemantics(QualType(TargetBT, 0)), |
| S.Context.getFloatTypeSemantics(QualType(SourceBT, 0)))) |
| return; |
| } |
| |
| if (S.SourceMgr.isInSystemMacro(CC)) |
| return; |
| |
| DiagnoseImpCast(S, E, T, CC, diag::warn_impcast_float_precision); |
| } |
| return; |
| } |
| |
| // If the target is integral, always warn. |
| if (TargetBT && TargetBT->isInteger()) { |
| if (S.SourceMgr.isInSystemMacro(CC)) |
| return; |
| |
| Expr *InnerE = E->IgnoreParenImpCasts(); |
| // We also want to warn on, e.g., "int i = -1.234" |
| if (UnaryOperator *UOp = dyn_cast<UnaryOperator>(InnerE)) |
| if (UOp->getOpcode() == UO_Minus || UOp->getOpcode() == UO_Plus) |
| InnerE = UOp->getSubExpr()->IgnoreParenImpCasts(); |
| |
| if (FloatingLiteral *FL = dyn_cast<FloatingLiteral>(InnerE)) { |
| DiagnoseFloatingLiteralImpCast(S, FL, T, CC); |
| } else { |
| DiagnoseImpCast(S, E, T, CC, diag::warn_impcast_float_integer); |
| } |
| } |
| |
| // If the target is bool, warn if expr is a function or method call. |
| if (Target->isSpecificBuiltinType(BuiltinType::Bool) && |
| isa<CallExpr>(E)) { |
| // Check last argument of function call to see if it is an |
| // implicit cast from a type matching the type the result |
| // is being cast to. |
| CallExpr *CEx = cast<CallExpr>(E); |
| unsigned NumArgs = CEx->getNumArgs(); |
| if (NumArgs > 0) { |
| Expr *LastA = CEx->getArg(NumArgs - 1); |
| Expr *InnerE = LastA->IgnoreParenImpCasts(); |
| const Type *InnerType = |
| S.Context.getCanonicalType(InnerE->getType()).getTypePtr(); |
| if (isa<ImplicitCastExpr>(LastA) && (InnerType == Target)) { |
| // Warn on this floating-point to bool conversion |
| DiagnoseImpCast(S, E, T, CC, |
| diag::warn_impcast_floating_point_to_bool); |
| } |
| } |
| } |
| return; |
| } |
| |
| if ((E->isNullPointerConstant(S.Context, Expr::NPC_ValueDependentIsNotNull) |
| == Expr::NPCK_GNUNull) && !Target->isAnyPointerType() |
| && !Target->isBlockPointerType() && !Target->isMemberPointerType()) { |
| SourceLocation Loc = E->getSourceRange().getBegin(); |
| if (Loc.isMacroID()) |
| Loc = S.SourceMgr.getImmediateExpansionRange(Loc).first; |
| if (!Loc.isMacroID() || CC.isMacroID()) |
| S.Diag(Loc, diag::warn_impcast_null_pointer_to_integer) |
| << T << clang::SourceRange(CC) |
| << FixItHint::CreateReplacement(Loc, S.getFixItZeroLiteralForType(T)); |
| } |
| |
| if (!Source->isIntegerType() || !Target->isIntegerType()) |
| return; |
| |
| // TODO: remove this early return once the false positives for constant->bool |
| // in templates, macros, etc, are reduced or removed. |
| if (Target->isSpecificBuiltinType(BuiltinType::Bool)) |
| return; |
| |
| IntRange SourceRange = GetExprRange(S.Context, E); |
| IntRange TargetRange = IntRange::forTargetOfCanonicalType(S.Context, Target); |
| |
| if (SourceRange.Width > TargetRange.Width) { |
| // If the source is a constant, use a default-on diagnostic. |
| // TODO: this should happen for bitfield stores, too. |
| llvm::APSInt Value(32); |
| if (E->isIntegerConstantExpr(Value, S.Context)) { |
| if (S.SourceMgr.isInSystemMacro(CC)) |
| return; |
| |
| std::string PrettySourceValue = Value.toString(10); |
| std::string PrettyTargetValue = PrettyPrintInRange(Value, TargetRange); |
| |
| S.DiagRuntimeBehavior(E->getExprLoc(), E, |
| S.PDiag(diag::warn_impcast_integer_precision_constant) |
| << PrettySourceValue << PrettyTargetValue |
| << E->getType() << T << E->getSourceRange() |
| << clang::SourceRange(CC)); |
| return; |
| } |
| |
| // People want to build with -Wshorten-64-to-32 and not -Wconversion. |
| if (S.SourceMgr.isInSystemMacro(CC)) |
| return; |
| |
| if (TargetRange.Width == 32 && S.Context.getIntWidth(E->getType()) == 64) |
| return DiagnoseImpCast(S, E, T, CC, diag::warn_impcast_integer_64_32, |
| /* pruneControlFlow */ true); |
| return DiagnoseImpCast(S, E, T, CC, diag::warn_impcast_integer_precision); |
| } |
| |
| if ((TargetRange.NonNegative && !SourceRange.NonNegative) || |
| (!TargetRange.NonNegative && SourceRange.NonNegative && |
| SourceRange.Width == TargetRange.Width)) { |
| |
| if (S.SourceMgr.isInSystemMacro(CC)) |
| return; |
| |
| unsigned DiagID = diag::warn_impcast_integer_sign; |
| |
| // Traditionally, gcc has warned about this under -Wsign-compare. |
| // We also want to warn about it in -Wconversion. |
| // So if -Wconversion is off, use a completely identical diagnostic |
| // in the sign-compare group. |
| // The conditional-checking code will |
| if (ICContext) { |
| DiagID = diag::warn_impcast_integer_sign_conditional; |
| *ICContext = true; |
| } |
| |
| return DiagnoseImpCast(S, E, T, CC, DiagID); |
| } |
| |
| // Diagnose conversions between different enumeration types. |
| // In C, we pretend that the type of an EnumConstantDecl is its enumeration |
| // type, to give us better diagnostics. |
| QualType SourceType = E->getType(); |
| if (!S.getLangOpts().CPlusPlus) { |
| if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) |
| if (EnumConstantDecl *ECD = dyn_cast<EnumConstantDecl>(DRE->getDecl())) { |
| EnumDecl *Enum = cast<EnumDecl>(ECD->getDeclContext()); |
| SourceType = S.Context.getTypeDeclType(Enum); |
| Source = S.Context.getCanonicalType(SourceType).getTypePtr(); |
| } |
| } |
| |
| if (const EnumType *SourceEnum = Source->getAs<EnumType>()) |
| if (const EnumType *TargetEnum = Target->getAs<EnumType>()) |
| if ((SourceEnum->getDecl()->getIdentifier() || |
| SourceEnum->getDecl()->getTypedefNameForAnonDecl()) && |
| (TargetEnum->getDecl()->getIdentifier() || |
| TargetEnum->getDecl()->getTypedefNameForAnonDecl()) && |
| SourceEnum != TargetEnum) { |
| if (S.SourceMgr.isInSystemMacro(CC)) |
| return; |
| |
| return DiagnoseImpCast(S, E, SourceType, T, CC, |
| diag::warn_impcast_different_enum_types); |
| } |
| |
| return; |
| } |
| |
| void CheckConditionalOperator(Sema &S, ConditionalOperator *E, |
| SourceLocation CC, QualType T); |
| |
| void CheckConditionalOperand(Sema &S, Expr *E, QualType T, |
| SourceLocation CC, bool &ICContext) { |
| E = E->IgnoreParenImpCasts(); |
| |
| if (isa<ConditionalOperator>(E)) |
| return CheckConditionalOperator(S, cast<ConditionalOperator>(E), CC, T); |
| |
| AnalyzeImplicitConversions(S, E, CC); |
| if (E->getType() != T) |
| return CheckImplicitConversion(S, E, T, CC, &ICContext); |
| return; |
| } |
| |
| void CheckConditionalOperator(Sema &S, ConditionalOperator *E, |
| SourceLocation CC, QualType T) { |
| AnalyzeImplicitConversions(S, E->getCond(), CC); |
| |
| bool Suspicious = false; |
| CheckConditionalOperand(S, E->getTrueExpr(), T, CC, Suspicious); |
| CheckConditionalOperand(S, E->getFalseExpr(), T, CC, Suspicious); |
| |
| // If -Wconversion would have warned about either of the candidates |
| // for a signedness conversion to the context type... |
| if (!Suspicious) return; |
| |
| // ...but it's currently ignored... |
| if (S.Diags.getDiagnosticLevel(diag::warn_impcast_integer_sign_conditional, |
| CC)) |
| return; |
| |
| // ...then check whether it would have warned about either of the |
| // candidates for a signedness conversion to the condition type. |
| if (E->getType() == T) return; |
| |
| Suspicious = false; |
| CheckImplicitConversion(S, E->getTrueExpr()->IgnoreParenImpCasts(), |
| E->getType(), CC, &Suspicious); |
| if (!Suspicious) |
| CheckImplicitConversion(S, E->getFalseExpr()->IgnoreParenImpCasts(), |
| E->getType(), CC, &Suspicious); |
| } |
| |
| /// AnalyzeImplicitConversions - Find and report any interesting |
| /// implicit conversions in the given expression. There are a couple |
| /// of competing diagnostics here, -Wconversion and -Wsign-compare. |
| void AnalyzeImplicitConversions(Sema &S, Expr *OrigE, SourceLocation CC) { |
| QualType T = OrigE->getType(); |
| Expr *E = OrigE->IgnoreParenImpCasts(); |
| |
| if (E->isTypeDependent() || E->isValueDependent()) |
| return; |
| |
| // For conditional operators, we analyze the arguments as if they |
| // were being fed directly into the output. |
| if (isa<ConditionalOperator>(E)) { |
| ConditionalOperator *CO = cast<ConditionalOperator>(E); |
| CheckConditionalOperator(S, CO, CC, T); |
| return; |
| } |
| |
| // Check implicit argument conversions for function calls. |
| if (CallExpr *Call = dyn_cast<CallExpr>(E)) |
| CheckImplicitArgumentConversions(S, Call, CC); |
| |
| // Go ahead and check any implicit conversions we might have skipped. |
| // The non-canonical typecheck is just an optimization; |
| // CheckImplicitConversion will filter out dead implicit conversions. |
| if (E->getType() != T) |
| CheckImplicitConversion(S, E, T, CC); |
| |
| // Now continue drilling into this expression. |
| |
| // Skip past explicit casts. |
| if (isa<ExplicitCastExpr>(E)) { |
| E = cast<ExplicitCastExpr>(E)->getSubExpr()->IgnoreParenImpCasts(); |
| return AnalyzeImplicitConversions(S, E, CC); |
| } |
| |
| if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) { |
| // Do a somewhat different check with comparison operators. |
| if (BO->isComparisonOp()) |
| return AnalyzeComparison(S, BO); |
| |
| // And with simple assignments. |
| if (BO->getOpcode() == BO_Assign) |
| return AnalyzeAssignment(S, BO); |
| } |
| |
| // These break the otherwise-useful invariant below. Fortunately, |
| // we don't really need to recurse into them, because any internal |
| // expressions should have been analyzed already when they were |
| // built into statements. |
| if (isa<StmtExpr>(E)) return; |
| |
| // Don't descend into unevaluated contexts. |
| if (isa<UnaryExprOrTypeTraitExpr>(E)) return; |
| |
| // Now just recurse over the expression's children. |
| CC = E->getExprLoc(); |
| BinaryOperator *BO = dyn_cast<BinaryOperator>(E); |
| bool IsLogicalOperator = BO && BO->isLogicalOp(); |
| for (Stmt::child_range I = E->children(); I; ++I) { |
| Expr *ChildExpr = dyn_cast_or_null<Expr>(*I); |
| if (!ChildExpr) |
| continue; |
| |
| if (IsLogicalOperator && |
| isa<StringLiteral>(ChildExpr->IgnoreParenImpCasts())) |
| // Ignore checking string literals that are in logical operators. |
| continue; |
| AnalyzeImplicitConversions(S, ChildExpr, CC); |
| } |
| } |
| |
| } // end anonymous namespace |
| |
| /// Diagnoses "dangerous" implicit conversions within the given |
| /// expression (which is a full expression). Implements -Wconversion |
| /// and -Wsign-compare. |
| /// |
| /// \param CC the "context" location of the implicit conversion, i.e. |
| /// the most location of the syntactic entity requiring the implicit |
| /// conversion |
| void Sema::CheckImplicitConversions(Expr *E, SourceLocation CC) { |
| // Don't diagnose in unevaluated contexts. |
| if (isUnevaluatedContext()) |
| return; |
| |
| // Don't diagnose for value- or type-dependent expressions. |
| if (E->isTypeDependent() || E->isValueDependent()) |
| return; |
| |
| // Check for array bounds violations in cases where the check isn't triggered |
| // elsewhere for other Expr types (like BinaryOperators), e.g. when an |
| // ArraySubscriptExpr is on the RHS of a variable initialization. |
| CheckArrayAccess(E); |
| |
| // This is not the right CC for (e.g.) a variable initialization. |
| AnalyzeImplicitConversions(*this, E, CC); |
| } |
| |
| void Sema::CheckBitFieldInitialization(SourceLocation InitLoc, |
| FieldDecl *BitField, |
| Expr *Init) { |
| (void) AnalyzeBitFieldAssignment(*this, BitField, Init, InitLoc); |
| } |
| |
| /// CheckParmsForFunctionDef - Check that the parameters of the given |
| /// function are appropriate for the definition of a function. This |
| /// takes care of any checks that cannot be performed on the |
| /// declaration itself, e.g., that the types of each of the function |
| /// parameters are complete. |
| bool Sema::CheckParmsForFunctionDef(ParmVarDecl **P, ParmVarDecl **PEnd, |
| bool CheckParameterNames) { |
| bool HasInvalidParm = false; |
| for (; P != PEnd; ++P) { |
| ParmVarDecl *Param = *P; |
| |
| // C99 6.7.5.3p4: the parameters in a parameter type list in a |
| // function declarator that is part of a function definition of |
| // that function shall not have incomplete type. |
| // |
| // This is also C++ [dcl.fct]p6. |
| if (!Param->isInvalidDecl() && |
| RequireCompleteType(Param->getLocation(), Param->getType(), |
| diag::err_typecheck_decl_incomplete_type)) { |
| Param->setInvalidDecl(); |
| HasInvalidParm = true; |
| } |
| |
| // C99 6.9.1p5: If the declarator includes a parameter type list, the |
| // declaration of each parameter shall include an identifier. |
| if (CheckParameterNames && |
| Param->getIdentifier() == 0 && |
| !Param->isImplicit() && |
| !getLangOpts().CPlusPlus) |
| Diag(Param->getLocation(), diag::err_parameter_name_omitted); |
| |
| // C99 6.7.5.3p12: |
| // If the function declarator is not part of a definition of that |
| // function, parameters may have incomplete type and may use the [*] |
| // notation in their sequences of declarator specifiers to specify |
| // variable length array types. |
| QualType PType = Param->getOriginalType(); |
| if (const ArrayType *AT = Context.getAsArrayType(PType)) { |
| if (AT->getSizeModifier() == ArrayType::Star) { |
| // FIXME: This diagnosic should point the '[*]' if source-location |
| // information is added for it. |
| Diag(Param->getLocation(), diag::err_array_star_in_function_definition); |
| } |
| } |
| } |
| |
| return HasInvalidParm; |
| } |
| |
| /// CheckCastAlign - Implements -Wcast-align, which warns when a |
| /// pointer cast increases the alignment requirements. |
| void Sema::CheckCastAlign(Expr *Op, QualType T, SourceRange TRange) { |
| // This is actually a lot of work to potentially be doing on every |
| // cast; don't do it if we're ignoring -Wcast_align (as is the default). |
| if (getDiagnostics().getDiagnosticLevel(diag::warn_cast_align, |
| TRange.getBegin()) |
| == DiagnosticsEngine::Ignored) |
| return; |
| |
| // Ignore dependent types. |
| if (T->isDependentType() || Op->getType()->isDependentType()) |
| return; |
| |
| // Require that the destination be a pointer type. |
| const PointerType *DestPtr = T->getAs<PointerType>(); |
| if (!DestPtr) return; |
| |
| // If the destination has alignment 1, we're done. |
| QualType DestPointee = DestPtr->getPointeeType(); |
| if (DestPointee->isIncompleteType()) return; |
| CharUnits DestAlign = Context.getTypeAlignInChars(DestPointee); |
| if (DestAlign.isOne()) return; |
| |
| // Require that the source be a pointer type. |
| const PointerType *SrcPtr = Op->getType()->getAs<PointerType>(); |
| if (!SrcPtr) return; |
| QualType SrcPointee = SrcPtr->getPointeeType(); |
| |
| // Whitelist casts from cv void*. We already implicitly |
| // whitelisted casts to cv void*, since they have alignment 1. |
| // Also whitelist casts involving incomplete types, which implicitly |
| // includes 'void'. |
| if (SrcPointee->isIncompleteType()) return; |
| |
| CharUnits SrcAlign = Context.getTypeAlignInChars(SrcPointee); |
| if (SrcAlign >= DestAlign) return; |
| |
| Diag(TRange.getBegin(), diag::warn_cast_align) |
| << Op->getType() << T |
| << static_cast<unsigned>(SrcAlign.getQuantity()) |
| << static_cast<unsigned>(DestAlign.getQuantity()) |
| << TRange << Op->getSourceRange(); |
| } |
| |
| static const Type* getElementType(const Expr *BaseExpr) { |
| const Type* EltType = BaseExpr->getType().getTypePtr(); |
| if (EltType->isAnyPointerType()) |
| return EltType->getPointeeType().getTypePtr(); |
| else if (EltType->isArrayType()) |
| return EltType->getBaseElementTypeUnsafe(); |
| return EltType; |
| } |
| |
| /// \brief Check whether this array fits the idiom of a size-one tail padded |
| /// array member of a struct. |
| /// |
| /// We avoid emitting out-of-bounds access warnings for such arrays as they are |
| /// commonly used to emulate flexible arrays in C89 code. |
| static bool IsTailPaddedMemberArray(Sema &S, llvm::APInt Size, |
| const NamedDecl *ND) { |
| if (Size != 1 || !ND) return false; |
| |
| const FieldDecl *FD = dyn_cast<FieldDecl>(ND); |
| if (!FD) return false; |
| |
| // Don't consider sizes resulting from macro expansions or template argument |
| // substitution to form C89 tail-padded arrays. |
| |
| TypeSourceInfo *TInfo = FD->getTypeSourceInfo(); |
| while (TInfo) { |
| TypeLoc TL = TInfo->getTypeLoc(); |
| // Look through typedefs. |
| const TypedefTypeLoc *TTL = dyn_cast<TypedefTypeLoc>(&TL); |
| if (TTL) { |
| const TypedefNameDecl *TDL = TTL->getTypedefNameDecl(); |
| TInfo = TDL->getTypeSourceInfo(); |
| continue; |
| } |
| ConstantArrayTypeLoc CTL = cast<ConstantArrayTypeLoc>(TL); |
| const Expr *SizeExpr = dyn_cast<IntegerLiteral>(CTL.getSizeExpr()); |
| if (!SizeExpr || SizeExpr->getExprLoc().isMacroID()) |
| return false; |
| break; |
| } |
| |
| const RecordDecl *RD = dyn_cast<RecordDecl>(FD->getDeclContext()); |
| if (!RD) return false; |
| if (RD->isUnion()) return false; |
| if (const CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) { |
| if (!CRD->isStandardLayout()) return false; |
| } |
| |
| // See if this is the last field decl in the record. |
| const Decl *D = FD; |
| while ((D = D->getNextDeclInContext())) |
| if (isa<FieldDecl>(D)) |
| return false; |
| return true; |
| } |
| |
| void Sema::CheckArrayAccess(const Expr *BaseExpr, const Expr *IndexExpr, |
| const ArraySubscriptExpr *ASE, |
| bool AllowOnePastEnd, bool IndexNegated) { |
| IndexExpr = IndexExpr->IgnoreParenImpCasts(); |
| if (IndexExpr->isValueDependent()) |
| return; |
| |
| const Type *EffectiveType = getElementType(BaseExpr); |
| BaseExpr = BaseExpr->IgnoreParenCasts(); |
| const ConstantArrayType *ArrayTy = |
| Context.getAsConstantArrayType(BaseExpr->getType()); |
| if (!ArrayTy) |
| return; |
| |
| llvm::APSInt index; |
| if (!IndexExpr->EvaluateAsInt(index, Context)) |
| return; |
| if (IndexNegated) |
| index = -index; |
| |
| const NamedDecl *ND = NULL; |
| if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(BaseExpr)) |
| ND = dyn_cast<NamedDecl>(DRE->getDecl()); |
| if (const MemberExpr *ME = dyn_cast<MemberExpr>(BaseExpr)) |
| ND = dyn_cast<NamedDecl>(ME->getMemberDecl()); |
| |
| if (index.isUnsigned() || !index.isNegative()) { |
| llvm::APInt size = ArrayTy->getSize(); |
| if (!size.isStrictlyPositive()) |
| return; |
| |
| const Type* BaseType = getElementType(BaseExpr); |
| if (BaseType != EffectiveType) { |
| // Make sure we're comparing apples to apples when comparing index to size |
| uint64_t ptrarith_typesize = Context.getTypeSize(EffectiveType); |
| uint64_t array_typesize = Context.getTypeSize(BaseType); |
| // Handle ptrarith_typesize being zero, such as when casting to void* |
| if (!ptrarith_typesize) ptrarith_typesize = 1; |
| if (ptrarith_typesize != array_typesize) { |
| // There's a cast to a different size type involved |
| uint64_t ratio = array_typesize / ptrarith_typesize; |
| // TODO: Be smarter about handling cases where array_typesize is not a |
| // multiple of ptrarith_typesize |
| if (ptrarith_typesize * ratio == array_typesize) |
| size *= llvm::APInt(size.getBitWidth(), ratio); |
| } |
| } |
| |
| if (size.getBitWidth() > index.getBitWidth()) |
| index = index.zext(size.getBitWidth()); |
| else if (size.getBitWidth() < index.getBitWidth()) |
| size = size.zext(index.getBitWidth()); |
| |
| // For array subscripting the index must be less than size, but for pointer |
| // arithmetic also allow the index (offset) to be equal to size since |
| // computing the next address after the end of the array is legal and |
| // commonly done e.g. in C++ iterators and range-based for loops. |
| if (AllowOnePastEnd ? index.ule(size) : index.ult(size)) |
| return; |
| |
| // Also don't warn for arrays of size 1 which are members of some |
| // structure. These are often used to approximate flexible arrays in C89 |
| // code. |
| if (IsTailPaddedMemberArray(*this, size, ND)) |
| return; |
| |
| // Suppress the warning if the subscript expression (as identified by the |
| // ']' location) and the index expression are both from macro expansions |
| // within a system header. |
| if (ASE) { |
| SourceLocation RBracketLoc = SourceMgr.getSpellingLoc( |
| ASE->getRBracketLoc()); |
| if (SourceMgr.isInSystemHeader(RBracketLoc)) { |
| SourceLocation IndexLoc = SourceMgr.getSpellingLoc( |
| IndexExpr->getLocStart()); |
| if (SourceMgr.isFromSameFile(RBracketLoc, IndexLoc)) |
| return; |
| } |
| } |
| |
| unsigned DiagID = diag::warn_ptr_arith_exceeds_bounds; |
| if (ASE) |
| DiagID = diag::warn_array_index_exceeds_bounds; |
| |
| DiagRuntimeBehavior(BaseExpr->getLocStart(), BaseExpr, |
| PDiag(DiagID) << index.toString(10, true) |
| << size.toString(10, true) |
| << (unsigned)size.getLimitedValue(~0U) |
| << IndexExpr->getSourceRange()); |
| } else { |
| unsigned DiagID = diag::warn_array_index_precedes_bounds; |
| if (!ASE) { |
| DiagID = diag::warn_ptr_arith_precedes_bounds; |
| if (index.isNegative()) index = -index; |
| } |
| |
| DiagRuntimeBehavior(BaseExpr->getLocStart(), BaseExpr, |
| PDiag(DiagID) << index.toString(10, true) |
| << IndexExpr->getSourceRange()); |
| } |
| |
| if (!ND) { |
| // Try harder to find a NamedDecl to point at in the note. |
| while (const ArraySubscriptExpr *ASE = |
| dyn_cast<ArraySubscriptExpr>(BaseExpr)) |
| BaseExpr = ASE->getBase()->IgnoreParenCasts(); |
| if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(BaseExpr)) |
| ND = dyn_cast<NamedDecl>(DRE->getDecl()); |
| if (const MemberExpr *ME = dyn_cast<MemberExpr>(BaseExpr)) |
| ND = dyn_cast<NamedDecl>(ME->getMemberDecl()); |
| } |
| |
| if (ND) |
| DiagRuntimeBehavior(ND->getLocStart(), BaseExpr, |
| PDiag(diag::note_array_index_out_of_bounds) |
| << ND->getDeclName()); |
| } |
| |
| void Sema::CheckArrayAccess(const Expr *expr) { |
| int AllowOnePastEnd = 0; |
| while (expr) { |
| expr = expr->IgnoreParenImpCasts(); |
| switch (expr->getStmtClass()) { |
| case Stmt::ArraySubscriptExprClass: { |
| const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(expr); |
| CheckArrayAccess(ASE->getBase(), ASE->getIdx(), ASE, |
| AllowOnePastEnd > 0); |
| return; |
| } |
| case Stmt::UnaryOperatorClass: { |
| // Only unwrap the * and & unary operators |
| const UnaryOperator *UO = cast<UnaryOperator>(expr); |
| expr = UO->getSubExpr(); |
| switch (UO->getOpcode()) { |
| case UO_AddrOf: |
| AllowOnePastEnd++; |
| break; |
| case UO_Deref: |
| AllowOnePastEnd--; |
| break; |
| default: |
| return; |
| } |
| break; |
| } |
| case Stmt::ConditionalOperatorClass: { |
| const ConditionalOperator *cond = cast<ConditionalOperator>(expr); |
| if (const Expr *lhs = cond->getLHS()) |
| CheckArrayAccess(lhs); |
| if (const Expr *rhs = cond->getRHS()) |
| CheckArrayAccess(rhs); |
| return; |
| } |
| default: |
| return; |
| } |
| } |
| } |
| |
| //===--- CHECK: Objective-C retain cycles ----------------------------------// |
| |
| namespace { |
| struct RetainCycleOwner { |
| RetainCycleOwner() : Variable(0), Indirect(false) {} |
| VarDecl *Variable; |
| SourceRange Range; |
| SourceLocation Loc; |
| bool Indirect; |
| |
| void setLocsFrom(Expr *e) { |
| Loc = e->getExprLoc(); |
| Range = e->getSourceRange(); |
| } |
| }; |
| } |
| |
| /// Consider whether capturing the given variable can possibly lead to |
| /// a retain cycle. |
| static bool considerVariable(VarDecl *var, Expr *ref, RetainCycleOwner &owner) { |
| // In ARC, it's captured strongly iff the variable has __strong |
| // lifetime. In MRR, it's captured strongly if the variable is |
| // __block and has an appropriate type. |
| if (var->getType().getObjCLifetime() != Qualifiers::OCL_Strong) |
| return false; |
| |
| owner.Variable = var; |
| owner.setLocsFrom(ref); |
| return true; |
| } |
| |
| static bool findRetainCycleOwner(Sema &S, Expr *e, RetainCycleOwner &owner) { |
| while (true) { |
| e = e->IgnoreParens(); |
| if (CastExpr *cast = dyn_cast<CastExpr>(e)) { |
| switch (cast->getCastKind()) { |
| case CK_BitCast: |
| case CK_LValueBitCast: |
| case CK_LValueToRValue: |
| case CK_ARCReclaimReturnedObject: |
| e = cast->getSubExpr(); |
| continue; |
| |
| default: |
| return false; |
| } |
| } |
| |
| if (ObjCIvarRefExpr *ref = dyn_cast<ObjCIvarRefExpr>(e)) { |
| ObjCIvarDecl *ivar = ref->getDecl(); |
| if (ivar->getType().getObjCLifetime() != Qualifiers::OCL_Strong) |
| return false; |
| |
| // Try to find a retain cycle in the base. |
| if (!findRetainCycleOwner(S, ref->getBase(), owner)) |
| return false; |
| |
| if (ref->isFreeIvar()) owner.setLocsFrom(ref); |
| owner.Indirect = true; |
| return true; |
| } |
| |
| if (DeclRefExpr *ref = dyn_cast<DeclRefExpr>(e)) { |
| VarDecl *var = dyn_cast<VarDecl>(ref->getDecl()); |
| if (!var) return false; |
| return considerVariable(var, ref, owner); |
| } |
| |
| if (MemberExpr *member = dyn_cast<MemberExpr>(e)) { |
| if (member->isArrow()) return false; |
| |
| // Don't count this as an indirect ownership. |
| e = member->getBase(); |
| continue; |
| } |
| |
| if (PseudoObjectExpr *pseudo = dyn_cast<PseudoObjectExpr>(e)) { |
| // Only pay attention to pseudo-objects on property references. |
| ObjCPropertyRefExpr *pre |
| = dyn_cast<ObjCPropertyRefExpr>(pseudo->getSyntacticForm() |
| ->IgnoreParens()); |
| if (!pre) return false; |
| if (pre->isImplicitProperty()) return false; |
| ObjCPropertyDecl *property = pre->getExplicitProperty(); |
| if (!property->isRetaining() && |
| !(property->getPropertyIvarDecl() && |
| property->getPropertyIvarDecl()->getType() |
| .getObjCLifetime() == Qualifiers::OCL_Strong)) |
| return false; |
| |
| owner.Indirect = true; |
| if (pre->isSuperReceiver()) { |
| owner.Variable = S.getCurMethodDecl()->getSelfDecl(); |
| if (!owner.Variable) |
| return false; |
| owner.Loc = pre->getLocation(); |
| owner.Range = pre->getSourceRange(); |
| return true; |
| } |
| e = const_cast<Expr*>(cast<OpaqueValueExpr>(pre->getBase()) |
| ->getSourceExpr()); |
| continue; |
| } |
| |
| // Array ivars? |
| |
| return false; |
| } |
| } |
| |
| namespace { |
| struct FindCaptureVisitor : EvaluatedExprVisitor<FindCaptureVisitor> { |
| FindCaptureVisitor(ASTContext &Context, VarDecl *variable) |
| : EvaluatedExprVisitor<FindCaptureVisitor>(Context), |
| Variable(variable), Capturer(0) {} |
| |
| VarDecl *Variable; |
| Expr *Capturer; |
| |
| void VisitDeclRefExpr(DeclRefExpr *ref) { |
| if (ref->getDecl() == Variable && !Capturer) |
| Capturer = ref; |
| } |
| |
| void VisitObjCIvarRefExpr(ObjCIvarRefExpr *ref) { |
| if (Capturer) return; |
| Visit(ref->getBase()); |
| if (Capturer && ref->isFreeIvar()) |
| Capturer = ref; |
| } |
| |
| void VisitBlockExpr(BlockExpr *block) { |
| // Look inside nested blocks |
| if (block->getBlockDecl()->capturesVariable(Variable)) |
| Visit(block->getBlockDecl()->getBody()); |
| } |
| |
| void VisitOpaqueValueExpr(OpaqueValueExpr *OVE) { |
| if (Capturer) return; |
| if (OVE->getSourceExpr()) |
| Visit(OVE->getSourceExpr()); |
| } |
| }; |
| } |
| |
| /// Check whether the given argument is a block which captures a |
| /// variable. |
| static Expr *findCapturingExpr(Sema &S, Expr *e, RetainCycleOwner &owner) { |
| assert(owner.Variable && owner.Loc.isValid()); |
| |
| e = e->IgnoreParenCasts(); |
| BlockExpr *block = dyn_cast<BlockExpr>(e); |
| if (!block || !block->getBlockDecl()->capturesVariable(owner.Variable)) |
| return 0; |
| |
| FindCaptureVisitor visitor(S.Context, owner.Variable); |
| visitor.Visit(block->getBlockDecl()->getBody()); |
| return visitor.Capturer; |
| } |
| |
| static void diagnoseRetainCycle(Sema &S, Expr *capturer, |
| RetainCycleOwner &owner) { |
| assert(capturer); |
| assert(owner.Variable && owner.Loc.isValid()); |
| |
| S.Diag(capturer->getExprLoc(), diag::warn_arc_retain_cycle) |
| << owner.Variable << capturer->getSourceRange(); |
| S.Diag(owner.Loc, diag::note_arc_retain_cycle_owner) |
| << owner.Indirect << owner.Range; |
| } |
| |
| /// Check for a keyword selector that starts with the word 'add' or |
| /// 'set'. |
| static bool isSetterLikeSelector(Selector sel) { |
| if (sel.isUnarySelector()) return false; |
| |
| StringRef str = sel.getNameForSlot(0); |
| while (!str.empty() && str.front() == '_') str = str.substr(1); |
| if (str.startswith("set")) |
| str = str.substr(3); |
| else if (str.startswith("add")) { |
| // Specially whitelist 'addOperationWithBlock:'. |
| if (sel.getNumArgs() == 1 && str.startswith("addOperationWithBlock")) |
| return false; |
| str = str.substr(3); |
| } |
| else |
| return false; |
| |
| if (str.empty()) return true; |
| return !islower(str.front()); |
| } |
| |
| /// Check a message send to see if it's likely to cause a retain cycle. |
| void Sema::checkRetainCycles(ObjCMessageExpr *msg) { |
| // Only check instance methods whose selector looks like a setter. |
| if (!msg->isInstanceMessage() || !isSetterLikeSelector(msg->getSelector())) |
| return; |
| |
| // Try to find a variable that the receiver is strongly owned by. |
| RetainCycleOwner owner; |
| if (msg->getReceiverKind() == ObjCMessageExpr::Instance) { |
| if (!findRetainCycleOwner(*this, msg->getInstanceReceiver(), owner)) |
| return; |
| } else { |
| assert(msg->getReceiverKind() == ObjCMessageExpr::SuperInstance); |
| owner.Variable = getCurMethodDecl()->getSelfDecl(); |
| owner.Loc = msg->getSuperLoc(); |
| owner.Range = msg->getSuperLoc(); |
| } |
| |
| // Check whether the receiver is captured by any of the arguments. |
| for (unsigned i = 0, e = msg->getNumArgs(); i != e; ++i) |
| if (Expr *capturer = findCapturingExpr(*this, msg->getArg(i), owner)) |
| return diagnoseRetainCycle(*this, capturer, owner); |
| } |
| |
| /// Check a property assign to see if it's likely to cause a retain cycle. |
| void Sema::checkRetainCycles(Expr *receiver, Expr *argument) { |
| RetainCycleOwner owner; |
| if (!findRetainCycleOwner(*this, receiver, owner)) |
| return; |
| |
| if (Expr *capturer = findCapturingExpr(*this, argument, owner)) |
| diagnoseRetainCycle(*this, capturer, owner); |
| } |
| |
| bool Sema::checkUnsafeAssigns(SourceLocation Loc, |
| QualType LHS, Expr *RHS) { |
| Qualifiers::ObjCLifetime LT = LHS.getObjCLifetime(); |
| if (LT != Qualifiers::OCL_Weak && LT != Qualifiers::OCL_ExplicitNone) |
| return false; |
| // strip off any implicit cast added to get to the one arc-specific |
| while (ImplicitCastExpr *cast = dyn_cast<ImplicitCastExpr>(RHS)) { |
| if (cast->getCastKind() == CK_ARCConsumeObject) { |
| Diag(Loc, diag::warn_arc_retained_assign) |
| << (LT == Qualifiers::OCL_ExplicitNone) << 1 |
| << RHS->getSourceRange(); |
| return true; |
| } |
| RHS = cast->getSubExpr(); |
| } |
| return false; |
| } |
| |
| void Sema::checkUnsafeExprAssigns(SourceLocation Loc, |
| Expr *LHS, Expr *RHS) { |
| QualType LHSType; |
| // PropertyRef on LHS type need be directly obtained from |
| // its declaration as it has a PsuedoType. |
| ObjCPropertyRefExpr *PRE |
| = dyn_cast<ObjCPropertyRefExpr>(LHS->IgnoreParens()); |
| if (PRE && !PRE->isImplicitProperty()) { |
| const ObjCPropertyDecl *PD = PRE->getExplicitProperty(); |
| if (PD) |
| LHSType = PD->getType(); |
| } |
| |
| if (LHSType.isNull()) |
| LHSType = LHS->getType(); |
| if (checkUnsafeAssigns(Loc, LHSType, RHS)) |
| return; |
| Qualifiers::ObjCLifetime LT = LHSType.getObjCLifetime(); |
| // FIXME. Check for other life times. |
| if (LT != Qualifiers::OCL_None) |
| return; |
| |
| if (PRE) { |
| if (PRE->isImplicitProperty()) |
| return; |
| const ObjCPropertyDecl *PD = PRE->getExplicitProperty(); |
| if (!PD) |
| return; |
| |
| unsigned Attributes = PD->getPropertyAttributes(); |
| if (Attributes & ObjCPropertyDecl::OBJC_PR_assign) { |
| // when 'assign' attribute was not explicitly specified |
| // by user, ignore it and rely on property type itself |
| // for lifetime info. |
| unsigned AsWrittenAttr = PD->getPropertyAttributesAsWritten(); |
| if (!(AsWrittenAttr & ObjCPropertyDecl::OBJC_PR_assign) && |
| LHSType->isObjCRetainableType()) |
| return; |
| |
| while (ImplicitCastExpr *cast = dyn_cast<ImplicitCastExpr>(RHS)) { |
| if (cast->getCastKind() == CK_ARCConsumeObject) { |
| Diag(Loc, diag::warn_arc_retained_property_assign) |
| << RHS->getSourceRange(); |
| return; |
| } |
| RHS = cast->getSubExpr(); |
| } |
| } |
| else if (Attributes & ObjCPropertyDecl::OBJC_PR_weak) { |
| while (ImplicitCastExpr *cast = dyn_cast<ImplicitCastExpr>(RHS)) { |
| if (cast->getCastKind() == CK_ARCConsumeObject) { |
| Diag(Loc, diag::warn_arc_retained_assign) |
| << 0 << 0<< RHS->getSourceRange(); |
| return; |
| } |
| RHS = cast->getSubExpr(); |
| } |
| } |
| } |
| } |
| |
| //===--- CHECK: Empty statement body (-Wempty-body) ---------------------===// |
| |
| namespace { |
| bool ShouldDiagnoseEmptyStmtBody(const SourceManager &SourceMgr, |
| SourceLocation StmtLoc, |
| const NullStmt *Body) { |
| // Do not warn if the body is a macro that expands to nothing, e.g: |
| // |
| // #define CALL(x) |
| // if (condition) |
| // CALL(0); |
| // |
| if (Body->hasLeadingEmptyMacro()) |
| return false; |
| |
| // Get line numbers of statement and body. |
| bool StmtLineInvalid; |
| unsigned StmtLine = SourceMgr.getSpellingLineNumber(StmtLoc, |
| &StmtLineInvalid); |
| if (StmtLineInvalid) |
| return false; |
| |
| bool BodyLineInvalid; |
| unsigned BodyLine = SourceMgr.getSpellingLineNumber(Body->getSemiLoc(), |
| &BodyLineInvalid); |
| if (BodyLineInvalid) |
| return false; |
| |
| // Warn if null statement and body are on the same line. |
| if (StmtLine != BodyLine) |
| return false; |
| |
| return true; |
| } |
| } // Unnamed namespace |
| |
| void Sema::DiagnoseEmptyStmtBody(SourceLocation StmtLoc, |
| const Stmt *Body, |
| unsigned DiagID) { |
| // Since this is a syntactic check, don't emit diagnostic for template |
| // instantiations, this just adds noise. |
| if (CurrentInstantiationScope) |
| return; |
| |
| // The body should be a null statement. |
| const NullStmt *NBody = dyn_cast<NullStmt>(Body); |
| if (!NBody) |
| return; |
| |
| // Do the usual checks. |
| if (!ShouldDiagnoseEmptyStmtBody(SourceMgr, StmtLoc, NBody)) |
| return; |
| |
| Diag(NBody->getSemiLoc(), DiagID); |
| Diag(NBody->getSemiLoc(), diag::note_empty_body_on_separate_line); |
| } |
| |
| void Sema::DiagnoseEmptyLoopBody(const Stmt *S, |
| const Stmt *PossibleBody) { |
| assert(!CurrentInstantiationScope); // Ensured by caller |
| |
| SourceLocation StmtLoc; |
| const Stmt *Body; |
| unsigned DiagID; |
| if (const ForStmt *FS = dyn_cast<ForStmt>(S)) { |
| StmtLoc = FS->getRParenLoc(); |
| Body = FS->getBody(); |
| DiagID = diag::warn_empty_for_body; |
| } else if (const WhileStmt *WS = dyn_cast<WhileStmt>(S)) { |
| StmtLoc = WS->getCond()->getSourceRange().getEnd(); |
| Body = WS->getBody(); |
| DiagID = diag::warn_empty_while_body; |
| } else |
| return; // Neither `for' nor `while'. |
| |
| // The body should be a null statement. |
| const NullStmt *NBody = dyn_cast<NullStmt>(Body); |
| if (!NBody) |
| return; |
| |
| // Skip expensive checks if diagnostic is disabled. |
| if (Diags.getDiagnosticLevel(DiagID, NBody->getSemiLoc()) == |
| DiagnosticsEngine::Ignored) |
| return; |
| |
| // Do the usual checks. |
| if (!ShouldDiagnoseEmptyStmtBody(SourceMgr, StmtLoc, NBody)) |
| return; |
| |
| // `for(...);' and `while(...);' are popular idioms, so in order to keep |
| // noise level low, emit diagnostics only if for/while is followed by a |
| // CompoundStmt, e.g.: |
| // for (int i = 0; i < n; i++); |
| // { |
| // a(i); |
| // } |
| // or if for/while is followed by a statement with more indentation |
| // than for/while itself: |
| // for (int i = 0; i < n; i++); |
| // a(i); |
| bool ProbableTypo = isa<CompoundStmt>(PossibleBody); |
| if (!ProbableTypo) { |
| bool BodyColInvalid; |
| unsigned BodyCol = SourceMgr.getPresumedColumnNumber( |
| PossibleBody->getLocStart(), |
| &BodyColInvalid); |
| if (BodyColInvalid) |
| return; |
| |
| bool StmtColInvalid; |
| unsigned StmtCol = SourceMgr.getPresumedColumnNumber( |
| S->getLocStart(), |
| &StmtColInvalid); |
| if (StmtColInvalid) |
| return; |
| |
| if (BodyCol > StmtCol) |
| ProbableTypo = true; |
| } |
| |
| if (ProbableTypo) { |
| Diag(NBody->getSemiLoc(), DiagID); |
| Diag(NBody->getSemiLoc(), diag::note_empty_body_on_separate_line); |
| } |
| } |
| |
| //===--- Layout compatibility ----------------------------------------------// |
| |
| namespace { |
| |
| bool isLayoutCompatible(ASTContext &C, QualType T1, QualType T2); |
| |
| /// \brief Check if two enumeration types are layout-compatible. |
| bool isLayoutCompatible(ASTContext &C, EnumDecl *ED1, EnumDecl *ED2) { |
| // C++11 [dcl.enum] p8: |
| // Two enumeration types are layout-compatible if they have the same |
| // underlying type. |
| return ED1->isComplete() && ED2->isComplete() && |
| C.hasSameType(ED1->getIntegerType(), ED2->getIntegerType()); |
| } |
| |
| /// \brief Check if two fields are layout-compatible. |
| bool isLayoutCompatible(ASTContext &C, FieldDecl *Field1, FieldDecl *Field2) { |
| if (!isLayoutCompatible(C, Field1->getType(), Field2->getType())) |
| return false; |
| |
| if (Field1->isBitField() != Field2->isBitField()) |
| return false; |
| |
| if (Field1->isBitField()) { |
| // Make sure that the bit-fields are the same length. |
| unsigned Bits1 = Field1->getBitWidthValue(C); |
| unsigned Bits2 = Field2->getBitWidthValue(C); |
| |
| if (Bits1 != Bits2) |
| return false; |
| } |
| |
| return true; |
| } |
| |
| /// \brief Check if two standard-layout structs are layout-compatible. |
| /// (C++11 [class.mem] p17) |
| bool isLayoutCompatibleStruct(ASTContext &C, |
| RecordDecl *RD1, |
| RecordDecl *RD2) { |
| // If both records are C++ classes, check that base classes match. |
| if (const CXXRecordDecl *D1CXX = dyn_cast<CXXRecordDecl>(RD1)) { |
| // If one of records is a CXXRecordDecl we are in C++ mode, |
| // thus the other one is a CXXRecordDecl, too. |
| const CXXRecordDecl *D2CXX = cast<CXXRecordDecl>(RD2); |
| // Check number of base classes. |
| if (D1CXX->getNumBases() != D2CXX->getNumBases()) |
| return false; |
| |
| // Check the base classes. |
| for (CXXRecordDecl::base_class_const_iterator |
| Base1 = D1CXX->bases_begin(), |
| BaseEnd1 = D1CXX->bases_end(), |
| Base2 = D2CXX->bases_begin(); |
| Base1 != BaseEnd1; |
| ++Base1, ++Base2) { |
| if (!isLayoutCompatible(C, Base1->getType(), Base2->getType())) |
| return false; |
| } |
| } else if (const CXXRecordDecl *D2CXX = dyn_cast<CXXRecordDecl>(RD2)) { |
| // If only RD2 is a C++ class, it should have zero base classes. |
| if (D2CXX->getNumBases() > 0) |
| return false; |
| } |
| |
| // Check the fields. |
| RecordDecl::field_iterator Field2 = RD2->field_begin(), |
| Field2End = RD2->field_end(), |
| Field1 = RD1->field_begin(), |
| Field1End = RD1->field_end(); |
| for ( ; Field1 != Field1End && Field2 != Field2End; ++Field1, ++Field2) { |
| if (!isLayoutCompatible(C, *Field1, *Field2)) |
| return false; |
| } |
| if (Field1 != Field1End || Field2 != Field2End) |
| return false; |
| |
| return true; |
| } |
| |
| /// \brief Check if two standard-layout unions are layout-compatible. |
| /// (C++11 [class.mem] p18) |
| bool isLayoutCompatibleUnion(ASTContext &C, |
| RecordDecl *RD1, |
| RecordDecl *RD2) { |
| llvm::SmallPtrSet<FieldDecl *, 8> UnmatchedFields; |
| for (RecordDecl::field_iterator Field2 = RD2->field_begin(), |
| Field2End = RD2->field_end(); |
| Field2 != Field2End; ++Field2) { |
| UnmatchedFields.insert(*Field2); |
| } |
| |
| for (RecordDecl::field_iterator Field1 = RD1->field_begin(), |
| Field1End = RD1->field_end(); |
| Field1 != Field1End; ++Field1) { |
| llvm::SmallPtrSet<FieldDecl *, 8>::iterator |
| I = UnmatchedFields.begin(), |
| E = UnmatchedFields.end(); |
| |
| for ( ; I != E; ++I) { |
| if (isLayoutCompatible(C, *Field1, *I)) { |
| bool Result = UnmatchedFields.erase(*I); |
| (void) Result; |
| assert(Result); |
| break; |
| } |
| } |
| if (I == E) |
| return false; |
| } |
| |
| return UnmatchedFields.empty(); |
| } |
| |
| bool isLayoutCompatible(ASTContext &C, RecordDecl *RD1, RecordDecl *RD2) { |
| if (RD1->isUnion() != RD2->isUnion()) |
| return false; |
| |
| if (RD1->isUnion()) |
| return isLayoutCompatibleUnion(C, RD1, RD2); |
| else |
| return isLayoutCompatibleStruct(C, RD1, RD2); |
| } |
| |
| /// \brief Check if two types are layout-compatible in C++11 sense. |
| bool isLayoutCompatible(ASTContext &C, QualType T1, QualType T2) { |
| if (T1.isNull() || T2.isNull()) |
| return false; |
| |
| // C++11 [basic.types] p11: |
| // If two types T1 and T2 are the same type, then T1 and T2 are |
| // layout-compatible types. |
| if (C.hasSameType(T1, T2)) |
| return true; |
| |
| T1 = T1.getCanonicalType().getUnqualifiedType(); |
| T2 = T2.getCanonicalType().getUnqualifiedType(); |
| |
| const Type::TypeClass TC1 = T1->getTypeClass(); |
| const Type::TypeClass TC2 = T2->getTypeClass(); |
| |
| if (TC1 != TC2) |
| return false; |
| |
| if (TC1 == Type::Enum) { |
| return isLayoutCompatible(C, |
| cast<EnumType>(T1)->getDecl(), |
| cast<EnumType>(T2)->getDecl()); |
| } else if (TC1 == Type::Record) { |
| if (!T1->isStandardLayoutType() || !T2->isStandardLayoutType()) |
| return false; |
| |
| return isLayoutCompatible(C, |
| cast<RecordType>(T1)->getDecl(), |
| cast<RecordType>(T2)->getDecl()); |
| } |
| |
| return false; |
| } |
| } |
| |
| //===--- CHECK: pointer_with_type_tag attribute: datatypes should match ----// |
| |
| namespace { |
| /// \brief Given a type tag expression find the type tag itself. |
| /// |
| /// \param TypeExpr Type tag expression, as it appears in user's code. |
| /// |
| /// \param VD Declaration of an identifier that appears in a type tag. |
| /// |
| /// \param MagicValue Type tag magic value. |
| bool FindTypeTagExpr(const Expr *TypeExpr, const ASTContext &Ctx, |
| const ValueDecl **VD, uint64_t *MagicValue) { |
| while(true) { |
| if (!TypeExpr) |
| return false; |
| |
| TypeExpr = TypeExpr->IgnoreParenImpCasts()->IgnoreParenCasts(); |
| |
| switch (TypeExpr->getStmtClass()) { |
| case Stmt::UnaryOperatorClass: { |
| const UnaryOperator *UO = cast<UnaryOperator>(TypeExpr); |
| if (UO->getOpcode() == UO_AddrOf || UO->getOpcode() == UO_Deref) { |
| TypeExpr = UO->getSubExpr(); |
| continue; |
| } |
| return false; |
| } |
| |
| case Stmt::DeclRefExprClass: { |
| const DeclRefExpr *DRE = cast<DeclRefExpr>(TypeExpr); |
| *VD = DRE->getDecl(); |
| return true; |
| } |
| |
| case Stmt::IntegerLiteralClass: { |
| const IntegerLiteral *IL = cast<IntegerLiteral>(TypeExpr); |
| llvm::APInt MagicValueAPInt = IL->getValue(); |
| if (MagicValueAPInt.getActiveBits() <= 64) { |
| *MagicValue = MagicValueAPInt.getZExtValue(); |
| return true; |
| } else |
| return false; |
| } |
| |
| case Stmt::BinaryConditionalOperatorClass: |
| case Stmt::ConditionalOperatorClass: { |
| const AbstractConditionalOperator *ACO = |
| cast<AbstractConditionalOperator>(TypeExpr); |
| bool Result; |
| if (ACO->getCond()->EvaluateAsBooleanCondition(Result, Ctx)) { |
| if (Result) |
| TypeExpr = ACO->getTrueExpr(); |
| else |
| TypeExpr = ACO->getFalseExpr(); |
| continue; |
| } |
| return false; |
| } |
| |
| case Stmt::BinaryOperatorClass: { |
| const BinaryOperator *BO = cast<BinaryOperator>(TypeExpr); |
| if (BO->getOpcode() == BO_Comma) { |
| TypeExpr = BO->getRHS(); |
| continue; |
| } |
| return false; |
| } |
| |
| default: |
| return false; |
| } |
| } |
| } |
| |
| /// \brief Retrieve the C type corresponding to type tag TypeExpr. |
| /// |
| /// \param TypeExpr Expression that specifies a type tag. |
| /// |
| /// \param MagicValues Registered magic values. |
| /// |
| /// \param FoundWrongKind Set to true if a type tag was found, but of a wrong |
| /// kind. |
| /// |
| /// \param TypeInfo Information about the corresponding C type. |
| /// |
| /// \returns true if the corresponding C type was found. |
| bool GetMatchingCType( |
| const IdentifierInfo *ArgumentKind, |
| const Expr *TypeExpr, const ASTContext &Ctx, |
| const llvm::DenseMap<Sema::TypeTagMagicValue, |
| Sema::TypeTagData> *MagicValues, |
| bool &FoundWrongKind, |
| Sema::TypeTagData &TypeInfo) { |
| FoundWrongKind = false; |
| |
| // Variable declaration that has type_tag_for_datatype attribute. |
| const ValueDecl *VD = NULL; |
| |
| uint64_t MagicValue; |
| |
| if (!FindTypeTagExpr(TypeExpr, Ctx, &VD, &MagicValue)) |
| return false; |
| |
| if (VD) { |
| for (specific_attr_iterator<TypeTagForDatatypeAttr> |
| I = VD->specific_attr_begin<TypeTagForDatatypeAttr>(), |
| E = VD->specific_attr_end<TypeTagForDatatypeAttr>(); |
| I != E; ++I) { |
| if (I->getArgumentKind() != ArgumentKind) { |
| FoundWrongKind = true; |
| return false; |
| } |
| TypeInfo.Type = I->getMatchingCType(); |
| TypeInfo.LayoutCompatible = I->getLayoutCompatible(); |
| TypeInfo.MustBeNull = I->getMustBeNull(); |
| return true; |
| } |
| return false; |
| } |
| |
| if (!MagicValues) |
| return false; |
| |
| llvm::DenseMap<Sema::TypeTagMagicValue, |
| Sema::TypeTagData>::const_iterator I = |
| MagicValues->find(std::make_pair(ArgumentKind, MagicValue)); |
| if (I == MagicValues->end()) |
| return false; |
| |
| TypeInfo = I->second; |
| return true; |
| } |
| } // unnamed namespace |
| |
| void Sema::RegisterTypeTagForDatatype(const IdentifierInfo *ArgumentKind, |
| uint64_t MagicValue, QualType Type, |
| bool LayoutCompatible, |
| bool MustBeNull) { |
| if (!TypeTagForDatatypeMagicValues) |
| TypeTagForDatatypeMagicValues.reset( |
| new llvm::DenseMap<TypeTagMagicValue, TypeTagData>); |
| |
| TypeTagMagicValue Magic(ArgumentKind, MagicValue); |
| (*TypeTagForDatatypeMagicValues)[Magic] = |
| TypeTagData(Type, LayoutCompatible, MustBeNull); |
| } |
| |
| namespace { |
| bool IsSameCharType(QualType T1, QualType T2) { |
| const BuiltinType *BT1 = T1->getAs<BuiltinType>(); |
| if (!BT1) |
| return false; |
| |
| const BuiltinType *BT2 = T2->getAs<BuiltinType>(); |
| if (!BT2) |
| return false; |
| |
| BuiltinType::Kind T1Kind = BT1->getKind(); |
| BuiltinType::Kind T2Kind = BT2->getKind(); |
| |
| return (T1Kind == BuiltinType::SChar && T2Kind == BuiltinType::Char_S) || |
| (T1Kind == BuiltinType::UChar && T2Kind == BuiltinType::Char_U) || |
| (T1Kind == BuiltinType::Char_U && T2Kind == BuiltinType::UChar) || |
| (T1Kind == BuiltinType::Char_S && T2Kind == BuiltinType::SChar); |
| } |
| } // unnamed namespace |
| |
| void Sema::CheckArgumentWithTypeTag(const ArgumentWithTypeTagAttr *Attr, |
| const Expr * const *ExprArgs) { |
| const IdentifierInfo *ArgumentKind = Attr->getArgumentKind(); |
| bool IsPointerAttr = Attr->getIsPointer(); |
| |
| const Expr *TypeTagExpr = ExprArgs[Attr->getTypeTagIdx()]; |
| bool FoundWrongKind; |
| TypeTagData TypeInfo; |
| if (!GetMatchingCType(ArgumentKind, TypeTagExpr, Context, |
| TypeTagForDatatypeMagicValues.get(), |
| FoundWrongKind, TypeInfo)) { |
| if (FoundWrongKind) |
| Diag(TypeTagExpr->getExprLoc(), |
| diag::warn_type_tag_for_datatype_wrong_kind) |
| << TypeTagExpr->getSourceRange(); |
| return; |
| } |
| |
| const Expr *ArgumentExpr = ExprArgs[Attr->getArgumentIdx()]; |
| if (IsPointerAttr) { |
| // Skip implicit cast of pointer to `void *' (as a function argument). |
| if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(ArgumentExpr)) |
| if (ICE->getType()->isVoidPointerType()) |
| ArgumentExpr = ICE->getSubExpr(); |
| } |
| QualType ArgumentType = ArgumentExpr->getType(); |
| |
| // Passing a `void*' pointer shouldn't trigger a warning. |
| if (IsPointerAttr && ArgumentType->isVoidPointerType()) |
| return; |
| |
| if (TypeInfo.MustBeNull) { |
| // Type tag with matching void type requires a null pointer. |
| if (!ArgumentExpr->isNullPointerConstant(Context, |
| Expr::NPC_ValueDependentIsNotNull)) { |
| Diag(ArgumentExpr->getExprLoc(), |
| diag::warn_type_safety_null_pointer_required) |
| << ArgumentKind->getName() |
| << ArgumentExpr->getSourceRange() |
| << TypeTagExpr->getSourceRange(); |
| } |
| return; |
| } |
| |
| QualType RequiredType = TypeInfo.Type; |
| if (IsPointerAttr) |
| RequiredType = Context.getPointerType(RequiredType); |
| |
| bool mismatch = false; |
| if (!TypeInfo.LayoutCompatible) { |
| mismatch = !Context.hasSameType(ArgumentType, RequiredType); |
| |
| // C++11 [basic.fundamental] p1: |
| // Plain char, signed char, and unsigned char are three distinct types. |
| // |
| // But we treat plain `char' as equivalent to `signed char' or `unsigned |
| // char' depending on the current char signedness mode. |
| if (mismatch) |
| if ((IsPointerAttr && IsSameCharType(ArgumentType->getPointeeType(), |
| RequiredType->getPointeeType())) || |
| (!IsPointerAttr && IsSameCharType(ArgumentType, RequiredType))) |
| mismatch = false; |
| } else |
| if (IsPointerAttr) |
| mismatch = !isLayoutCompatible(Context, |
| ArgumentType->getPointeeType(), |
| RequiredType->getPointeeType()); |
| else |
| mismatch = !isLayoutCompatible(Context, ArgumentType, RequiredType); |
| |
| if (mismatch) |
| Diag(ArgumentExpr->getExprLoc(), diag::warn_type_safety_type_mismatch) |
| << ArgumentType << ArgumentKind->getName() |
| << TypeInfo.LayoutCompatible << RequiredType |
| << ArgumentExpr->getSourceRange() |
| << TypeTagExpr->getSourceRange(); |
| } |
| |