| //===--- SemaStmt.cpp - Semantic Analysis for Statements ------------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements semantic analysis for statements. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "clang/Sema/SemaInternal.h" |
| #include "clang/AST/ASTContext.h" |
| #include "clang/AST/ASTDiagnostic.h" |
| #include "clang/AST/CharUnits.h" |
| #include "clang/AST/DeclObjC.h" |
| #include "clang/AST/EvaluatedExprVisitor.h" |
| #include "clang/AST/ExprCXX.h" |
| #include "clang/AST/ExprObjC.h" |
| #include "clang/AST/StmtCXX.h" |
| #include "clang/AST/StmtObjC.h" |
| #include "clang/AST/TypeLoc.h" |
| #include "clang/Lex/Preprocessor.h" |
| #include "clang/Sema/Initialization.h" |
| #include "clang/Sema/Lookup.h" |
| #include "clang/Sema/Scope.h" |
| #include "clang/Sema/ScopeInfo.h" |
| #include "llvm/ADT/ArrayRef.h" |
| #include "llvm/ADT/STLExtras.h" |
| #include "llvm/ADT/SmallPtrSet.h" |
| #include "llvm/ADT/SmallString.h" |
| #include "llvm/ADT/SmallVector.h" |
| using namespace clang; |
| using namespace sema; |
| |
| StmtResult Sema::ActOnExprStmt(ExprResult FE) { |
| if (FE.isInvalid()) |
| return StmtError(); |
| |
| FE = ActOnFinishFullExpr(FE.get(), FE.get()->getExprLoc(), |
| /*DiscardedValue*/ true); |
| if (FE.isInvalid()) |
| return StmtError(); |
| |
| // C99 6.8.3p2: The expression in an expression statement is evaluated as a |
| // void expression for its side effects. Conversion to void allows any |
| // operand, even incomplete types. |
| |
| // Same thing in for stmt first clause (when expr) and third clause. |
| return Owned(static_cast<Stmt*>(FE.take())); |
| } |
| |
| |
| StmtResult Sema::ActOnExprStmtError() { |
| DiscardCleanupsInEvaluationContext(); |
| return StmtError(); |
| } |
| |
| StmtResult Sema::ActOnNullStmt(SourceLocation SemiLoc, |
| bool HasLeadingEmptyMacro) { |
| return Owned(new (Context) NullStmt(SemiLoc, HasLeadingEmptyMacro)); |
| } |
| |
| StmtResult Sema::ActOnDeclStmt(DeclGroupPtrTy dg, SourceLocation StartLoc, |
| SourceLocation EndLoc) { |
| DeclGroupRef DG = dg.get(); |
| |
| // If we have an invalid decl, just return an error. |
| if (DG.isNull()) return StmtError(); |
| |
| return Owned(new (Context) DeclStmt(DG, StartLoc, EndLoc)); |
| } |
| |
| void Sema::ActOnForEachDeclStmt(DeclGroupPtrTy dg) { |
| DeclGroupRef DG = dg.get(); |
| |
| // If we don't have a declaration, or we have an invalid declaration, |
| // just return. |
| if (DG.isNull() || !DG.isSingleDecl()) |
| return; |
| |
| Decl *decl = DG.getSingleDecl(); |
| if (!decl || decl->isInvalidDecl()) |
| return; |
| |
| // Only variable declarations are permitted. |
| VarDecl *var = dyn_cast<VarDecl>(decl); |
| if (!var) { |
| Diag(decl->getLocation(), diag::err_non_variable_decl_in_for); |
| decl->setInvalidDecl(); |
| return; |
| } |
| |
| // foreach variables are never actually initialized in the way that |
| // the parser came up with. |
| var->setInit(0); |
| |
| // In ARC, we don't need to retain the iteration variable of a fast |
| // enumeration loop. Rather than actually trying to catch that |
| // during declaration processing, we remove the consequences here. |
| if (getLangOpts().ObjCAutoRefCount) { |
| QualType type = var->getType(); |
| |
| // Only do this if we inferred the lifetime. Inferred lifetime |
| // will show up as a local qualifier because explicit lifetime |
| // should have shown up as an AttributedType instead. |
| if (type.getLocalQualifiers().getObjCLifetime() == Qualifiers::OCL_Strong) { |
| // Add 'const' and mark the variable as pseudo-strong. |
| var->setType(type.withConst()); |
| var->setARCPseudoStrong(true); |
| } |
| } |
| } |
| |
| /// \brief Diagnose unused '==' and '!=' as likely typos for '=' or '|='. |
| /// |
| /// Adding a cast to void (or other expression wrappers) will prevent the |
| /// warning from firing. |
| static bool DiagnoseUnusedComparison(Sema &S, const Expr *E) { |
| SourceLocation Loc; |
| bool IsNotEqual, CanAssign; |
| |
| if (const BinaryOperator *Op = dyn_cast<BinaryOperator>(E)) { |
| if (Op->getOpcode() != BO_EQ && Op->getOpcode() != BO_NE) |
| return false; |
| |
| Loc = Op->getOperatorLoc(); |
| IsNotEqual = Op->getOpcode() == BO_NE; |
| CanAssign = Op->getLHS()->IgnoreParenImpCasts()->isLValue(); |
| } else if (const CXXOperatorCallExpr *Op = dyn_cast<CXXOperatorCallExpr>(E)) { |
| if (Op->getOperator() != OO_EqualEqual && |
| Op->getOperator() != OO_ExclaimEqual) |
| return false; |
| |
| Loc = Op->getOperatorLoc(); |
| IsNotEqual = Op->getOperator() == OO_ExclaimEqual; |
| CanAssign = Op->getArg(0)->IgnoreParenImpCasts()->isLValue(); |
| } else { |
| // Not a typo-prone comparison. |
| return false; |
| } |
| |
| // Suppress warnings when the operator, suspicious as it may be, comes from |
| // a macro expansion. |
| if (S.SourceMgr.isMacroBodyExpansion(Loc)) |
| return false; |
| |
| S.Diag(Loc, diag::warn_unused_comparison) |
| << (unsigned)IsNotEqual << E->getSourceRange(); |
| |
| // If the LHS is a plausible entity to assign to, provide a fixit hint to |
| // correct common typos. |
| if (CanAssign) { |
| if (IsNotEqual) |
| S.Diag(Loc, diag::note_inequality_comparison_to_or_assign) |
| << FixItHint::CreateReplacement(Loc, "|="); |
| else |
| S.Diag(Loc, diag::note_equality_comparison_to_assign) |
| << FixItHint::CreateReplacement(Loc, "="); |
| } |
| |
| return true; |
| } |
| |
| void Sema::DiagnoseUnusedExprResult(const Stmt *S) { |
| if (const LabelStmt *Label = dyn_cast_or_null<LabelStmt>(S)) |
| return DiagnoseUnusedExprResult(Label->getSubStmt()); |
| |
| const Expr *E = dyn_cast_or_null<Expr>(S); |
| if (!E) |
| return; |
| SourceLocation ExprLoc = E->IgnoreParens()->getExprLoc(); |
| // In most cases, we don't want to warn if the expression is written in a |
| // macro body, or if the macro comes from a system header. If the offending |
| // expression is a call to a function with the warn_unused_result attribute, |
| // we warn no matter the location. Because of the order in which the various |
| // checks need to happen, we factor out the macro-related test here. |
| bool ShouldSuppress = |
| SourceMgr.isMacroBodyExpansion(ExprLoc) || |
| SourceMgr.isInSystemMacro(ExprLoc); |
| |
| const Expr *WarnExpr; |
| SourceLocation Loc; |
| SourceRange R1, R2; |
| if (!E->isUnusedResultAWarning(WarnExpr, Loc, R1, R2, Context)) |
| return; |
| |
| // If this is a GNU statement expression expanded from a macro, it is probably |
| // unused because it is a function-like macro that can be used as either an |
| // expression or statement. Don't warn, because it is almost certainly a |
| // false positive. |
| if (isa<StmtExpr>(E) && Loc.isMacroID()) |
| return; |
| |
| // Okay, we have an unused result. Depending on what the base expression is, |
| // we might want to make a more specific diagnostic. Check for one of these |
| // cases now. |
| unsigned DiagID = diag::warn_unused_expr; |
| if (const ExprWithCleanups *Temps = dyn_cast<ExprWithCleanups>(E)) |
| E = Temps->getSubExpr(); |
| if (const CXXBindTemporaryExpr *TempExpr = dyn_cast<CXXBindTemporaryExpr>(E)) |
| E = TempExpr->getSubExpr(); |
| |
| if (DiagnoseUnusedComparison(*this, E)) |
| return; |
| |
| E = WarnExpr; |
| if (const CallExpr *CE = dyn_cast<CallExpr>(E)) { |
| if (E->getType()->isVoidType()) |
| return; |
| |
| // If the callee has attribute pure, const, or warn_unused_result, warn with |
| // a more specific message to make it clear what is happening. If the call |
| // is written in a macro body, only warn if it has the warn_unused_result |
| // attribute. |
| if (const Decl *FD = CE->getCalleeDecl()) { |
| if (FD->getAttr<WarnUnusedResultAttr>()) { |
| Diag(Loc, diag::warn_unused_result) << R1 << R2; |
| return; |
| } |
| if (ShouldSuppress) |
| return; |
| if (FD->getAttr<PureAttr>()) { |
| Diag(Loc, diag::warn_unused_call) << R1 << R2 << "pure"; |
| return; |
| } |
| if (FD->getAttr<ConstAttr>()) { |
| Diag(Loc, diag::warn_unused_call) << R1 << R2 << "const"; |
| return; |
| } |
| } |
| } else if (ShouldSuppress) |
| return; |
| |
| if (const ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(E)) { |
| if (getLangOpts().ObjCAutoRefCount && ME->isDelegateInitCall()) { |
| Diag(Loc, diag::err_arc_unused_init_message) << R1; |
| return; |
| } |
| const ObjCMethodDecl *MD = ME->getMethodDecl(); |
| if (MD && MD->getAttr<WarnUnusedResultAttr>()) { |
| Diag(Loc, diag::warn_unused_result) << R1 << R2; |
| return; |
| } |
| } else if (const PseudoObjectExpr *POE = dyn_cast<PseudoObjectExpr>(E)) { |
| const Expr *Source = POE->getSyntacticForm(); |
| if (isa<ObjCSubscriptRefExpr>(Source)) |
| DiagID = diag::warn_unused_container_subscript_expr; |
| else |
| DiagID = diag::warn_unused_property_expr; |
| } else if (const CXXFunctionalCastExpr *FC |
| = dyn_cast<CXXFunctionalCastExpr>(E)) { |
| if (isa<CXXConstructExpr>(FC->getSubExpr()) || |
| isa<CXXTemporaryObjectExpr>(FC->getSubExpr())) |
| return; |
| } |
| // Diagnose "(void*) blah" as a typo for "(void) blah". |
| else if (const CStyleCastExpr *CE = dyn_cast<CStyleCastExpr>(E)) { |
| TypeSourceInfo *TI = CE->getTypeInfoAsWritten(); |
| QualType T = TI->getType(); |
| |
| // We really do want to use the non-canonical type here. |
| if (T == Context.VoidPtrTy) { |
| PointerTypeLoc TL = TI->getTypeLoc().castAs<PointerTypeLoc>(); |
| |
| Diag(Loc, diag::warn_unused_voidptr) |
| << FixItHint::CreateRemoval(TL.getStarLoc()); |
| return; |
| } |
| } |
| |
| if (E->isGLValue() && E->getType().isVolatileQualified()) { |
| Diag(Loc, diag::warn_unused_volatile) << R1 << R2; |
| return; |
| } |
| |
| DiagRuntimeBehavior(Loc, 0, PDiag(DiagID) << R1 << R2); |
| } |
| |
| void Sema::ActOnStartOfCompoundStmt() { |
| PushCompoundScope(); |
| } |
| |
| void Sema::ActOnFinishOfCompoundStmt() { |
| PopCompoundScope(); |
| } |
| |
| sema::CompoundScopeInfo &Sema::getCurCompoundScope() const { |
| return getCurFunction()->CompoundScopes.back(); |
| } |
| |
| StmtResult Sema::ActOnCompoundStmt(SourceLocation L, SourceLocation R, |
| ArrayRef<Stmt *> Elts, bool isStmtExpr) { |
| const unsigned NumElts = Elts.size(); |
| |
| // If we're in C89 mode, check that we don't have any decls after stmts. If |
| // so, emit an extension diagnostic. |
| if (!getLangOpts().C99 && !getLangOpts().CPlusPlus) { |
| // Note that __extension__ can be around a decl. |
| unsigned i = 0; |
| // Skip over all declarations. |
| for (; i != NumElts && isa<DeclStmt>(Elts[i]); ++i) |
| /*empty*/; |
| |
| // We found the end of the list or a statement. Scan for another declstmt. |
| for (; i != NumElts && !isa<DeclStmt>(Elts[i]); ++i) |
| /*empty*/; |
| |
| if (i != NumElts) { |
| Decl *D = *cast<DeclStmt>(Elts[i])->decl_begin(); |
| Diag(D->getLocation(), diag::ext_mixed_decls_code); |
| } |
| } |
| // Warn about unused expressions in statements. |
| for (unsigned i = 0; i != NumElts; ++i) { |
| // Ignore statements that are last in a statement expression. |
| if (isStmtExpr && i == NumElts - 1) |
| continue; |
| |
| DiagnoseUnusedExprResult(Elts[i]); |
| } |
| |
| // Check for suspicious empty body (null statement) in `for' and `while' |
| // statements. Don't do anything for template instantiations, this just adds |
| // noise. |
| if (NumElts != 0 && !CurrentInstantiationScope && |
| getCurCompoundScope().HasEmptyLoopBodies) { |
| for (unsigned i = 0; i != NumElts - 1; ++i) |
| DiagnoseEmptyLoopBody(Elts[i], Elts[i + 1]); |
| } |
| |
| return Owned(new (Context) CompoundStmt(Context, Elts, L, R)); |
| } |
| |
| StmtResult |
| Sema::ActOnCaseStmt(SourceLocation CaseLoc, Expr *LHSVal, |
| SourceLocation DotDotDotLoc, Expr *RHSVal, |
| SourceLocation ColonLoc) { |
| assert((LHSVal != 0) && "missing expression in case statement"); |
| |
| if (getCurFunction()->SwitchStack.empty()) { |
| Diag(CaseLoc, diag::err_case_not_in_switch); |
| return StmtError(); |
| } |
| |
| if (!getLangOpts().CPlusPlus11) { |
| // C99 6.8.4.2p3: The expression shall be an integer constant. |
| // However, GCC allows any evaluatable integer expression. |
| if (!LHSVal->isTypeDependent() && !LHSVal->isValueDependent()) { |
| LHSVal = VerifyIntegerConstantExpression(LHSVal).take(); |
| if (!LHSVal) |
| return StmtError(); |
| } |
| |
| // GCC extension: The expression shall be an integer constant. |
| |
| if (RHSVal && !RHSVal->isTypeDependent() && !RHSVal->isValueDependent()) { |
| RHSVal = VerifyIntegerConstantExpression(RHSVal).take(); |
| // Recover from an error by just forgetting about it. |
| } |
| } |
| |
| LHSVal = ActOnFinishFullExpr(LHSVal, LHSVal->getExprLoc(), false, |
| getLangOpts().CPlusPlus11).take(); |
| if (RHSVal) |
| RHSVal = ActOnFinishFullExpr(RHSVal, RHSVal->getExprLoc(), false, |
| getLangOpts().CPlusPlus11).take(); |
| |
| CaseStmt *CS = new (Context) CaseStmt(LHSVal, RHSVal, CaseLoc, DotDotDotLoc, |
| ColonLoc); |
| getCurFunction()->SwitchStack.back()->addSwitchCase(CS); |
| return Owned(CS); |
| } |
| |
| /// ActOnCaseStmtBody - This installs a statement as the body of a case. |
| void Sema::ActOnCaseStmtBody(Stmt *caseStmt, Stmt *SubStmt) { |
| DiagnoseUnusedExprResult(SubStmt); |
| |
| CaseStmt *CS = static_cast<CaseStmt*>(caseStmt); |
| CS->setSubStmt(SubStmt); |
| } |
| |
| StmtResult |
| Sema::ActOnDefaultStmt(SourceLocation DefaultLoc, SourceLocation ColonLoc, |
| Stmt *SubStmt, Scope *CurScope) { |
| DiagnoseUnusedExprResult(SubStmt); |
| |
| if (getCurFunction()->SwitchStack.empty()) { |
| Diag(DefaultLoc, diag::err_default_not_in_switch); |
| return Owned(SubStmt); |
| } |
| |
| DefaultStmt *DS = new (Context) DefaultStmt(DefaultLoc, ColonLoc, SubStmt); |
| getCurFunction()->SwitchStack.back()->addSwitchCase(DS); |
| return Owned(DS); |
| } |
| |
| StmtResult |
| Sema::ActOnLabelStmt(SourceLocation IdentLoc, LabelDecl *TheDecl, |
| SourceLocation ColonLoc, Stmt *SubStmt) { |
| // If the label was multiply defined, reject it now. |
| if (TheDecl->getStmt()) { |
| Diag(IdentLoc, diag::err_redefinition_of_label) << TheDecl->getDeclName(); |
| Diag(TheDecl->getLocation(), diag::note_previous_definition); |
| return Owned(SubStmt); |
| } |
| |
| // Otherwise, things are good. Fill in the declaration and return it. |
| LabelStmt *LS = new (Context) LabelStmt(IdentLoc, TheDecl, SubStmt); |
| TheDecl->setStmt(LS); |
| if (!TheDecl->isGnuLocal()) { |
| TheDecl->setLocStart(IdentLoc); |
| TheDecl->setLocation(IdentLoc); |
| } |
| return Owned(LS); |
| } |
| |
| StmtResult Sema::ActOnAttributedStmt(SourceLocation AttrLoc, |
| ArrayRef<const Attr*> Attrs, |
| Stmt *SubStmt) { |
| // Fill in the declaration and return it. |
| AttributedStmt *LS = AttributedStmt::Create(Context, AttrLoc, Attrs, SubStmt); |
| return Owned(LS); |
| } |
| |
| StmtResult |
| Sema::ActOnIfStmt(SourceLocation IfLoc, FullExprArg CondVal, Decl *CondVar, |
| Stmt *thenStmt, SourceLocation ElseLoc, |
| Stmt *elseStmt) { |
| // If the condition was invalid, discard the if statement. We could recover |
| // better by replacing it with a valid expr, but don't do that yet. |
| if (!CondVal.get() && !CondVar) { |
| getCurFunction()->setHasDroppedStmt(); |
| return StmtError(); |
| } |
| |
| ExprResult CondResult(CondVal.release()); |
| |
| VarDecl *ConditionVar = 0; |
| if (CondVar) { |
| ConditionVar = cast<VarDecl>(CondVar); |
| CondResult = CheckConditionVariable(ConditionVar, IfLoc, true); |
| if (CondResult.isInvalid()) |
| return StmtError(); |
| } |
| Expr *ConditionExpr = CondResult.takeAs<Expr>(); |
| if (!ConditionExpr) |
| return StmtError(); |
| |
| DiagnoseUnusedExprResult(thenStmt); |
| |
| if (!elseStmt) { |
| DiagnoseEmptyStmtBody(ConditionExpr->getLocEnd(), thenStmt, |
| diag::warn_empty_if_body); |
| } |
| |
| DiagnoseUnusedExprResult(elseStmt); |
| |
| return Owned(new (Context) IfStmt(Context, IfLoc, ConditionVar, ConditionExpr, |
| thenStmt, ElseLoc, elseStmt)); |
| } |
| |
| /// ConvertIntegerToTypeWarnOnOverflow - Convert the specified APInt to have |
| /// the specified width and sign. If an overflow occurs, detect it and emit |
| /// the specified diagnostic. |
| void Sema::ConvertIntegerToTypeWarnOnOverflow(llvm::APSInt &Val, |
| unsigned NewWidth, bool NewSign, |
| SourceLocation Loc, |
| unsigned DiagID) { |
| // Perform a conversion to the promoted condition type if needed. |
| if (NewWidth > Val.getBitWidth()) { |
| // If this is an extension, just do it. |
| Val = Val.extend(NewWidth); |
| Val.setIsSigned(NewSign); |
| |
| // If the input was signed and negative and the output is |
| // unsigned, don't bother to warn: this is implementation-defined |
| // behavior. |
| // FIXME: Introduce a second, default-ignored warning for this case? |
| } else if (NewWidth < Val.getBitWidth()) { |
| // If this is a truncation, check for overflow. |
| llvm::APSInt ConvVal(Val); |
| ConvVal = ConvVal.trunc(NewWidth); |
| ConvVal.setIsSigned(NewSign); |
| ConvVal = ConvVal.extend(Val.getBitWidth()); |
| ConvVal.setIsSigned(Val.isSigned()); |
| if (ConvVal != Val) |
| Diag(Loc, DiagID) << Val.toString(10) << ConvVal.toString(10); |
| |
| // Regardless of whether a diagnostic was emitted, really do the |
| // truncation. |
| Val = Val.trunc(NewWidth); |
| Val.setIsSigned(NewSign); |
| } else if (NewSign != Val.isSigned()) { |
| // Convert the sign to match the sign of the condition. This can cause |
| // overflow as well: unsigned(INTMIN) |
| // We don't diagnose this overflow, because it is implementation-defined |
| // behavior. |
| // FIXME: Introduce a second, default-ignored warning for this case? |
| llvm::APSInt OldVal(Val); |
| Val.setIsSigned(NewSign); |
| } |
| } |
| |
| namespace { |
| struct CaseCompareFunctor { |
| bool operator()(const std::pair<llvm::APSInt, CaseStmt*> &LHS, |
| const llvm::APSInt &RHS) { |
| return LHS.first < RHS; |
| } |
| bool operator()(const std::pair<llvm::APSInt, CaseStmt*> &LHS, |
| const std::pair<llvm::APSInt, CaseStmt*> &RHS) { |
| return LHS.first < RHS.first; |
| } |
| bool operator()(const llvm::APSInt &LHS, |
| const std::pair<llvm::APSInt, CaseStmt*> &RHS) { |
| return LHS < RHS.first; |
| } |
| }; |
| } |
| |
| /// CmpCaseVals - Comparison predicate for sorting case values. |
| /// |
| static bool CmpCaseVals(const std::pair<llvm::APSInt, CaseStmt*>& lhs, |
| const std::pair<llvm::APSInt, CaseStmt*>& rhs) { |
| if (lhs.first < rhs.first) |
| return true; |
| |
| if (lhs.first == rhs.first && |
| lhs.second->getCaseLoc().getRawEncoding() |
| < rhs.second->getCaseLoc().getRawEncoding()) |
| return true; |
| return false; |
| } |
| |
| /// CmpEnumVals - Comparison predicate for sorting enumeration values. |
| /// |
| static bool CmpEnumVals(const std::pair<llvm::APSInt, EnumConstantDecl*>& lhs, |
| const std::pair<llvm::APSInt, EnumConstantDecl*>& rhs) |
| { |
| return lhs.first < rhs.first; |
| } |
| |
| /// EqEnumVals - Comparison preficate for uniqing enumeration values. |
| /// |
| static bool EqEnumVals(const std::pair<llvm::APSInt, EnumConstantDecl*>& lhs, |
| const std::pair<llvm::APSInt, EnumConstantDecl*>& rhs) |
| { |
| return lhs.first == rhs.first; |
| } |
| |
| /// GetTypeBeforeIntegralPromotion - Returns the pre-promotion type of |
| /// potentially integral-promoted expression @p expr. |
| static QualType GetTypeBeforeIntegralPromotion(Expr *&expr) { |
| if (ExprWithCleanups *cleanups = dyn_cast<ExprWithCleanups>(expr)) |
| expr = cleanups->getSubExpr(); |
| while (ImplicitCastExpr *impcast = dyn_cast<ImplicitCastExpr>(expr)) { |
| if (impcast->getCastKind() != CK_IntegralCast) break; |
| expr = impcast->getSubExpr(); |
| } |
| return expr->getType(); |
| } |
| |
| StmtResult |
| Sema::ActOnStartOfSwitchStmt(SourceLocation SwitchLoc, Expr *Cond, |
| Decl *CondVar) { |
| ExprResult CondResult; |
| |
| VarDecl *ConditionVar = 0; |
| if (CondVar) { |
| ConditionVar = cast<VarDecl>(CondVar); |
| CondResult = CheckConditionVariable(ConditionVar, SourceLocation(), false); |
| if (CondResult.isInvalid()) |
| return StmtError(); |
| |
| Cond = CondResult.release(); |
| } |
| |
| if (!Cond) |
| return StmtError(); |
| |
| class SwitchConvertDiagnoser : public ICEConvertDiagnoser { |
| Expr *Cond; |
| |
| public: |
| SwitchConvertDiagnoser(Expr *Cond) |
| : ICEConvertDiagnoser(/*AllowScopedEnumerations*/true, false, true), |
| Cond(Cond) {} |
| |
| virtual SemaDiagnosticBuilder diagnoseNotInt(Sema &S, SourceLocation Loc, |
| QualType T) { |
| return S.Diag(Loc, diag::err_typecheck_statement_requires_integer) << T; |
| } |
| |
| virtual SemaDiagnosticBuilder diagnoseIncomplete( |
| Sema &S, SourceLocation Loc, QualType T) { |
| return S.Diag(Loc, diag::err_switch_incomplete_class_type) |
| << T << Cond->getSourceRange(); |
| } |
| |
| virtual SemaDiagnosticBuilder diagnoseExplicitConv( |
| Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) { |
| return S.Diag(Loc, diag::err_switch_explicit_conversion) << T << ConvTy; |
| } |
| |
| virtual SemaDiagnosticBuilder noteExplicitConv( |
| Sema &S, CXXConversionDecl *Conv, QualType ConvTy) { |
| return S.Diag(Conv->getLocation(), diag::note_switch_conversion) |
| << ConvTy->isEnumeralType() << ConvTy; |
| } |
| |
| virtual SemaDiagnosticBuilder diagnoseAmbiguous(Sema &S, SourceLocation Loc, |
| QualType T) { |
| return S.Diag(Loc, diag::err_switch_multiple_conversions) << T; |
| } |
| |
| virtual SemaDiagnosticBuilder noteAmbiguous( |
| Sema &S, CXXConversionDecl *Conv, QualType ConvTy) { |
| return S.Diag(Conv->getLocation(), diag::note_switch_conversion) |
| << ConvTy->isEnumeralType() << ConvTy; |
| } |
| |
| virtual SemaDiagnosticBuilder diagnoseConversion( |
| Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) { |
| llvm_unreachable("conversion functions are permitted"); |
| } |
| } SwitchDiagnoser(Cond); |
| |
| CondResult = |
| PerformContextualImplicitConversion(SwitchLoc, Cond, SwitchDiagnoser); |
| if (CondResult.isInvalid()) return StmtError(); |
| Cond = CondResult.take(); |
| |
| // C99 6.8.4.2p5 - Integer promotions are performed on the controlling expr. |
| CondResult = UsualUnaryConversions(Cond); |
| if (CondResult.isInvalid()) return StmtError(); |
| Cond = CondResult.take(); |
| |
| if (!CondVar) { |
| CondResult = ActOnFinishFullExpr(Cond, SwitchLoc); |
| if (CondResult.isInvalid()) |
| return StmtError(); |
| Cond = CondResult.take(); |
| } |
| |
| getCurFunction()->setHasBranchIntoScope(); |
| |
| SwitchStmt *SS = new (Context) SwitchStmt(Context, ConditionVar, Cond); |
| getCurFunction()->SwitchStack.push_back(SS); |
| return Owned(SS); |
| } |
| |
| static void AdjustAPSInt(llvm::APSInt &Val, unsigned BitWidth, bool IsSigned) { |
| if (Val.getBitWidth() < BitWidth) |
| Val = Val.extend(BitWidth); |
| else if (Val.getBitWidth() > BitWidth) |
| Val = Val.trunc(BitWidth); |
| Val.setIsSigned(IsSigned); |
| } |
| |
| StmtResult |
| Sema::ActOnFinishSwitchStmt(SourceLocation SwitchLoc, Stmt *Switch, |
| Stmt *BodyStmt) { |
| SwitchStmt *SS = cast<SwitchStmt>(Switch); |
| assert(SS == getCurFunction()->SwitchStack.back() && |
| "switch stack missing push/pop!"); |
| |
| SS->setBody(BodyStmt, SwitchLoc); |
| getCurFunction()->SwitchStack.pop_back(); |
| |
| Expr *CondExpr = SS->getCond(); |
| if (!CondExpr) return StmtError(); |
| |
| QualType CondType = CondExpr->getType(); |
| |
| Expr *CondExprBeforePromotion = CondExpr; |
| QualType CondTypeBeforePromotion = |
| GetTypeBeforeIntegralPromotion(CondExprBeforePromotion); |
| |
| // C++ 6.4.2.p2: |
| // Integral promotions are performed (on the switch condition). |
| // |
| // A case value unrepresentable by the original switch condition |
| // type (before the promotion) doesn't make sense, even when it can |
| // be represented by the promoted type. Therefore we need to find |
| // the pre-promotion type of the switch condition. |
| if (!CondExpr->isTypeDependent()) { |
| // We have already converted the expression to an integral or enumeration |
| // type, when we started the switch statement. If we don't have an |
| // appropriate type now, just return an error. |
| if (!CondType->isIntegralOrEnumerationType()) |
| return StmtError(); |
| |
| if (CondExpr->isKnownToHaveBooleanValue()) { |
| // switch(bool_expr) {...} is often a programmer error, e.g. |
| // switch(n && mask) { ... } // Doh - should be "n & mask". |
| // One can always use an if statement instead of switch(bool_expr). |
| Diag(SwitchLoc, diag::warn_bool_switch_condition) |
| << CondExpr->getSourceRange(); |
| } |
| } |
| |
| // Get the bitwidth of the switched-on value before promotions. We must |
| // convert the integer case values to this width before comparison. |
| bool HasDependentValue |
| = CondExpr->isTypeDependent() || CondExpr->isValueDependent(); |
| unsigned CondWidth |
| = HasDependentValue ? 0 : Context.getIntWidth(CondTypeBeforePromotion); |
| bool CondIsSigned |
| = CondTypeBeforePromotion->isSignedIntegerOrEnumerationType(); |
| |
| // Accumulate all of the case values in a vector so that we can sort them |
| // and detect duplicates. This vector contains the APInt for the case after |
| // it has been converted to the condition type. |
| typedef SmallVector<std::pair<llvm::APSInt, CaseStmt*>, 64> CaseValsTy; |
| CaseValsTy CaseVals; |
| |
| // Keep track of any GNU case ranges we see. The APSInt is the low value. |
| typedef std::vector<std::pair<llvm::APSInt, CaseStmt*> > CaseRangesTy; |
| CaseRangesTy CaseRanges; |
| |
| DefaultStmt *TheDefaultStmt = 0; |
| |
| bool CaseListIsErroneous = false; |
| |
| for (SwitchCase *SC = SS->getSwitchCaseList(); SC && !HasDependentValue; |
| SC = SC->getNextSwitchCase()) { |
| |
| if (DefaultStmt *DS = dyn_cast<DefaultStmt>(SC)) { |
| if (TheDefaultStmt) { |
| Diag(DS->getDefaultLoc(), diag::err_multiple_default_labels_defined); |
| Diag(TheDefaultStmt->getDefaultLoc(), diag::note_duplicate_case_prev); |
| |
| // FIXME: Remove the default statement from the switch block so that |
| // we'll return a valid AST. This requires recursing down the AST and |
| // finding it, not something we are set up to do right now. For now, |
| // just lop the entire switch stmt out of the AST. |
| CaseListIsErroneous = true; |
| } |
| TheDefaultStmt = DS; |
| |
| } else { |
| CaseStmt *CS = cast<CaseStmt>(SC); |
| |
| Expr *Lo = CS->getLHS(); |
| |
| if (Lo->isTypeDependent() || Lo->isValueDependent()) { |
| HasDependentValue = true; |
| break; |
| } |
| |
| llvm::APSInt LoVal; |
| |
| if (getLangOpts().CPlusPlus11) { |
| // C++11 [stmt.switch]p2: the constant-expression shall be a converted |
| // constant expression of the promoted type of the switch condition. |
| ExprResult ConvLo = |
| CheckConvertedConstantExpression(Lo, CondType, LoVal, CCEK_CaseValue); |
| if (ConvLo.isInvalid()) { |
| CaseListIsErroneous = true; |
| continue; |
| } |
| Lo = ConvLo.take(); |
| } else { |
| // We already verified that the expression has a i-c-e value (C99 |
| // 6.8.4.2p3) - get that value now. |
| LoVal = Lo->EvaluateKnownConstInt(Context); |
| |
| // If the LHS is not the same type as the condition, insert an implicit |
| // cast. |
| Lo = DefaultLvalueConversion(Lo).take(); |
| Lo = ImpCastExprToType(Lo, CondType, CK_IntegralCast).take(); |
| } |
| |
| // Convert the value to the same width/sign as the condition had prior to |
| // integral promotions. |
| // |
| // FIXME: This causes us to reject valid code: |
| // switch ((char)c) { case 256: case 0: return 0; } |
| // Here we claim there is a duplicated condition value, but there is not. |
| ConvertIntegerToTypeWarnOnOverflow(LoVal, CondWidth, CondIsSigned, |
| Lo->getLocStart(), |
| diag::warn_case_value_overflow); |
| |
| CS->setLHS(Lo); |
| |
| // If this is a case range, remember it in CaseRanges, otherwise CaseVals. |
| if (CS->getRHS()) { |
| if (CS->getRHS()->isTypeDependent() || |
| CS->getRHS()->isValueDependent()) { |
| HasDependentValue = true; |
| break; |
| } |
| CaseRanges.push_back(std::make_pair(LoVal, CS)); |
| } else |
| CaseVals.push_back(std::make_pair(LoVal, CS)); |
| } |
| } |
| |
| if (!HasDependentValue) { |
| // If we don't have a default statement, check whether the |
| // condition is constant. |
| llvm::APSInt ConstantCondValue; |
| bool HasConstantCond = false; |
| if (!HasDependentValue && !TheDefaultStmt) { |
| HasConstantCond |
| = CondExprBeforePromotion->EvaluateAsInt(ConstantCondValue, Context, |
| Expr::SE_AllowSideEffects); |
| assert(!HasConstantCond || |
| (ConstantCondValue.getBitWidth() == CondWidth && |
| ConstantCondValue.isSigned() == CondIsSigned)); |
| } |
| bool ShouldCheckConstantCond = HasConstantCond; |
| |
| // Sort all the scalar case values so we can easily detect duplicates. |
| std::stable_sort(CaseVals.begin(), CaseVals.end(), CmpCaseVals); |
| |
| if (!CaseVals.empty()) { |
| for (unsigned i = 0, e = CaseVals.size(); i != e; ++i) { |
| if (ShouldCheckConstantCond && |
| CaseVals[i].first == ConstantCondValue) |
| ShouldCheckConstantCond = false; |
| |
| if (i != 0 && CaseVals[i].first == CaseVals[i-1].first) { |
| // If we have a duplicate, report it. |
| // First, determine if either case value has a name |
| StringRef PrevString, CurrString; |
| Expr *PrevCase = CaseVals[i-1].second->getLHS()->IgnoreParenCasts(); |
| Expr *CurrCase = CaseVals[i].second->getLHS()->IgnoreParenCasts(); |
| if (DeclRefExpr *DeclRef = dyn_cast<DeclRefExpr>(PrevCase)) { |
| PrevString = DeclRef->getDecl()->getName(); |
| } |
| if (DeclRefExpr *DeclRef = dyn_cast<DeclRefExpr>(CurrCase)) { |
| CurrString = DeclRef->getDecl()->getName(); |
| } |
| SmallString<16> CaseValStr; |
| CaseVals[i-1].first.toString(CaseValStr); |
| |
| if (PrevString == CurrString) |
| Diag(CaseVals[i].second->getLHS()->getLocStart(), |
| diag::err_duplicate_case) << |
| (PrevString.empty() ? CaseValStr.str() : PrevString); |
| else |
| Diag(CaseVals[i].second->getLHS()->getLocStart(), |
| diag::err_duplicate_case_differing_expr) << |
| (PrevString.empty() ? CaseValStr.str() : PrevString) << |
| (CurrString.empty() ? CaseValStr.str() : CurrString) << |
| CaseValStr; |
| |
| Diag(CaseVals[i-1].second->getLHS()->getLocStart(), |
| diag::note_duplicate_case_prev); |
| // FIXME: We really want to remove the bogus case stmt from the |
| // substmt, but we have no way to do this right now. |
| CaseListIsErroneous = true; |
| } |
| } |
| } |
| |
| // Detect duplicate case ranges, which usually don't exist at all in |
| // the first place. |
| if (!CaseRanges.empty()) { |
| // Sort all the case ranges by their low value so we can easily detect |
| // overlaps between ranges. |
| std::stable_sort(CaseRanges.begin(), CaseRanges.end()); |
| |
| // Scan the ranges, computing the high values and removing empty ranges. |
| std::vector<llvm::APSInt> HiVals; |
| for (unsigned i = 0, e = CaseRanges.size(); i != e; ++i) { |
| llvm::APSInt &LoVal = CaseRanges[i].first; |
| CaseStmt *CR = CaseRanges[i].second; |
| Expr *Hi = CR->getRHS(); |
| llvm::APSInt HiVal; |
| |
| if (getLangOpts().CPlusPlus11) { |
| // C++11 [stmt.switch]p2: the constant-expression shall be a converted |
| // constant expression of the promoted type of the switch condition. |
| ExprResult ConvHi = |
| CheckConvertedConstantExpression(Hi, CondType, HiVal, |
| CCEK_CaseValue); |
| if (ConvHi.isInvalid()) { |
| CaseListIsErroneous = true; |
| continue; |
| } |
| Hi = ConvHi.take(); |
| } else { |
| HiVal = Hi->EvaluateKnownConstInt(Context); |
| |
| // If the RHS is not the same type as the condition, insert an |
| // implicit cast. |
| Hi = DefaultLvalueConversion(Hi).take(); |
| Hi = ImpCastExprToType(Hi, CondType, CK_IntegralCast).take(); |
| } |
| |
| // Convert the value to the same width/sign as the condition. |
| ConvertIntegerToTypeWarnOnOverflow(HiVal, CondWidth, CondIsSigned, |
| Hi->getLocStart(), |
| diag::warn_case_value_overflow); |
| |
| CR->setRHS(Hi); |
| |
| // If the low value is bigger than the high value, the case is empty. |
| if (LoVal > HiVal) { |
| Diag(CR->getLHS()->getLocStart(), diag::warn_case_empty_range) |
| << SourceRange(CR->getLHS()->getLocStart(), |
| Hi->getLocEnd()); |
| CaseRanges.erase(CaseRanges.begin()+i); |
| --i, --e; |
| continue; |
| } |
| |
| if (ShouldCheckConstantCond && |
| LoVal <= ConstantCondValue && |
| ConstantCondValue <= HiVal) |
| ShouldCheckConstantCond = false; |
| |
| HiVals.push_back(HiVal); |
| } |
| |
| // Rescan the ranges, looking for overlap with singleton values and other |
| // ranges. Since the range list is sorted, we only need to compare case |
| // ranges with their neighbors. |
| for (unsigned i = 0, e = CaseRanges.size(); i != e; ++i) { |
| llvm::APSInt &CRLo = CaseRanges[i].first; |
| llvm::APSInt &CRHi = HiVals[i]; |
| CaseStmt *CR = CaseRanges[i].second; |
| |
| // Check to see whether the case range overlaps with any |
| // singleton cases. |
| CaseStmt *OverlapStmt = 0; |
| llvm::APSInt OverlapVal(32); |
| |
| // Find the smallest value >= the lower bound. If I is in the |
| // case range, then we have overlap. |
| CaseValsTy::iterator I = std::lower_bound(CaseVals.begin(), |
| CaseVals.end(), CRLo, |
| CaseCompareFunctor()); |
| if (I != CaseVals.end() && I->first < CRHi) { |
| OverlapVal = I->first; // Found overlap with scalar. |
| OverlapStmt = I->second; |
| } |
| |
| // Find the smallest value bigger than the upper bound. |
| I = std::upper_bound(I, CaseVals.end(), CRHi, CaseCompareFunctor()); |
| if (I != CaseVals.begin() && (I-1)->first >= CRLo) { |
| OverlapVal = (I-1)->first; // Found overlap with scalar. |
| OverlapStmt = (I-1)->second; |
| } |
| |
| // Check to see if this case stmt overlaps with the subsequent |
| // case range. |
| if (i && CRLo <= HiVals[i-1]) { |
| OverlapVal = HiVals[i-1]; // Found overlap with range. |
| OverlapStmt = CaseRanges[i-1].second; |
| } |
| |
| if (OverlapStmt) { |
| // If we have a duplicate, report it. |
| Diag(CR->getLHS()->getLocStart(), diag::err_duplicate_case) |
| << OverlapVal.toString(10); |
| Diag(OverlapStmt->getLHS()->getLocStart(), |
| diag::note_duplicate_case_prev); |
| // FIXME: We really want to remove the bogus case stmt from the |
| // substmt, but we have no way to do this right now. |
| CaseListIsErroneous = true; |
| } |
| } |
| } |
| |
| // Complain if we have a constant condition and we didn't find a match. |
| if (!CaseListIsErroneous && ShouldCheckConstantCond) { |
| // TODO: it would be nice if we printed enums as enums, chars as |
| // chars, etc. |
| Diag(CondExpr->getExprLoc(), diag::warn_missing_case_for_condition) |
| << ConstantCondValue.toString(10) |
| << CondExpr->getSourceRange(); |
| } |
| |
| // Check to see if switch is over an Enum and handles all of its |
| // values. We only issue a warning if there is not 'default:', but |
| // we still do the analysis to preserve this information in the AST |
| // (which can be used by flow-based analyes). |
| // |
| const EnumType *ET = CondTypeBeforePromotion->getAs<EnumType>(); |
| |
| // If switch has default case, then ignore it. |
| if (!CaseListIsErroneous && !HasConstantCond && ET) { |
| const EnumDecl *ED = ET->getDecl(); |
| typedef SmallVector<std::pair<llvm::APSInt, EnumConstantDecl*>, 64> |
| EnumValsTy; |
| EnumValsTy EnumVals; |
| |
| // Gather all enum values, set their type and sort them, |
| // allowing easier comparison with CaseVals. |
| for (EnumDecl::enumerator_iterator EDI = ED->enumerator_begin(); |
| EDI != ED->enumerator_end(); ++EDI) { |
| llvm::APSInt Val = EDI->getInitVal(); |
| AdjustAPSInt(Val, CondWidth, CondIsSigned); |
| EnumVals.push_back(std::make_pair(Val, *EDI)); |
| } |
| std::stable_sort(EnumVals.begin(), EnumVals.end(), CmpEnumVals); |
| EnumValsTy::iterator EIend = |
| std::unique(EnumVals.begin(), EnumVals.end(), EqEnumVals); |
| |
| // See which case values aren't in enum. |
| EnumValsTy::const_iterator EI = EnumVals.begin(); |
| for (CaseValsTy::const_iterator CI = CaseVals.begin(); |
| CI != CaseVals.end(); CI++) { |
| while (EI != EIend && EI->first < CI->first) |
| EI++; |
| if (EI == EIend || EI->first > CI->first) |
| Diag(CI->second->getLHS()->getExprLoc(), diag::warn_not_in_enum) |
| << CondTypeBeforePromotion; |
| } |
| // See which of case ranges aren't in enum |
| EI = EnumVals.begin(); |
| for (CaseRangesTy::const_iterator RI = CaseRanges.begin(); |
| RI != CaseRanges.end() && EI != EIend; RI++) { |
| while (EI != EIend && EI->first < RI->first) |
| EI++; |
| |
| if (EI == EIend || EI->first != RI->first) { |
| Diag(RI->second->getLHS()->getExprLoc(), diag::warn_not_in_enum) |
| << CondTypeBeforePromotion; |
| } |
| |
| llvm::APSInt Hi = |
| RI->second->getRHS()->EvaluateKnownConstInt(Context); |
| AdjustAPSInt(Hi, CondWidth, CondIsSigned); |
| while (EI != EIend && EI->first < Hi) |
| EI++; |
| if (EI == EIend || EI->first != Hi) |
| Diag(RI->second->getRHS()->getExprLoc(), diag::warn_not_in_enum) |
| << CondTypeBeforePromotion; |
| } |
| |
| // Check which enum vals aren't in switch |
| CaseValsTy::const_iterator CI = CaseVals.begin(); |
| CaseRangesTy::const_iterator RI = CaseRanges.begin(); |
| bool hasCasesNotInSwitch = false; |
| |
| SmallVector<DeclarationName,8> UnhandledNames; |
| |
| for (EI = EnumVals.begin(); EI != EIend; EI++){ |
| // Drop unneeded case values |
| llvm::APSInt CIVal; |
| while (CI != CaseVals.end() && CI->first < EI->first) |
| CI++; |
| |
| if (CI != CaseVals.end() && CI->first == EI->first) |
| continue; |
| |
| // Drop unneeded case ranges |
| for (; RI != CaseRanges.end(); RI++) { |
| llvm::APSInt Hi = |
| RI->second->getRHS()->EvaluateKnownConstInt(Context); |
| AdjustAPSInt(Hi, CondWidth, CondIsSigned); |
| if (EI->first <= Hi) |
| break; |
| } |
| |
| if (RI == CaseRanges.end() || EI->first < RI->first) { |
| hasCasesNotInSwitch = true; |
| UnhandledNames.push_back(EI->second->getDeclName()); |
| } |
| } |
| |
| if (TheDefaultStmt && UnhandledNames.empty()) |
| Diag(TheDefaultStmt->getDefaultLoc(), diag::warn_unreachable_default); |
| |
| // Produce a nice diagnostic if multiple values aren't handled. |
| switch (UnhandledNames.size()) { |
| case 0: break; |
| case 1: |
| Diag(CondExpr->getExprLoc(), TheDefaultStmt |
| ? diag::warn_def_missing_case1 : diag::warn_missing_case1) |
| << UnhandledNames[0]; |
| break; |
| case 2: |
| Diag(CondExpr->getExprLoc(), TheDefaultStmt |
| ? diag::warn_def_missing_case2 : diag::warn_missing_case2) |
| << UnhandledNames[0] << UnhandledNames[1]; |
| break; |
| case 3: |
| Diag(CondExpr->getExprLoc(), TheDefaultStmt |
| ? diag::warn_def_missing_case3 : diag::warn_missing_case3) |
| << UnhandledNames[0] << UnhandledNames[1] << UnhandledNames[2]; |
| break; |
| default: |
| Diag(CondExpr->getExprLoc(), TheDefaultStmt |
| ? diag::warn_def_missing_cases : diag::warn_missing_cases) |
| << (unsigned)UnhandledNames.size() |
| << UnhandledNames[0] << UnhandledNames[1] << UnhandledNames[2]; |
| break; |
| } |
| |
| if (!hasCasesNotInSwitch) |
| SS->setAllEnumCasesCovered(); |
| } |
| } |
| |
| DiagnoseEmptyStmtBody(CondExpr->getLocEnd(), BodyStmt, |
| diag::warn_empty_switch_body); |
| |
| // FIXME: If the case list was broken is some way, we don't have a good system |
| // to patch it up. Instead, just return the whole substmt as broken. |
| if (CaseListIsErroneous) |
| return StmtError(); |
| |
| return Owned(SS); |
| } |
| |
| void |
| Sema::DiagnoseAssignmentEnum(QualType DstType, QualType SrcType, |
| Expr *SrcExpr) { |
| if (Diags.getDiagnosticLevel(diag::warn_not_in_enum_assignment, |
| SrcExpr->getExprLoc()) == |
| DiagnosticsEngine::Ignored) |
| return; |
| |
| if (const EnumType *ET = DstType->getAs<EnumType>()) |
| if (!Context.hasSameType(SrcType, DstType) && |
| SrcType->isIntegerType()) { |
| if (!SrcExpr->isTypeDependent() && !SrcExpr->isValueDependent() && |
| SrcExpr->isIntegerConstantExpr(Context)) { |
| // Get the bitwidth of the enum value before promotions. |
| unsigned DstWidth = Context.getIntWidth(DstType); |
| bool DstIsSigned = DstType->isSignedIntegerOrEnumerationType(); |
| |
| llvm::APSInt RhsVal = SrcExpr->EvaluateKnownConstInt(Context); |
| AdjustAPSInt(RhsVal, DstWidth, DstIsSigned); |
| const EnumDecl *ED = ET->getDecl(); |
| typedef SmallVector<std::pair<llvm::APSInt, EnumConstantDecl *>, 64> |
| EnumValsTy; |
| EnumValsTy EnumVals; |
| |
| // Gather all enum values, set their type and sort them, |
| // allowing easier comparison with rhs constant. |
| for (EnumDecl::enumerator_iterator EDI = ED->enumerator_begin(); |
| EDI != ED->enumerator_end(); ++EDI) { |
| llvm::APSInt Val = EDI->getInitVal(); |
| AdjustAPSInt(Val, DstWidth, DstIsSigned); |
| EnumVals.push_back(std::make_pair(Val, *EDI)); |
| } |
| if (EnumVals.empty()) |
| return; |
| std::stable_sort(EnumVals.begin(), EnumVals.end(), CmpEnumVals); |
| EnumValsTy::iterator EIend = |
| std::unique(EnumVals.begin(), EnumVals.end(), EqEnumVals); |
| |
| // See which values aren't in the enum. |
| EnumValsTy::const_iterator EI = EnumVals.begin(); |
| while (EI != EIend && EI->first < RhsVal) |
| EI++; |
| if (EI == EIend || EI->first != RhsVal) { |
| Diag(SrcExpr->getExprLoc(), diag::warn_not_in_enum_assignment) |
| << DstType; |
| } |
| } |
| } |
| } |
| |
| StmtResult |
| Sema::ActOnWhileStmt(SourceLocation WhileLoc, FullExprArg Cond, |
| Decl *CondVar, Stmt *Body) { |
| ExprResult CondResult(Cond.release()); |
| |
| VarDecl *ConditionVar = 0; |
| if (CondVar) { |
| ConditionVar = cast<VarDecl>(CondVar); |
| CondResult = CheckConditionVariable(ConditionVar, WhileLoc, true); |
| if (CondResult.isInvalid()) |
| return StmtError(); |
| } |
| Expr *ConditionExpr = CondResult.take(); |
| if (!ConditionExpr) |
| return StmtError(); |
| |
| DiagnoseUnusedExprResult(Body); |
| |
| if (isa<NullStmt>(Body)) |
| getCurCompoundScope().setHasEmptyLoopBodies(); |
| |
| return Owned(new (Context) WhileStmt(Context, ConditionVar, ConditionExpr, |
| Body, WhileLoc)); |
| } |
| |
| StmtResult |
| Sema::ActOnDoStmt(SourceLocation DoLoc, Stmt *Body, |
| SourceLocation WhileLoc, SourceLocation CondLParen, |
| Expr *Cond, SourceLocation CondRParen) { |
| assert(Cond && "ActOnDoStmt(): missing expression"); |
| |
| ExprResult CondResult = CheckBooleanCondition(Cond, DoLoc); |
| if (CondResult.isInvalid()) |
| return StmtError(); |
| Cond = CondResult.take(); |
| |
| CondResult = ActOnFinishFullExpr(Cond, DoLoc); |
| if (CondResult.isInvalid()) |
| return StmtError(); |
| Cond = CondResult.take(); |
| |
| DiagnoseUnusedExprResult(Body); |
| |
| return Owned(new (Context) DoStmt(Body, Cond, DoLoc, WhileLoc, CondRParen)); |
| } |
| |
| namespace { |
| // This visitor will traverse a conditional statement and store all |
| // the evaluated decls into a vector. Simple is set to true if none |
| // of the excluded constructs are used. |
| class DeclExtractor : public EvaluatedExprVisitor<DeclExtractor> { |
| llvm::SmallPtrSet<VarDecl*, 8> &Decls; |
| SmallVectorImpl<SourceRange> &Ranges; |
| bool Simple; |
| public: |
| typedef EvaluatedExprVisitor<DeclExtractor> Inherited; |
| |
| DeclExtractor(Sema &S, llvm::SmallPtrSet<VarDecl*, 8> &Decls, |
| SmallVectorImpl<SourceRange> &Ranges) : |
| Inherited(S.Context), |
| Decls(Decls), |
| Ranges(Ranges), |
| Simple(true) {} |
| |
| bool isSimple() { return Simple; } |
| |
| // Replaces the method in EvaluatedExprVisitor. |
| void VisitMemberExpr(MemberExpr* E) { |
| Simple = false; |
| } |
| |
| // Any Stmt not whitelisted will cause the condition to be marked complex. |
| void VisitStmt(Stmt *S) { |
| Simple = false; |
| } |
| |
| void VisitBinaryOperator(BinaryOperator *E) { |
| Visit(E->getLHS()); |
| Visit(E->getRHS()); |
| } |
| |
| void VisitCastExpr(CastExpr *E) { |
| Visit(E->getSubExpr()); |
| } |
| |
| void VisitUnaryOperator(UnaryOperator *E) { |
| // Skip checking conditionals with derefernces. |
| if (E->getOpcode() == UO_Deref) |
| Simple = false; |
| else |
| Visit(E->getSubExpr()); |
| } |
| |
| void VisitConditionalOperator(ConditionalOperator *E) { |
| Visit(E->getCond()); |
| Visit(E->getTrueExpr()); |
| Visit(E->getFalseExpr()); |
| } |
| |
| void VisitParenExpr(ParenExpr *E) { |
| Visit(E->getSubExpr()); |
| } |
| |
| void VisitBinaryConditionalOperator(BinaryConditionalOperator *E) { |
| Visit(E->getOpaqueValue()->getSourceExpr()); |
| Visit(E->getFalseExpr()); |
| } |
| |
| void VisitIntegerLiteral(IntegerLiteral *E) { } |
| void VisitFloatingLiteral(FloatingLiteral *E) { } |
| void VisitCXXBoolLiteralExpr(CXXBoolLiteralExpr *E) { } |
| void VisitCharacterLiteral(CharacterLiteral *E) { } |
| void VisitGNUNullExpr(GNUNullExpr *E) { } |
| void VisitImaginaryLiteral(ImaginaryLiteral *E) { } |
| |
| void VisitDeclRefExpr(DeclRefExpr *E) { |
| VarDecl *VD = dyn_cast<VarDecl>(E->getDecl()); |
| if (!VD) return; |
| |
| Ranges.push_back(E->getSourceRange()); |
| |
| Decls.insert(VD); |
| } |
| |
| }; // end class DeclExtractor |
| |
| // DeclMatcher checks to see if the decls are used in a non-evauluated |
| // context. |
| class DeclMatcher : public EvaluatedExprVisitor<DeclMatcher> { |
| llvm::SmallPtrSet<VarDecl*, 8> &Decls; |
| bool FoundDecl; |
| |
| public: |
| typedef EvaluatedExprVisitor<DeclMatcher> Inherited; |
| |
| DeclMatcher(Sema &S, llvm::SmallPtrSet<VarDecl*, 8> &Decls, |
| Stmt *Statement) : |
| Inherited(S.Context), Decls(Decls), FoundDecl(false) { |
| if (!Statement) return; |
| |
| Visit(Statement); |
| } |
| |
| void VisitReturnStmt(ReturnStmt *S) { |
| FoundDecl = true; |
| } |
| |
| void VisitBreakStmt(BreakStmt *S) { |
| FoundDecl = true; |
| } |
| |
| void VisitGotoStmt(GotoStmt *S) { |
| FoundDecl = true; |
| } |
| |
| void VisitCastExpr(CastExpr *E) { |
| if (E->getCastKind() == CK_LValueToRValue) |
| CheckLValueToRValueCast(E->getSubExpr()); |
| else |
| Visit(E->getSubExpr()); |
| } |
| |
| void CheckLValueToRValueCast(Expr *E) { |
| E = E->IgnoreParenImpCasts(); |
| |
| if (isa<DeclRefExpr>(E)) { |
| return; |
| } |
| |
| if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) { |
| Visit(CO->getCond()); |
| CheckLValueToRValueCast(CO->getTrueExpr()); |
| CheckLValueToRValueCast(CO->getFalseExpr()); |
| return; |
| } |
| |
| if (BinaryConditionalOperator *BCO = |
| dyn_cast<BinaryConditionalOperator>(E)) { |
| CheckLValueToRValueCast(BCO->getOpaqueValue()->getSourceExpr()); |
| CheckLValueToRValueCast(BCO->getFalseExpr()); |
| return; |
| } |
| |
| Visit(E); |
| } |
| |
| void VisitDeclRefExpr(DeclRefExpr *E) { |
| if (VarDecl *VD = dyn_cast<VarDecl>(E->getDecl())) |
| if (Decls.count(VD)) |
| FoundDecl = true; |
| } |
| |
| bool FoundDeclInUse() { return FoundDecl; } |
| |
| }; // end class DeclMatcher |
| |
| void CheckForLoopConditionalStatement(Sema &S, Expr *Second, |
| Expr *Third, Stmt *Body) { |
| // Condition is empty |
| if (!Second) return; |
| |
| if (S.Diags.getDiagnosticLevel(diag::warn_variables_not_in_loop_body, |
| Second->getLocStart()) |
| == DiagnosticsEngine::Ignored) |
| return; |
| |
| PartialDiagnostic PDiag = S.PDiag(diag::warn_variables_not_in_loop_body); |
| llvm::SmallPtrSet<VarDecl*, 8> Decls; |
| SmallVector<SourceRange, 10> Ranges; |
| DeclExtractor DE(S, Decls, Ranges); |
| DE.Visit(Second); |
| |
| // Don't analyze complex conditionals. |
| if (!DE.isSimple()) return; |
| |
| // No decls found. |
| if (Decls.size() == 0) return; |
| |
| // Don't warn on volatile, static, or global variables. |
| for (llvm::SmallPtrSet<VarDecl*, 8>::iterator I = Decls.begin(), |
| E = Decls.end(); |
| I != E; ++I) |
| if ((*I)->getType().isVolatileQualified() || |
| (*I)->hasGlobalStorage()) return; |
| |
| if (DeclMatcher(S, Decls, Second).FoundDeclInUse() || |
| DeclMatcher(S, Decls, Third).FoundDeclInUse() || |
| DeclMatcher(S, Decls, Body).FoundDeclInUse()) |
| return; |
| |
| // Load decl names into diagnostic. |
| if (Decls.size() > 4) |
| PDiag << 0; |
| else { |
| PDiag << Decls.size(); |
| for (llvm::SmallPtrSet<VarDecl*, 8>::iterator I = Decls.begin(), |
| E = Decls.end(); |
| I != E; ++I) |
| PDiag << (*I)->getDeclName(); |
| } |
| |
| // Load SourceRanges into diagnostic if there is room. |
| // Otherwise, load the SourceRange of the conditional expression. |
| if (Ranges.size() <= PartialDiagnostic::MaxArguments) |
| for (SmallVectorImpl<SourceRange>::iterator I = Ranges.begin(), |
| E = Ranges.end(); |
| I != E; ++I) |
| PDiag << *I; |
| else |
| PDiag << Second->getSourceRange(); |
| |
| S.Diag(Ranges.begin()->getBegin(), PDiag); |
| } |
| |
| // If Statement is an incemement or decrement, return true and sets the |
| // variables Increment and DRE. |
| bool ProcessIterationStmt(Sema &S, Stmt* Statement, bool &Increment, |
| DeclRefExpr *&DRE) { |
| if (UnaryOperator *UO = dyn_cast<UnaryOperator>(Statement)) { |
| switch (UO->getOpcode()) { |
| default: return false; |
| case UO_PostInc: |
| case UO_PreInc: |
| Increment = true; |
| break; |
| case UO_PostDec: |
| case UO_PreDec: |
| Increment = false; |
| break; |
| } |
| DRE = dyn_cast<DeclRefExpr>(UO->getSubExpr()); |
| return DRE; |
| } |
| |
| if (CXXOperatorCallExpr *Call = dyn_cast<CXXOperatorCallExpr>(Statement)) { |
| FunctionDecl *FD = Call->getDirectCallee(); |
| if (!FD || !FD->isOverloadedOperator()) return false; |
| switch (FD->getOverloadedOperator()) { |
| default: return false; |
| case OO_PlusPlus: |
| Increment = true; |
| break; |
| case OO_MinusMinus: |
| Increment = false; |
| break; |
| } |
| DRE = dyn_cast<DeclRefExpr>(Call->getArg(0)); |
| return DRE; |
| } |
| |
| return false; |
| } |
| |
| // A visitor to determine if a continue statement is a subexpression. |
| class ContinueFinder : public EvaluatedExprVisitor<ContinueFinder> { |
| bool Found; |
| public: |
| ContinueFinder(Sema &S, Stmt* Body) : |
| Inherited(S.Context), |
| Found(false) { |
| Visit(Body); |
| } |
| |
| typedef EvaluatedExprVisitor<ContinueFinder> Inherited; |
| |
| void VisitContinueStmt(ContinueStmt* E) { |
| Found = true; |
| } |
| |
| bool ContinueFound() { return Found; } |
| |
| }; // end class ContinueFinder |
| |
| // Emit a warning when a loop increment/decrement appears twice per loop |
| // iteration. The conditions which trigger this warning are: |
| // 1) The last statement in the loop body and the third expression in the |
| // for loop are both increment or both decrement of the same variable |
| // 2) No continue statements in the loop body. |
| void CheckForRedundantIteration(Sema &S, Expr *Third, Stmt *Body) { |
| // Return when there is nothing to check. |
| if (!Body || !Third) return; |
| |
| if (S.Diags.getDiagnosticLevel(diag::warn_redundant_loop_iteration, |
| Third->getLocStart()) |
| == DiagnosticsEngine::Ignored) |
| return; |
| |
| // Get the last statement from the loop body. |
| CompoundStmt *CS = dyn_cast<CompoundStmt>(Body); |
| if (!CS || CS->body_empty()) return; |
| Stmt *LastStmt = CS->body_back(); |
| if (!LastStmt) return; |
| |
| bool LoopIncrement, LastIncrement; |
| DeclRefExpr *LoopDRE, *LastDRE; |
| |
| if (!ProcessIterationStmt(S, Third, LoopIncrement, LoopDRE)) return; |
| if (!ProcessIterationStmt(S, LastStmt, LastIncrement, LastDRE)) return; |
| |
| // Check that the two statements are both increments or both decrements |
| // on the same varaible. |
| if (LoopIncrement != LastIncrement || |
| LoopDRE->getDecl() != LastDRE->getDecl()) return; |
| |
| if (ContinueFinder(S, Body).ContinueFound()) return; |
| |
| S.Diag(LastDRE->getLocation(), diag::warn_redundant_loop_iteration) |
| << LastDRE->getDecl() << LastIncrement; |
| S.Diag(LoopDRE->getLocation(), diag::note_loop_iteration_here) |
| << LoopIncrement; |
| } |
| |
| } // end namespace |
| |
| StmtResult |
| Sema::ActOnForStmt(SourceLocation ForLoc, SourceLocation LParenLoc, |
| Stmt *First, FullExprArg second, Decl *secondVar, |
| FullExprArg third, |
| SourceLocation RParenLoc, Stmt *Body) { |
| if (!getLangOpts().CPlusPlus) { |
| if (DeclStmt *DS = dyn_cast_or_null<DeclStmt>(First)) { |
| // C99 6.8.5p3: The declaration part of a 'for' statement shall only |
| // declare identifiers for objects having storage class 'auto' or |
| // 'register'. |
| for (DeclStmt::decl_iterator DI=DS->decl_begin(), DE=DS->decl_end(); |
| DI!=DE; ++DI) { |
| VarDecl *VD = dyn_cast<VarDecl>(*DI); |
| if (VD && VD->isLocalVarDecl() && !VD->hasLocalStorage()) |
| VD = 0; |
| if (VD == 0) { |
| Diag((*DI)->getLocation(), diag::err_non_local_variable_decl_in_for); |
| (*DI)->setInvalidDecl(); |
| } |
| } |
| } |
| } |
| |
| CheckForLoopConditionalStatement(*this, second.get(), third.get(), Body); |
| CheckForRedundantIteration(*this, third.get(), Body); |
| |
| ExprResult SecondResult(second.release()); |
| VarDecl *ConditionVar = 0; |
| if (secondVar) { |
| ConditionVar = cast<VarDecl>(secondVar); |
| SecondResult = CheckConditionVariable(ConditionVar, ForLoc, true); |
| if (SecondResult.isInvalid()) |
| return StmtError(); |
| } |
| |
| Expr *Third = third.release().takeAs<Expr>(); |
| |
| DiagnoseUnusedExprResult(First); |
| DiagnoseUnusedExprResult(Third); |
| DiagnoseUnusedExprResult(Body); |
| |
| if (isa<NullStmt>(Body)) |
| getCurCompoundScope().setHasEmptyLoopBodies(); |
| |
| return Owned(new (Context) ForStmt(Context, First, |
| SecondResult.take(), ConditionVar, |
| Third, Body, ForLoc, LParenLoc, |
| RParenLoc)); |
| } |
| |
| /// In an Objective C collection iteration statement: |
| /// for (x in y) |
| /// x can be an arbitrary l-value expression. Bind it up as a |
| /// full-expression. |
| StmtResult Sema::ActOnForEachLValueExpr(Expr *E) { |
| // Reduce placeholder expressions here. Note that this rejects the |
| // use of pseudo-object l-values in this position. |
| ExprResult result = CheckPlaceholderExpr(E); |
| if (result.isInvalid()) return StmtError(); |
| E = result.take(); |
| |
| ExprResult FullExpr = ActOnFinishFullExpr(E); |
| if (FullExpr.isInvalid()) |
| return StmtError(); |
| return StmtResult(static_cast<Stmt*>(FullExpr.take())); |
| } |
| |
| ExprResult |
| Sema::CheckObjCForCollectionOperand(SourceLocation forLoc, Expr *collection) { |
| if (!collection) |
| return ExprError(); |
| |
| // Bail out early if we've got a type-dependent expression. |
| if (collection->isTypeDependent()) return Owned(collection); |
| |
| // Perform normal l-value conversion. |
| ExprResult result = DefaultFunctionArrayLvalueConversion(collection); |
| if (result.isInvalid()) |
| return ExprError(); |
| collection = result.take(); |
| |
| // The operand needs to have object-pointer type. |
| // TODO: should we do a contextual conversion? |
| const ObjCObjectPointerType *pointerType = |
| collection->getType()->getAs<ObjCObjectPointerType>(); |
| if (!pointerType) |
| return Diag(forLoc, diag::err_collection_expr_type) |
| << collection->getType() << collection->getSourceRange(); |
| |
| // Check that the operand provides |
| // - countByEnumeratingWithState:objects:count: |
| const ObjCObjectType *objectType = pointerType->getObjectType(); |
| ObjCInterfaceDecl *iface = objectType->getInterface(); |
| |
| // If we have a forward-declared type, we can't do this check. |
| // Under ARC, it is an error not to have a forward-declared class. |
| if (iface && |
| RequireCompleteType(forLoc, QualType(objectType, 0), |
| getLangOpts().ObjCAutoRefCount |
| ? diag::err_arc_collection_forward |
| : 0, |
| collection)) { |
| // Otherwise, if we have any useful type information, check that |
| // the type declares the appropriate method. |
| } else if (iface || !objectType->qual_empty()) { |
| IdentifierInfo *selectorIdents[] = { |
| &Context.Idents.get("countByEnumeratingWithState"), |
| &Context.Idents.get("objects"), |
| &Context.Idents.get("count") |
| }; |
| Selector selector = Context.Selectors.getSelector(3, &selectorIdents[0]); |
| |
| ObjCMethodDecl *method = 0; |
| |
| // If there's an interface, look in both the public and private APIs. |
| if (iface) { |
| method = iface->lookupInstanceMethod(selector); |
| if (!method) method = iface->lookupPrivateMethod(selector); |
| } |
| |
| // Also check protocol qualifiers. |
| if (!method) |
| method = LookupMethodInQualifiedType(selector, pointerType, |
| /*instance*/ true); |
| |
| // If we didn't find it anywhere, give up. |
| if (!method) { |
| Diag(forLoc, diag::warn_collection_expr_type) |
| << collection->getType() << selector << collection->getSourceRange(); |
| } |
| |
| // TODO: check for an incompatible signature? |
| } |
| |
| // Wrap up any cleanups in the expression. |
| return Owned(collection); |
| } |
| |
| StmtResult |
| Sema::ActOnObjCForCollectionStmt(SourceLocation ForLoc, |
| Stmt *First, Expr *collection, |
| SourceLocation RParenLoc) { |
| |
| ExprResult CollectionExprResult = |
| CheckObjCForCollectionOperand(ForLoc, collection); |
| |
| if (First) { |
| QualType FirstType; |
| if (DeclStmt *DS = dyn_cast<DeclStmt>(First)) { |
| if (!DS->isSingleDecl()) |
| return StmtError(Diag((*DS->decl_begin())->getLocation(), |
| diag::err_toomany_element_decls)); |
| |
| VarDecl *D = dyn_cast<VarDecl>(DS->getSingleDecl()); |
| if (!D || D->isInvalidDecl()) |
| return StmtError(); |
| |
| FirstType = D->getType(); |
| // C99 6.8.5p3: The declaration part of a 'for' statement shall only |
| // declare identifiers for objects having storage class 'auto' or |
| // 'register'. |
| if (!D->hasLocalStorage()) |
| return StmtError(Diag(D->getLocation(), |
| diag::err_non_local_variable_decl_in_for)); |
| |
| // If the type contained 'auto', deduce the 'auto' to 'id'. |
| if (FirstType->getContainedAutoType()) { |
| OpaqueValueExpr OpaqueId(D->getLocation(), Context.getObjCIdType(), |
| VK_RValue); |
| Expr *DeducedInit = &OpaqueId; |
| if (DeduceAutoType(D->getTypeSourceInfo(), DeducedInit, FirstType) == |
| DAR_Failed) |
| DiagnoseAutoDeductionFailure(D, DeducedInit); |
| if (FirstType.isNull()) { |
| D->setInvalidDecl(); |
| return StmtError(); |
| } |
| |
| D->setType(FirstType); |
| |
| if (ActiveTemplateInstantiations.empty()) { |
| SourceLocation Loc = |
| D->getTypeSourceInfo()->getTypeLoc().getBeginLoc(); |
| Diag(Loc, diag::warn_auto_var_is_id) |
| << D->getDeclName(); |
| } |
| } |
| |
| } else { |
| Expr *FirstE = cast<Expr>(First); |
| if (!FirstE->isTypeDependent() && !FirstE->isLValue()) |
| return StmtError(Diag(First->getLocStart(), |
| diag::err_selector_element_not_lvalue) |
| << First->getSourceRange()); |
| |
| FirstType = static_cast<Expr*>(First)->getType(); |
| if (FirstType.isConstQualified()) |
| Diag(ForLoc, diag::err_selector_element_const_type) |
| << FirstType << First->getSourceRange(); |
| } |
| if (!FirstType->isDependentType() && |
| !FirstType->isObjCObjectPointerType() && |
| !FirstType->isBlockPointerType()) |
| return StmtError(Diag(ForLoc, diag::err_selector_element_type) |
| << FirstType << First->getSourceRange()); |
| } |
| |
| if (CollectionExprResult.isInvalid()) |
| return StmtError(); |
| |
| CollectionExprResult = ActOnFinishFullExpr(CollectionExprResult.take()); |
| if (CollectionExprResult.isInvalid()) |
| return StmtError(); |
| |
| return Owned(new (Context) ObjCForCollectionStmt(First, |
| CollectionExprResult.take(), 0, |
| ForLoc, RParenLoc)); |
| } |
| |
| /// Finish building a variable declaration for a for-range statement. |
| /// \return true if an error occurs. |
| static bool FinishForRangeVarDecl(Sema &SemaRef, VarDecl *Decl, Expr *Init, |
| SourceLocation Loc, int DiagID) { |
| // Deduce the type for the iterator variable now rather than leaving it to |
| // AddInitializerToDecl, so we can produce a more suitable diagnostic. |
| QualType InitType; |
| if ((!isa<InitListExpr>(Init) && Init->getType()->isVoidType()) || |
| SemaRef.DeduceAutoType(Decl->getTypeSourceInfo(), Init, InitType) == |
| Sema::DAR_Failed) |
| SemaRef.Diag(Loc, DiagID) << Init->getType(); |
| if (InitType.isNull()) { |
| Decl->setInvalidDecl(); |
| return true; |
| } |
| Decl->setType(InitType); |
| |
| // In ARC, infer lifetime. |
| // FIXME: ARC may want to turn this into 'const __unsafe_unretained' if |
| // we're doing the equivalent of fast iteration. |
| if (SemaRef.getLangOpts().ObjCAutoRefCount && |
| SemaRef.inferObjCARCLifetime(Decl)) |
| Decl->setInvalidDecl(); |
| |
| SemaRef.AddInitializerToDecl(Decl, Init, /*DirectInit=*/false, |
| /*TypeMayContainAuto=*/false); |
| SemaRef.FinalizeDeclaration(Decl); |
| SemaRef.CurContext->addHiddenDecl(Decl); |
| return false; |
| } |
| |
| namespace { |
| |
| /// Produce a note indicating which begin/end function was implicitly called |
| /// by a C++11 for-range statement. This is often not obvious from the code, |
| /// nor from the diagnostics produced when analysing the implicit expressions |
| /// required in a for-range statement. |
| void NoteForRangeBeginEndFunction(Sema &SemaRef, Expr *E, |
| Sema::BeginEndFunction BEF) { |
| CallExpr *CE = dyn_cast<CallExpr>(E); |
| if (!CE) |
| return; |
| FunctionDecl *D = dyn_cast<FunctionDecl>(CE->getCalleeDecl()); |
| if (!D) |
| return; |
| SourceLocation Loc = D->getLocation(); |
| |
| std::string Description; |
| bool IsTemplate = false; |
| if (FunctionTemplateDecl *FunTmpl = D->getPrimaryTemplate()) { |
| Description = SemaRef.getTemplateArgumentBindingsText( |
| FunTmpl->getTemplateParameters(), *D->getTemplateSpecializationArgs()); |
| IsTemplate = true; |
| } |
| |
| SemaRef.Diag(Loc, diag::note_for_range_begin_end) |
| << BEF << IsTemplate << Description << E->getType(); |
| } |
| |
| /// Build a variable declaration for a for-range statement. |
| VarDecl *BuildForRangeVarDecl(Sema &SemaRef, SourceLocation Loc, |
| QualType Type, const char *Name) { |
| DeclContext *DC = SemaRef.CurContext; |
| IdentifierInfo *II = &SemaRef.PP.getIdentifierTable().get(Name); |
| TypeSourceInfo *TInfo = SemaRef.Context.getTrivialTypeSourceInfo(Type, Loc); |
| VarDecl *Decl = VarDecl::Create(SemaRef.Context, DC, Loc, Loc, II, Type, |
| TInfo, SC_None); |
| Decl->setImplicit(); |
| return Decl; |
| } |
| |
| } |
| |
| static bool ObjCEnumerationCollection(Expr *Collection) { |
| return !Collection->isTypeDependent() |
| && Collection->getType()->getAs<ObjCObjectPointerType>() != 0; |
| } |
| |
| /// ActOnCXXForRangeStmt - Check and build a C++11 for-range statement. |
| /// |
| /// C++11 [stmt.ranged]: |
| /// A range-based for statement is equivalent to |
| /// |
| /// { |
| /// auto && __range = range-init; |
| /// for ( auto __begin = begin-expr, |
| /// __end = end-expr; |
| /// __begin != __end; |
| /// ++__begin ) { |
| /// for-range-declaration = *__begin; |
| /// statement |
| /// } |
| /// } |
| /// |
| /// The body of the loop is not available yet, since it cannot be analysed until |
| /// we have determined the type of the for-range-declaration. |
| StmtResult |
| Sema::ActOnCXXForRangeStmt(SourceLocation ForLoc, |
| Stmt *First, SourceLocation ColonLoc, Expr *Range, |
| SourceLocation RParenLoc, BuildForRangeKind Kind) { |
| if (!First) |
| return StmtError(); |
| |
| if (Range && ObjCEnumerationCollection(Range)) |
| return ActOnObjCForCollectionStmt(ForLoc, First, Range, RParenLoc); |
| |
| DeclStmt *DS = dyn_cast<DeclStmt>(First); |
| assert(DS && "first part of for range not a decl stmt"); |
| |
| if (!DS->isSingleDecl()) { |
| Diag(DS->getStartLoc(), diag::err_type_defined_in_for_range); |
| return StmtError(); |
| } |
| |
| Decl *LoopVar = DS->getSingleDecl(); |
| if (LoopVar->isInvalidDecl() || !Range || |
| DiagnoseUnexpandedParameterPack(Range, UPPC_Expression)) { |
| LoopVar->setInvalidDecl(); |
| return StmtError(); |
| } |
| |
| // Build auto && __range = range-init |
| SourceLocation RangeLoc = Range->getLocStart(); |
| VarDecl *RangeVar = BuildForRangeVarDecl(*this, RangeLoc, |
| Context.getAutoRRefDeductType(), |
| "__range"); |
| if (FinishForRangeVarDecl(*this, RangeVar, Range, RangeLoc, |
| diag::err_for_range_deduction_failure)) { |
| LoopVar->setInvalidDecl(); |
| return StmtError(); |
| } |
| |
| // Claim the type doesn't contain auto: we've already done the checking. |
| DeclGroupPtrTy RangeGroup = |
| BuildDeclaratorGroup(llvm::MutableArrayRef<Decl *>((Decl **)&RangeVar, 1), |
| /*TypeMayContainAuto=*/ false); |
| StmtResult RangeDecl = ActOnDeclStmt(RangeGroup, RangeLoc, RangeLoc); |
| if (RangeDecl.isInvalid()) { |
| LoopVar->setInvalidDecl(); |
| return StmtError(); |
| } |
| |
| return BuildCXXForRangeStmt(ForLoc, ColonLoc, RangeDecl.get(), |
| /*BeginEndDecl=*/0, /*Cond=*/0, /*Inc=*/0, DS, |
| RParenLoc, Kind); |
| } |
| |
| /// \brief Create the initialization, compare, and increment steps for |
| /// the range-based for loop expression. |
| /// This function does not handle array-based for loops, |
| /// which are created in Sema::BuildCXXForRangeStmt. |
| /// |
| /// \returns a ForRangeStatus indicating success or what kind of error occurred. |
| /// BeginExpr and EndExpr are set and FRS_Success is returned on success; |
| /// CandidateSet and BEF are set and some non-success value is returned on |
| /// failure. |
| static Sema::ForRangeStatus BuildNonArrayForRange(Sema &SemaRef, Scope *S, |
| Expr *BeginRange, Expr *EndRange, |
| QualType RangeType, |
| VarDecl *BeginVar, |
| VarDecl *EndVar, |
| SourceLocation ColonLoc, |
| OverloadCandidateSet *CandidateSet, |
| ExprResult *BeginExpr, |
| ExprResult *EndExpr, |
| Sema::BeginEndFunction *BEF) { |
| DeclarationNameInfo BeginNameInfo( |
| &SemaRef.PP.getIdentifierTable().get("begin"), ColonLoc); |
| DeclarationNameInfo EndNameInfo(&SemaRef.PP.getIdentifierTable().get("end"), |
| ColonLoc); |
| |
| LookupResult BeginMemberLookup(SemaRef, BeginNameInfo, |
| Sema::LookupMemberName); |
| LookupResult EndMemberLookup(SemaRef, EndNameInfo, Sema::LookupMemberName); |
| |
| if (CXXRecordDecl *D = RangeType->getAsCXXRecordDecl()) { |
| // - if _RangeT is a class type, the unqualified-ids begin and end are |
| // looked up in the scope of class _RangeT as if by class member access |
| // lookup (3.4.5), and if either (or both) finds at least one |
| // declaration, begin-expr and end-expr are __range.begin() and |
| // __range.end(), respectively; |
| SemaRef.LookupQualifiedName(BeginMemberLookup, D); |
| SemaRef.LookupQualifiedName(EndMemberLookup, D); |
| |
| if (BeginMemberLookup.empty() != EndMemberLookup.empty()) { |
| SourceLocation RangeLoc = BeginVar->getLocation(); |
| *BEF = BeginMemberLookup.empty() ? Sema::BEF_end : Sema::BEF_begin; |
| |
| SemaRef.Diag(RangeLoc, diag::err_for_range_member_begin_end_mismatch) |
| << RangeLoc << BeginRange->getType() << *BEF; |
| return Sema::FRS_DiagnosticIssued; |
| } |
| } else { |
| // - otherwise, begin-expr and end-expr are begin(__range) and |
| // end(__range), respectively, where begin and end are looked up with |
| // argument-dependent lookup (3.4.2). For the purposes of this name |
| // lookup, namespace std is an associated namespace. |
| |
| } |
| |
| *BEF = Sema::BEF_begin; |
| Sema::ForRangeStatus RangeStatus = |
| SemaRef.BuildForRangeBeginEndCall(S, ColonLoc, ColonLoc, BeginVar, |
| Sema::BEF_begin, BeginNameInfo, |
| BeginMemberLookup, CandidateSet, |
| BeginRange, BeginExpr); |
| |
| if (RangeStatus != Sema::FRS_Success) |
| return RangeStatus; |
| if (FinishForRangeVarDecl(SemaRef, BeginVar, BeginExpr->get(), ColonLoc, |
| diag::err_for_range_iter_deduction_failure)) { |
| NoteForRangeBeginEndFunction(SemaRef, BeginExpr->get(), *BEF); |
| return Sema::FRS_DiagnosticIssued; |
| } |
| |
| *BEF = Sema::BEF_end; |
| RangeStatus = |
| SemaRef.BuildForRangeBeginEndCall(S, ColonLoc, ColonLoc, EndVar, |
| Sema::BEF_end, EndNameInfo, |
| EndMemberLookup, CandidateSet, |
| EndRange, EndExpr); |
| if (RangeStatus != Sema::FRS_Success) |
| return RangeStatus; |
| if (FinishForRangeVarDecl(SemaRef, EndVar, EndExpr->get(), ColonLoc, |
| diag::err_for_range_iter_deduction_failure)) { |
| NoteForRangeBeginEndFunction(SemaRef, EndExpr->get(), *BEF); |
| return Sema::FRS_DiagnosticIssued; |
| } |
| return Sema::FRS_Success; |
| } |
| |
| /// Speculatively attempt to dereference an invalid range expression. |
| /// If the attempt fails, this function will return a valid, null StmtResult |
| /// and emit no diagnostics. |
| static StmtResult RebuildForRangeWithDereference(Sema &SemaRef, Scope *S, |
| SourceLocation ForLoc, |
| Stmt *LoopVarDecl, |
| SourceLocation ColonLoc, |
| Expr *Range, |
| SourceLocation RangeLoc, |
| SourceLocation RParenLoc) { |
| // Determine whether we can rebuild the for-range statement with a |
| // dereferenced range expression. |
| ExprResult AdjustedRange; |
| { |
| Sema::SFINAETrap Trap(SemaRef); |
| |
| AdjustedRange = SemaRef.BuildUnaryOp(S, RangeLoc, UO_Deref, Range); |
| if (AdjustedRange.isInvalid()) |
| return StmtResult(); |
| |
| StmtResult SR = |
| SemaRef.ActOnCXXForRangeStmt(ForLoc, LoopVarDecl, ColonLoc, |
| AdjustedRange.get(), RParenLoc, |
| Sema::BFRK_Check); |
| if (SR.isInvalid()) |
| return StmtResult(); |
| } |
| |
| // The attempt to dereference worked well enough that it could produce a valid |
| // loop. Produce a fixit, and rebuild the loop with diagnostics enabled, in |
| // case there are any other (non-fatal) problems with it. |
| SemaRef.Diag(RangeLoc, diag::err_for_range_dereference) |
| << Range->getType() << FixItHint::CreateInsertion(RangeLoc, "*"); |
| return SemaRef.ActOnCXXForRangeStmt(ForLoc, LoopVarDecl, ColonLoc, |
| AdjustedRange.get(), RParenLoc, |
| Sema::BFRK_Rebuild); |
| } |
| |
| namespace { |
| /// RAII object to automatically invalidate a declaration if an error occurs. |
| struct InvalidateOnErrorScope { |
| InvalidateOnErrorScope(Sema &SemaRef, Decl *D, bool Enabled) |
| : Trap(SemaRef.Diags), D(D), Enabled(Enabled) {} |
| ~InvalidateOnErrorScope() { |
| if (Enabled && Trap.hasErrorOccurred()) |
| D->setInvalidDecl(); |
| } |
| |
| DiagnosticErrorTrap Trap; |
| Decl *D; |
| bool Enabled; |
| }; |
| } |
| |
| /// BuildCXXForRangeStmt - Build or instantiate a C++11 for-range statement. |
| StmtResult |
| Sema::BuildCXXForRangeStmt(SourceLocation ForLoc, SourceLocation ColonLoc, |
| Stmt *RangeDecl, Stmt *BeginEnd, Expr *Cond, |
| Expr *Inc, Stmt *LoopVarDecl, |
| SourceLocation RParenLoc, BuildForRangeKind Kind) { |
| Scope *S = getCurScope(); |
| |
| DeclStmt *RangeDS = cast<DeclStmt>(RangeDecl); |
| VarDecl *RangeVar = cast<VarDecl>(RangeDS->getSingleDecl()); |
| QualType RangeVarType = RangeVar->getType(); |
| |
| DeclStmt *LoopVarDS = cast<DeclStmt>(LoopVarDecl); |
| VarDecl *LoopVar = cast<VarDecl>(LoopVarDS->getSingleDecl()); |
| |
| // If we hit any errors, mark the loop variable as invalid if its type |
| // contains 'auto'. |
| InvalidateOnErrorScope Invalidate(*this, LoopVar, |
| LoopVar->getType()->isUndeducedType()); |
| |
| StmtResult BeginEndDecl = BeginEnd; |
| ExprResult NotEqExpr = Cond, IncrExpr = Inc; |
| |
| if (RangeVarType->isDependentType()) { |
| // The range is implicitly used as a placeholder when it is dependent. |
| RangeVar->markUsed(Context); |
| |
| // Deduce any 'auto's in the loop variable as 'DependentTy'. We'll fill |
| // them in properly when we instantiate the loop. |
| if (!LoopVar->isInvalidDecl() && Kind != BFRK_Check) |
| LoopVar->setType(SubstAutoType(LoopVar->getType(), Context.DependentTy)); |
| } else if (!BeginEndDecl.get()) { |
| SourceLocation RangeLoc = RangeVar->getLocation(); |
| |
| const QualType RangeVarNonRefType = RangeVarType.getNonReferenceType(); |
| |
| ExprResult BeginRangeRef = BuildDeclRefExpr(RangeVar, RangeVarNonRefType, |
| VK_LValue, ColonLoc); |
| if (BeginRangeRef.isInvalid()) |
| return StmtError(); |
| |
| ExprResult EndRangeRef = BuildDeclRefExpr(RangeVar, RangeVarNonRefType, |
| VK_LValue, ColonLoc); |
| if (EndRangeRef.isInvalid()) |
| return StmtError(); |
| |
| QualType AutoType = Context.getAutoDeductType(); |
| Expr *Range = RangeVar->getInit(); |
| if (!Range) |
| return StmtError(); |
| QualType RangeType = Range->getType(); |
| |
| if (RequireCompleteType(RangeLoc, RangeType, |
| diag::err_for_range_incomplete_type)) |
| return StmtError(); |
| |
| // Build auto __begin = begin-expr, __end = end-expr. |
| VarDecl *BeginVar = BuildForRangeVarDecl(*this, ColonLoc, AutoType, |
| "__begin"); |
| VarDecl *EndVar = BuildForRangeVarDecl(*this, ColonLoc, AutoType, |
| "__end"); |
| |
| // Build begin-expr and end-expr and attach to __begin and __end variables. |
| ExprResult BeginExpr, EndExpr; |
| if (const ArrayType *UnqAT = RangeType->getAsArrayTypeUnsafe()) { |
| // - if _RangeT is an array type, begin-expr and end-expr are __range and |
| // __range + __bound, respectively, where __bound is the array bound. If |
| // _RangeT is an array of unknown size or an array of incomplete type, |
| // the program is ill-formed; |
| |
| // begin-expr is __range. |
| BeginExpr = BeginRangeRef; |
| if (FinishForRangeVarDecl(*this, BeginVar, BeginRangeRef.get(), ColonLoc, |
| diag::err_for_range_iter_deduction_failure)) { |
| NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin); |
| return StmtError(); |
| } |
| |
| // Find the array bound. |
| ExprResult BoundExpr; |
| if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(UnqAT)) |
| BoundExpr = Owned(IntegerLiteral::Create(Context, CAT->getSize(), |
| Context.getPointerDiffType(), |
| RangeLoc)); |
| else if (const VariableArrayType *VAT = |
| dyn_cast<VariableArrayType>(UnqAT)) |
| BoundExpr = VAT->getSizeExpr(); |
| else { |
| // Can't be a DependentSizedArrayType or an IncompleteArrayType since |
| // UnqAT is not incomplete and Range is not type-dependent. |
| llvm_unreachable("Unexpected array type in for-range"); |
| } |
| |
| // end-expr is __range + __bound. |
| EndExpr = ActOnBinOp(S, ColonLoc, tok::plus, EndRangeRef.get(), |
| BoundExpr.get()); |
| if (EndExpr.isInvalid()) |
| return StmtError(); |
| if (FinishForRangeVarDecl(*this, EndVar, EndExpr.get(), ColonLoc, |
| diag::err_for_range_iter_deduction_failure)) { |
| NoteForRangeBeginEndFunction(*this, EndExpr.get(), BEF_end); |
| return StmtError(); |
| } |
| } else { |
| OverloadCandidateSet CandidateSet(RangeLoc); |
| Sema::BeginEndFunction BEFFailure; |
| ForRangeStatus RangeStatus = |
| BuildNonArrayForRange(*this, S, BeginRangeRef.get(), |
| EndRangeRef.get(), RangeType, |
| BeginVar, EndVar, ColonLoc, &CandidateSet, |
| &BeginExpr, &EndExpr, &BEFFailure); |
| |
| if (Kind == BFRK_Build && RangeStatus == FRS_NoViableFunction && |
| BEFFailure == BEF_begin) { |
| // If the range is being built from an array parameter, emit a |
| // a diagnostic that it is being treated as a pointer. |
| if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Range)) { |
| if (ParmVarDecl *PVD = dyn_cast<ParmVarDecl>(DRE->getDecl())) { |
| QualType ArrayTy = PVD->getOriginalType(); |
| QualType PointerTy = PVD->getType(); |
| if (PointerTy->isPointerType() && ArrayTy->isArrayType()) { |
| Diag(Range->getLocStart(), diag::err_range_on_array_parameter) |
| << RangeLoc << PVD << ArrayTy << PointerTy; |
| Diag(PVD->getLocation(), diag::note_declared_at); |
| return StmtError(); |
| } |
| } |
| } |
| |
| // If building the range failed, try dereferencing the range expression |
| // unless a diagnostic was issued or the end function is problematic. |
| StmtResult SR = RebuildForRangeWithDereference(*this, S, ForLoc, |
| LoopVarDecl, ColonLoc, |
| Range, RangeLoc, |
| RParenLoc); |
| if (SR.isInvalid() || SR.isUsable()) |
| return SR; |
| } |
| |
| // Otherwise, emit diagnostics if we haven't already. |
| if (RangeStatus == FRS_NoViableFunction) { |
| Expr *Range = BEFFailure ? EndRangeRef.get() : BeginRangeRef.get(); |
| Diag(Range->getLocStart(), diag::err_for_range_invalid) |
| << RangeLoc << Range->getType() << BEFFailure; |
| CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Range); |
| } |
| // Return an error if no fix was discovered. |
| if (RangeStatus != FRS_Success) |
| return StmtError(); |
| } |
| |
| assert(!BeginExpr.isInvalid() && !EndExpr.isInvalid() && |
| "invalid range expression in for loop"); |
| |
| // C++11 [dcl.spec.auto]p7: BeginType and EndType must be the same. |
| QualType BeginType = BeginVar->getType(), EndType = EndVar->getType(); |
| if (!Context.hasSameType(BeginType, EndType)) { |
| Diag(RangeLoc, diag::err_for_range_begin_end_types_differ) |
| << BeginType << EndType; |
| NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin); |
| NoteForRangeBeginEndFunction(*this, EndExpr.get(), BEF_end); |
| } |
| |
| Decl *BeginEndDecls[] = { BeginVar, EndVar }; |
| // Claim the type doesn't contain auto: we've already done the checking. |
| DeclGroupPtrTy BeginEndGroup = |
| BuildDeclaratorGroup(llvm::MutableArrayRef<Decl *>(BeginEndDecls, 2), |
| /*TypeMayContainAuto=*/ false); |
| BeginEndDecl = ActOnDeclStmt(BeginEndGroup, ColonLoc, ColonLoc); |
| |
| const QualType BeginRefNonRefType = BeginType.getNonReferenceType(); |
| ExprResult BeginRef = BuildDeclRefExpr(BeginVar, BeginRefNonRefType, |
| VK_LValue, ColonLoc); |
| if (BeginRef.isInvalid()) |
| return StmtError(); |
| |
| ExprResult EndRef = BuildDeclRefExpr(EndVar, EndType.getNonReferenceType(), |
| VK_LValue, ColonLoc); |
| if (EndRef.isInvalid()) |
| return StmtError(); |
| |
| // Build and check __begin != __end expression. |
| NotEqExpr = ActOnBinOp(S, ColonLoc, tok::exclaimequal, |
| BeginRef.get(), EndRef.get()); |
| NotEqExpr = ActOnBooleanCondition(S, ColonLoc, NotEqExpr.get()); |
| NotEqExpr = ActOnFinishFullExpr(NotEqExpr.get()); |
| if (NotEqExpr.isInvalid()) { |
| Diag(RangeLoc, diag::note_for_range_invalid_iterator) |
| << RangeLoc << 0 << BeginRangeRef.get()->getType(); |
| NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin); |
| if (!Context.hasSameType(BeginType, EndType)) |
| NoteForRangeBeginEndFunction(*this, EndExpr.get(), BEF_end); |
| return StmtError(); |
| } |
| |
| // Build and check ++__begin expression. |
| BeginRef = BuildDeclRefExpr(BeginVar, BeginRefNonRefType, |
| VK_LValue, ColonLoc); |
| if (BeginRef.isInvalid()) |
| return StmtError(); |
| |
| IncrExpr = ActOnUnaryOp(S, ColonLoc, tok::plusplus, BeginRef.get()); |
| IncrExpr = ActOnFinishFullExpr(IncrExpr.get()); |
| if (IncrExpr.isInvalid()) { |
| Diag(RangeLoc, diag::note_for_range_invalid_iterator) |
| << RangeLoc << 2 << BeginRangeRef.get()->getType() ; |
| NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin); |
| return StmtError(); |
| } |
| |
| // Build and check *__begin expression. |
| BeginRef = BuildDeclRefExpr(BeginVar, BeginRefNonRefType, |
| VK_LValue, ColonLoc); |
| if (BeginRef.isInvalid()) |
| return StmtError(); |
| |
| ExprResult DerefExpr = ActOnUnaryOp(S, ColonLoc, tok::star, BeginRef.get()); |
| if (DerefExpr.isInvalid()) { |
| Diag(RangeLoc, diag::note_for_range_invalid_iterator) |
| << RangeLoc << 1 << BeginRangeRef.get()->getType(); |
| NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin); |
| return StmtError(); |
| } |
| |
| // Attach *__begin as initializer for VD. Don't touch it if we're just |
| // trying to determine whether this would be a valid range. |
| if (!LoopVar->isInvalidDecl() && Kind != BFRK_Check) { |
| AddInitializerToDecl(LoopVar, DerefExpr.get(), /*DirectInit=*/false, |
| /*TypeMayContainAuto=*/true); |
| if (LoopVar->isInvalidDecl()) |
| NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin); |
| } |
| } |
| |
| // Don't bother to actually allocate the result if we're just trying to |
| // determine whether it would be valid. |
| if (Kind == BFRK_Check) |
| return StmtResult(); |
| |
| return Owned(new (Context) CXXForRangeStmt(RangeDS, |
| cast_or_null<DeclStmt>(BeginEndDecl.get()), |
| NotEqExpr.take(), IncrExpr.take(), |
| LoopVarDS, /*Body=*/0, ForLoc, |
| ColonLoc, RParenLoc)); |
| } |
| |
| /// FinishObjCForCollectionStmt - Attach the body to a objective-C foreach |
| /// statement. |
| StmtResult Sema::FinishObjCForCollectionStmt(Stmt *S, Stmt *B) { |
| if (!S || !B) |
| return StmtError(); |
| ObjCForCollectionStmt * ForStmt = cast<ObjCForCollectionStmt>(S); |
| |
| ForStmt->setBody(B); |
| return S; |
| } |
| |
| /// FinishCXXForRangeStmt - Attach the body to a C++0x for-range statement. |
| /// This is a separate step from ActOnCXXForRangeStmt because analysis of the |
| /// body cannot be performed until after the type of the range variable is |
| /// determined. |
| StmtResult Sema::FinishCXXForRangeStmt(Stmt *S, Stmt *B) { |
| if (!S || !B) |
| return StmtError(); |
| |
| if (isa<ObjCForCollectionStmt>(S)) |
| return FinishObjCForCollectionStmt(S, B); |
| |
| CXXForRangeStmt *ForStmt = cast<CXXForRangeStmt>(S); |
| ForStmt->setBody(B); |
| |
| DiagnoseEmptyStmtBody(ForStmt->getRParenLoc(), B, |
| diag::warn_empty_range_based_for_body); |
| |
| return S; |
| } |
| |
| StmtResult Sema::ActOnGotoStmt(SourceLocation GotoLoc, |
| SourceLocation LabelLoc, |
| LabelDecl *TheDecl) { |
| getCurFunction()->setHasBranchIntoScope(); |
| TheDecl->markUsed(Context); |
| return Owned(new (Context) GotoStmt(TheDecl, GotoLoc, LabelLoc)); |
| } |
| |
| StmtResult |
| Sema::ActOnIndirectGotoStmt(SourceLocation GotoLoc, SourceLocation StarLoc, |
| Expr *E) { |
| // Convert operand to void* |
| if (!E->isTypeDependent()) { |
| QualType ETy = E->getType(); |
| QualType DestTy = Context.getPointerType(Context.VoidTy.withConst()); |
| ExprResult ExprRes = Owned(E); |
| AssignConvertType ConvTy = |
| CheckSingleAssignmentConstraints(DestTy, ExprRes); |
| if (ExprRes.isInvalid()) |
| return StmtError(); |
| E = ExprRes.take(); |
| if (DiagnoseAssignmentResult(ConvTy, StarLoc, DestTy, ETy, E, AA_Passing)) |
| return StmtError(); |
| } |
| |
| ExprResult ExprRes = ActOnFinishFullExpr(E); |
| if (ExprRes.isInvalid()) |
| return StmtError(); |
| E = ExprRes.take(); |
| |
| getCurFunction()->setHasIndirectGoto(); |
| |
| return Owned(new (Context) IndirectGotoStmt(GotoLoc, StarLoc, E)); |
| } |
| |
| StmtResult |
| Sema::ActOnContinueStmt(SourceLocation ContinueLoc, Scope *CurScope) { |
| Scope *S = CurScope->getContinueParent(); |
| if (!S) { |
| // C99 6.8.6.2p1: A break shall appear only in or as a loop body. |
| return StmtError(Diag(ContinueLoc, diag::err_continue_not_in_loop)); |
| } |
| |
| return Owned(new (Context) ContinueStmt(ContinueLoc)); |
| } |
| |
| StmtResult |
| Sema::ActOnBreakStmt(SourceLocation BreakLoc, Scope *CurScope) { |
| Scope *S = CurScope->getBreakParent(); |
| if (!S) { |
| // C99 6.8.6.3p1: A break shall appear only in or as a switch/loop body. |
| return StmtError(Diag(BreakLoc, diag::err_break_not_in_loop_or_switch)); |
| } |
| |
| return Owned(new (Context) BreakStmt(BreakLoc)); |
| } |
| |
| /// \brief Determine whether the given expression is a candidate for |
| /// copy elision in either a return statement or a throw expression. |
| /// |
| /// \param ReturnType If we're determining the copy elision candidate for |
| /// a return statement, this is the return type of the function. If we're |
| /// determining the copy elision candidate for a throw expression, this will |
| /// be a NULL type. |
| /// |
| /// \param E The expression being returned from the function or block, or |
| /// being thrown. |
| /// |
| /// \param AllowFunctionParameter Whether we allow function parameters to |
| /// be considered NRVO candidates. C++ prohibits this for NRVO itself, but |
| /// we re-use this logic to determine whether we should try to move as part of |
| /// a return or throw (which does allow function parameters). |
| /// |
| /// \returns The NRVO candidate variable, if the return statement may use the |
| /// NRVO, or NULL if there is no such candidate. |
| const VarDecl *Sema::getCopyElisionCandidate(QualType ReturnType, |
| Expr *E, |
| bool AllowFunctionParameter) { |
| QualType ExprType = E->getType(); |
| // - in a return statement in a function with ... |
| // ... a class return type ... |
| if (!ReturnType.isNull()) { |
| if (!ReturnType->isRecordType()) |
| return 0; |
| // ... the same cv-unqualified type as the function return type ... |
| if (!Context.hasSameUnqualifiedType(ReturnType, ExprType)) |
| return 0; |
| } |
| |
| // ... the expression is the name of a non-volatile automatic object |
| // (other than a function or catch-clause parameter)) ... |
| const DeclRefExpr *DR = dyn_cast<DeclRefExpr>(E->IgnoreParens()); |
| if (!DR || DR->refersToEnclosingLocal()) |
| return 0; |
| const VarDecl *VD = dyn_cast<VarDecl>(DR->getDecl()); |
| if (!VD) |
| return 0; |
| |
| // ...object (other than a function or catch-clause parameter)... |
| if (VD->getKind() != Decl::Var && |
| !(AllowFunctionParameter && VD->getKind() == Decl::ParmVar)) |
| return 0; |
| if (VD->isExceptionVariable()) return 0; |
| |
| // ...automatic... |
| if (!VD->hasLocalStorage()) return 0; |
| |
| // ...non-volatile... |
| if (VD->getType().isVolatileQualified()) return 0; |
| if (VD->getType()->isReferenceType()) return 0; |
| |
| // __block variables can't be allocated in a way that permits NRVO. |
| if (VD->hasAttr<BlocksAttr>()) return 0; |
| |
| // Variables with higher required alignment than their type's ABI |
| // alignment cannot use NRVO. |
| if (VD->hasAttr<AlignedAttr>() && |
| Context.getDeclAlign(VD) > Context.getTypeAlignInChars(VD->getType())) |
| return 0; |
| |
| return VD; |
| } |
| |
| /// \brief Perform the initialization of a potentially-movable value, which |
| /// is the result of return value. |
| /// |
| /// This routine implements C++0x [class.copy]p33, which attempts to treat |
| /// returned lvalues as rvalues in certain cases (to prefer move construction), |
| /// then falls back to treating them as lvalues if that failed. |
| ExprResult |
| Sema::PerformMoveOrCopyInitialization(const InitializedEntity &Entity, |
| const VarDecl *NRVOCandidate, |
| QualType ResultType, |
| Expr *Value, |
| bool AllowNRVO) { |
| // C++0x [class.copy]p33: |
| // When the criteria for elision of a copy operation are met or would |
| // be met save for the fact that the source object is a function |
| // parameter, and the object to be copied is designated by an lvalue, |
| // overload resolution to select the constructor for the copy is first |
| // performed as if the object were designated by an rvalue. |
| ExprResult Res = ExprError(); |
| if (AllowNRVO && |
| (NRVOCandidate || getCopyElisionCandidate(ResultType, Value, true))) { |
| ImplicitCastExpr AsRvalue(ImplicitCastExpr::OnStack, |
| Value->getType(), CK_NoOp, Value, VK_XValue); |
| |
| Expr *InitExpr = &AsRvalue; |
| InitializationKind Kind |
| = InitializationKind::CreateCopy(Value->getLocStart(), |
| Value->getLocStart()); |
| InitializationSequence Seq(*this, Entity, Kind, InitExpr); |
| |
| // [...] If overload resolution fails, or if the type of the first |
| // parameter of the selected constructor is not an rvalue reference |
| // to the object's type (possibly cv-qualified), overload resolution |
| // is performed again, considering the object as an lvalue. |
| if (Seq) { |
| for (InitializationSequence::step_iterator Step = Seq.step_begin(), |
| StepEnd = Seq.step_end(); |
| Step != StepEnd; ++Step) { |
| if (Step->Kind != InitializationSequence::SK_ConstructorInitialization) |
| continue; |
| |
| CXXConstructorDecl *Constructor |
| = cast<CXXConstructorDecl>(Step->Function.Function); |
| |
| const RValueReferenceType *RRefType |
| = Constructor->getParamDecl(0)->getType() |
| ->getAs<RValueReferenceType>(); |
| |
| // If we don't meet the criteria, break out now. |
| if (!RRefType || |
| !Context.hasSameUnqualifiedType(RRefType->getPointeeType(), |
| Context.getTypeDeclType(Constructor->getParent()))) |
| break; |
| |
| // Promote "AsRvalue" to the heap, since we now need this |
| // expression node to persist. |
| Value = ImplicitCastExpr::Create(Context, Value->getType(), |
| CK_NoOp, Value, 0, VK_XValue); |
| |
| // Complete type-checking the initialization of the return type |
| // using the constructor we found. |
| Res = Seq.Perform(*this, Entity, Kind, Value); |
| } |
| } |
| } |
| |
| // Either we didn't meet the criteria for treating an lvalue as an rvalue, |
| // above, or overload resolution failed. Either way, we need to try |
| // (again) now with the return value expression as written. |
| if (Res.isInvalid()) |
| Res = PerformCopyInitialization(Entity, SourceLocation(), Value); |
| |
| return Res; |
| } |
| |
| /// \brief Determine whether the declared return type of the specified function |
| /// contains 'auto'. |
| static bool hasDeducedReturnType(FunctionDecl *FD) { |
| const FunctionProtoType *FPT = |
| FD->getTypeSourceInfo()->getType()->castAs<FunctionProtoType>(); |
| return FPT->getResultType()->isUndeducedType(); |
| } |
| |
| /// ActOnCapScopeReturnStmt - Utility routine to type-check return statements |
| /// for capturing scopes. |
| /// |
| StmtResult |
| Sema::ActOnCapScopeReturnStmt(SourceLocation ReturnLoc, Expr *RetValExp) { |
| // If this is the first return we've seen, infer the return type. |
| // [expr.prim.lambda]p4 in C++11; block literals follow the same rules. |
| CapturingScopeInfo *CurCap = cast<CapturingScopeInfo>(getCurFunction()); |
| QualType FnRetType = CurCap->ReturnType; |
| LambdaScopeInfo *CurLambda = dyn_cast<LambdaScopeInfo>(CurCap); |
| |
| if (CurLambda && hasDeducedReturnType(CurLambda->CallOperator)) { |
| // In C++1y, the return type may involve 'auto'. |
| // FIXME: Blocks might have a return type of 'auto' explicitly specified. |
| FunctionDecl *FD = CurLambda->CallOperator; |
| if (CurCap->ReturnType.isNull()) |
| CurCap->ReturnType = FD->getResultType(); |
| |
| AutoType *AT = CurCap->ReturnType->getContainedAutoType(); |
| assert(AT && "lost auto type from lambda return type"); |
| if (DeduceFunctionTypeFromReturnExpr(FD, ReturnLoc, RetValExp, AT)) { |
| FD->setInvalidDecl(); |
| return StmtError(); |
| } |
| CurCap->ReturnType = FnRetType = FD->getResultType(); |
| } else if (CurCap->HasImplicitReturnType) { |
| // For blocks/lambdas with implicit return types, we check each return |
| // statement individually, and deduce the common return type when the block |
| // or lambda is completed. |
| // FIXME: Fold this into the 'auto' codepath above. |
| if (RetValExp && !isa<InitListExpr>(RetValExp)) { |
| ExprResult Result = DefaultFunctionArrayLvalueConversion(RetValExp); |
| if (Result.isInvalid()) |
| return StmtError(); |
| RetValExp = Result.take(); |
| |
| if (!CurContext->isDependentContext()) |
| FnRetType = RetValExp->getType(); |
| else |
| FnRetType = CurCap->ReturnType = Context.DependentTy; |
| } else { |
| if (RetValExp) { |
| // C++11 [expr.lambda.prim]p4 bans inferring the result from an |
| // initializer list, because it is not an expression (even |
| // though we represent it as one). We still deduce 'void'. |
| Diag(ReturnLoc, diag::err_lambda_return_init_list) |
| << RetValExp->getSourceRange(); |
| } |
| |
| FnRetType = Context.VoidTy; |
| } |
| |
| // Although we'll properly infer the type of the block once it's completed, |
| // make sure we provide a return type now for better error recovery. |
| if (CurCap->ReturnType.isNull()) |
| CurCap->ReturnType = FnRetType; |
| } |
| assert(!FnRetType.isNull()); |
| |
| if (BlockScopeInfo *CurBlock = dyn_cast<BlockScopeInfo>(CurCap)) { |
| if (CurBlock->FunctionType->getAs<FunctionType>()->getNoReturnAttr()) { |
| Diag(ReturnLoc, diag::err_noreturn_block_has_return_expr); |
| return StmtError(); |
| } |
| } else if (CapturedRegionScopeInfo *CurRegion = |
| dyn_cast<CapturedRegionScopeInfo>(CurCap)) { |
| Diag(ReturnLoc, diag::err_return_in_captured_stmt) << CurRegion->getRegionName(); |
| return StmtError(); |
| } else { |
| assert(CurLambda && "unknown kind of captured scope"); |
| if (CurLambda->CallOperator->getType()->getAs<FunctionType>() |
| ->getNoReturnAttr()) { |
| Diag(ReturnLoc, diag::err_noreturn_lambda_has_return_expr); |
| return StmtError(); |
| } |
| } |
| |
| // Otherwise, verify that this result type matches the previous one. We are |
| // pickier with blocks than for normal functions because we don't have GCC |
| // compatibility to worry about here. |
| const VarDecl *NRVOCandidate = 0; |
| if (FnRetType->isDependentType()) { |
| // Delay processing for now. TODO: there are lots of dependent |
| // types we can conclusively prove aren't void. |
| } else if (FnRetType->isVoidType()) { |
| if (RetValExp && !isa<InitListExpr>(RetValExp) && |
| !(getLangOpts().CPlusPlus && |
| (RetValExp->isTypeDependent() || |
| RetValExp->getType()->isVoidType()))) { |
| if (!getLangOpts().CPlusPlus && |
| RetValExp->getType()->isVoidType()) |
| Diag(ReturnLoc, diag::ext_return_has_void_expr) << "literal" << 2; |
| else { |
| Diag(ReturnLoc, diag::err_return_block_has_expr); |
| RetValExp = 0; |
| } |
| } |
| } else if (!RetValExp) { |
| return StmtError(Diag(ReturnLoc, diag::err_block_return_missing_expr)); |
| } else if (!RetValExp->isTypeDependent()) { |
| // we have a non-void block with an expression, continue checking |
| |
| // C99 6.8.6.4p3(136): The return statement is not an assignment. The |
| // overlap restriction of subclause 6.5.16.1 does not apply to the case of |
| // function return. |
| |
| // In C++ the return statement is handled via a copy initialization. |
| // the C version of which boils down to CheckSingleAssignmentConstraints. |
| NRVOCandidate = getCopyElisionCandidate(FnRetType, RetValExp, false); |
| InitializedEntity Entity = InitializedEntity::InitializeResult(ReturnLoc, |
| FnRetType, |
| NRVOCandidate != 0); |
| ExprResult Res = PerformMoveOrCopyInitialization(Entity, NRVOCandidate, |
| FnRetType, RetValExp); |
| if (Res.isInvalid()) { |
| // FIXME: Cleanup temporaries here, anyway? |
| return StmtError(); |
| } |
| RetValExp = Res.take(); |
| CheckReturnStackAddr(RetValExp, FnRetType, ReturnLoc); |
| } |
| |
| if (RetValExp) { |
| ExprResult ER = ActOnFinishFullExpr(RetValExp, ReturnLoc); |
| if (ER.isInvalid()) |
| return StmtError(); |
| RetValExp = ER.take(); |
| } |
| ReturnStmt *Result = new (Context) ReturnStmt(ReturnLoc, RetValExp, |
| NRVOCandidate); |
| |
| // If we need to check for the named return value optimization, |
| // or if we need to infer the return type, |
| // save the return statement in our scope for later processing. |
| if (CurCap->HasImplicitReturnType || |
| (getLangOpts().CPlusPlus && FnRetType->isRecordType() && |
| !CurContext->isDependentContext())) |
| FunctionScopes.back()->Returns.push_back(Result); |
| |
| return Owned(Result); |
| } |
| |
| /// Deduce the return type for a function from a returned expression, per |
| /// C++1y [dcl.spec.auto]p6. |
| bool Sema::DeduceFunctionTypeFromReturnExpr(FunctionDecl *FD, |
| SourceLocation ReturnLoc, |
| Expr *&RetExpr, |
| AutoType *AT) { |
| TypeLoc OrigResultType = FD->getTypeSourceInfo()->getTypeLoc(). |
| IgnoreParens().castAs<FunctionProtoTypeLoc>().getResultLoc(); |
| QualType Deduced; |
| |
| if (RetExpr && isa<InitListExpr>(RetExpr)) { |
| // If the deduction is for a return statement and the initializer is |
| // a braced-init-list, the program is ill-formed. |
| Diag(RetExpr->getExprLoc(), |
| getCurLambda() ? diag::err_lambda_return_init_list |
| : diag::err_auto_fn_return_init_list) |
| << RetExpr->getSourceRange(); |
| return true; |
| } |
| |
| if (FD->isDependentContext()) { |
| // C++1y [dcl.spec.auto]p12: |
| // Return type deduction [...] occurs when the definition is |
| // instantiated even if the function body contains a return |
| // statement with a non-type-dependent operand. |
| assert(AT->isDeduced() && "should have deduced to dependent type"); |
| return false; |
| } else if (RetExpr) { |
| // If the deduction is for a return statement and the initializer is |
| // a braced-init-list, the program is ill-formed. |
| if (isa<InitListExpr>(RetExpr)) { |
| Diag(RetExpr->getExprLoc(), diag::err_auto_fn_return_init_list); |
| return true; |
| } |
| |
| // Otherwise, [...] deduce a value for U using the rules of template |
| // argument deduction. |
| DeduceAutoResult DAR = DeduceAutoType(OrigResultType, RetExpr, Deduced); |
| |
| if (DAR == DAR_Failed && !FD->isInvalidDecl()) |
| Diag(RetExpr->getExprLoc(), diag::err_auto_fn_deduction_failure) |
| << OrigResultType.getType() << RetExpr->getType(); |
| |
| if (DAR != DAR_Succeeded) |
| return true; |
| } else { |
| // In the case of a return with no operand, the initializer is considered |
| // to be void(). |
| // |
| // Deduction here can only succeed if the return type is exactly 'cv auto' |
| // or 'decltype(auto)', so just check for that case directly. |
| if (!OrigResultType.getType()->getAs<AutoType>()) { |
| Diag(ReturnLoc, diag::err_auto_fn_return_void_but_not_auto) |
| << OrigResultType.getType(); |
| return true; |
| } |
| // We always deduce U = void in this case. |
| Deduced = SubstAutoType(OrigResultType.getType(), Context.VoidTy); |
| if (Deduced.isNull()) |
| return true; |
| } |
| |
| // If a function with a declared return type that contains a placeholder type |
| // has multiple return statements, the return type is deduced for each return |
| // statement. [...] if the type deduced is not the same in each deduction, |
| // the program is ill-formed. |
| if (AT->isDeduced() && !FD->isInvalidDecl()) { |
| AutoType *NewAT = Deduced->getContainedAutoType(); |
| if (!FD->isDependentContext() && |
| !Context.hasSameType(AT->getDeducedType(), NewAT->getDeducedType())) { |
| const LambdaScopeInfo *LambdaSI = getCurLambda(); |
| if (LambdaSI && LambdaSI->HasImplicitReturnType) { |
| Diag(ReturnLoc, diag::err_typecheck_missing_return_type_incompatible) |
| << NewAT->getDeducedType() << AT->getDeducedType() |
| << true /*IsLambda*/; |
| } else { |
| Diag(ReturnLoc, diag::err_auto_fn_different_deductions) |
| << (AT->isDecltypeAuto() ? 1 : 0) |
| << NewAT->getDeducedType() << AT->getDeducedType(); |
| } |
| return true; |
| } |
| } else if (!FD->isInvalidDecl()) { |
| // Update all declarations of the function to have the deduced return type. |
| Context.adjustDeducedFunctionResultType(FD, Deduced); |
| } |
| |
| return false; |
| } |
| |
| StmtResult |
| Sema::ActOnReturnStmt(SourceLocation ReturnLoc, Expr *RetValExp) { |
| // Check for unexpanded parameter packs. |
| if (RetValExp && DiagnoseUnexpandedParameterPack(RetValExp)) |
| return StmtError(); |
| |
| if (isa<CapturingScopeInfo>(getCurFunction())) |
| return ActOnCapScopeReturnStmt(ReturnLoc, RetValExp); |
| |
| QualType FnRetType; |
| QualType RelatedRetType; |
| if (const FunctionDecl *FD = getCurFunctionDecl()) { |
| FnRetType = FD->getResultType(); |
| if (FD->isNoReturn()) |
| Diag(ReturnLoc, diag::warn_noreturn_function_has_return_expr) |
| << FD->getDeclName(); |
| } else if (ObjCMethodDecl *MD = getCurMethodDecl()) { |
| FnRetType = MD->getResultType(); |
| if (MD->hasRelatedResultType() && MD->getClassInterface()) { |
| // In the implementation of a method with a related return type, the |
| // type used to type-check the validity of return statements within the |
| // method body is a pointer to the type of the class being implemented. |
| RelatedRetType = Context.getObjCInterfaceType(MD->getClassInterface()); |
| RelatedRetType = Context.getObjCObjectPointerType(RelatedRetType); |
| } |
| } else // If we don't have a function/method context, bail. |
| return StmtError(); |
| |
| // FIXME: Add a flag to the ScopeInfo to indicate whether we're performing |
| // deduction. |
| if (getLangOpts().CPlusPlus1y) { |
| if (AutoType *AT = FnRetType->getContainedAutoType()) { |
| FunctionDecl *FD = cast<FunctionDecl>(CurContext); |
| if (DeduceFunctionTypeFromReturnExpr(FD, ReturnLoc, RetValExp, AT)) { |
| FD->setInvalidDecl(); |
| return StmtError(); |
| } else { |
| FnRetType = FD->getResultType(); |
| } |
| } |
| } |
| |
| bool HasDependentReturnType = FnRetType->isDependentType(); |
| |
| ReturnStmt *Result = 0; |
| if (FnRetType->isVoidType()) { |
| if (RetValExp) { |
| if (isa<InitListExpr>(RetValExp)) { |
| // We simply never allow init lists as the return value of void |
| // functions. This is compatible because this was never allowed before, |
| // so there's no legacy code to deal with. |
| NamedDecl *CurDecl = getCurFunctionOrMethodDecl(); |
| int FunctionKind = 0; |
| if (isa<ObjCMethodDecl>(CurDecl)) |
| FunctionKind = 1; |
| else if (isa<CXXConstructorDecl>(CurDecl)) |
| FunctionKind = 2; |
| else if (isa<CXXDestructorDecl>(CurDecl)) |
| FunctionKind = 3; |
| |
| Diag(ReturnLoc, diag::err_return_init_list) |
| << CurDecl->getDeclName() << FunctionKind |
| << RetValExp->getSourceRange(); |
| |
| // Drop the expression. |
| RetValExp = 0; |
| } else if (!RetValExp->isTypeDependent()) { |
| // C99 6.8.6.4p1 (ext_ since GCC warns) |
| unsigned D = diag::ext_return_has_expr; |
| if (RetValExp->getType()->isVoidType()) |
| D = diag::ext_return_has_void_expr; |
| else { |
| ExprResult Result = Owned(RetValExp); |
| Result = IgnoredValueConversions(Result.take()); |
| if (Result.isInvalid()) |
| return StmtError(); |
| RetValExp = Result.take(); |
| RetValExp = ImpCastExprToType(RetValExp, |
| Context.VoidTy, CK_ToVoid).take(); |
| } |
| |
| // return (some void expression); is legal in C++. |
| if (D != diag::ext_return_has_void_expr || |
| !getLangOpts().CPlusPlus) { |
| NamedDecl *CurDecl = getCurFunctionOrMethodDecl(); |
| |
| int FunctionKind = 0; |
| if (isa<ObjCMethodDecl>(CurDecl)) |
| FunctionKind = 1; |
| else if (isa<CXXConstructorDecl>(CurDecl)) |
| FunctionKind = 2; |
| else if (isa<CXXDestructorDecl>(CurDecl)) |
| FunctionKind = 3; |
| |
| Diag(ReturnLoc, D) |
| << CurDecl->getDeclName() << FunctionKind |
| << RetValExp->getSourceRange(); |
| } |
| } |
| |
| if (RetValExp) { |
| ExprResult ER = ActOnFinishFullExpr(RetValExp, ReturnLoc); |
| if (ER.isInvalid()) |
| return StmtError(); |
| RetValExp = ER.take(); |
| } |
| } |
| |
| Result = new (Context) ReturnStmt(ReturnLoc, RetValExp, 0); |
| } else if (!RetValExp && !HasDependentReturnType) { |
| unsigned DiagID = diag::warn_return_missing_expr; // C90 6.6.6.4p4 |
| // C99 6.8.6.4p1 (ext_ since GCC warns) |
| if (getLangOpts().C99) DiagID = diag::ext_return_missing_expr; |
| |
| if (FunctionDecl *FD = getCurFunctionDecl()) |
| Diag(ReturnLoc, DiagID) << FD->getIdentifier() << 0/*fn*/; |
| else |
| Diag(ReturnLoc, DiagID) << getCurMethodDecl()->getDeclName() << 1/*meth*/; |
| Result = new (Context) ReturnStmt(ReturnLoc); |
| } else { |
| assert(RetValExp || HasDependentReturnType); |
| const VarDecl *NRVOCandidate = 0; |
| if (!HasDependentReturnType && !RetValExp->isTypeDependent()) { |
| // we have a non-void function with an expression, continue checking |
| |
| QualType RetType = (RelatedRetType.isNull() ? FnRetType : RelatedRetType); |
| |
| // C99 6.8.6.4p3(136): The return statement is not an assignment. The |
| // overlap restriction of subclause 6.5.16.1 does not apply to the case of |
| // function return. |
| |
| // In C++ the return statement is handled via a copy initialization, |
| // the C version of which boils down to CheckSingleAssignmentConstraints. |
| NRVOCandidate = getCopyElisionCandidate(FnRetType, RetValExp, false); |
| InitializedEntity Entity = InitializedEntity::InitializeResult(ReturnLoc, |
| RetType, |
| NRVOCandidate != 0); |
| ExprResult Res = PerformMoveOrCopyInitialization(Entity, NRVOCandidate, |
| RetType, RetValExp); |
| if (Res.isInvalid()) { |
| // FIXME: Clean up temporaries here anyway? |
| return StmtError(); |
| } |
| RetValExp = Res.takeAs<Expr>(); |
| |
| // If we have a related result type, we need to implicitly |
| // convert back to the formal result type. We can't pretend to |
| // initialize the result again --- we might end double-retaining |
| // --- so instead we initialize a notional temporary. |
| if (!RelatedRetType.isNull()) { |
| Entity = InitializedEntity::InitializeRelatedResult(getCurMethodDecl(), |
| FnRetType); |
| Res = PerformCopyInitialization(Entity, ReturnLoc, RetValExp); |
| if (Res.isInvalid()) { |
| // FIXME: Clean up temporaries here anyway? |
| return StmtError(); |
| } |
| RetValExp = Res.takeAs<Expr>(); |
| } |
| |
| CheckReturnStackAddr(RetValExp, FnRetType, ReturnLoc); |
| } |
| |
| if (RetValExp) { |
| ExprResult ER = ActOnFinishFullExpr(RetValExp, ReturnLoc); |
| if (ER.isInvalid()) |
| return StmtError(); |
| RetValExp = ER.take(); |
| } |
| Result = new (Context) ReturnStmt(ReturnLoc, RetValExp, NRVOCandidate); |
| } |
| |
| // If we need to check for the named return value optimization, save the |
| // return statement in our scope for later processing. |
| if (getLangOpts().CPlusPlus && FnRetType->isRecordType() && |
| !CurContext->isDependentContext()) |
| FunctionScopes.back()->Returns.push_back(Result); |
| |
| return Owned(Result); |
| } |
| |
| StmtResult |
| Sema::ActOnObjCAtCatchStmt(SourceLocation AtLoc, |
| SourceLocation RParen, Decl *Parm, |
| Stmt *Body) { |
| VarDecl *Var = cast_or_null<VarDecl>(Parm); |
| if (Var && Var->isInvalidDecl()) |
| return StmtError(); |
| |
| return Owned(new (Context) ObjCAtCatchStmt(AtLoc, RParen, Var, Body)); |
| } |
| |
| StmtResult |
| Sema::ActOnObjCAtFinallyStmt(SourceLocation AtLoc, Stmt *Body) { |
| return Owned(new (Context) ObjCAtFinallyStmt(AtLoc, Body)); |
| } |
| |
| StmtResult |
| Sema::ActOnObjCAtTryStmt(SourceLocation AtLoc, Stmt *Try, |
| MultiStmtArg CatchStmts, Stmt *Finally) { |
| if (!getLangOpts().ObjCExceptions) |
| Diag(AtLoc, diag::err_objc_exceptions_disabled) << "@try"; |
| |
| getCurFunction()->setHasBranchProtectedScope(); |
| unsigned NumCatchStmts = CatchStmts.size(); |
| return Owned(ObjCAtTryStmt::Create(Context, AtLoc, Try, |
| CatchStmts.data(), |
| NumCatchStmts, |
| Finally)); |
| } |
| |
| StmtResult Sema::BuildObjCAtThrowStmt(SourceLocation AtLoc, Expr *Throw) { |
| if (Throw) { |
| ExprResult Result = DefaultLvalueConversion(Throw); |
| if (Result.isInvalid()) |
| return StmtError(); |
| |
| Result = ActOnFinishFullExpr(Result.take()); |
| if (Result.isInvalid()) |
| return StmtError(); |
| Throw = Result.take(); |
| |
| QualType ThrowType = Throw->getType(); |
| // Make sure the expression type is an ObjC pointer or "void *". |
| if (!ThrowType->isDependentType() && |
| !ThrowType->isObjCObjectPointerType()) { |
| const PointerType *PT = ThrowType->getAs<PointerType>(); |
| if (!PT || !PT->getPointeeType()->isVoidType()) |
| return StmtError(Diag(AtLoc, diag::error_objc_throw_expects_object) |
| << Throw->getType() << Throw->getSourceRange()); |
| } |
| } |
| |
| return Owned(new (Context) ObjCAtThrowStmt(AtLoc, Throw)); |
| } |
| |
| StmtResult |
| Sema::ActOnObjCAtThrowStmt(SourceLocation AtLoc, Expr *Throw, |
| Scope *CurScope) { |
| if (!getLangOpts().ObjCExceptions) |
| Diag(AtLoc, diag::err_objc_exceptions_disabled) << "@throw"; |
| |
| if (!Throw) { |
| // @throw without an expression designates a rethrow (which much occur |
| // in the context of an @catch clause). |
| Scope *AtCatchParent = CurScope; |
| while (AtCatchParent && !AtCatchParent->isAtCatchScope()) |
| AtCatchParent = AtCatchParent->getParent(); |
| if (!AtCatchParent) |
| return StmtError(Diag(AtLoc, diag::error_rethrow_used_outside_catch)); |
| } |
| return BuildObjCAtThrowStmt(AtLoc, Throw); |
| } |
| |
| ExprResult |
| Sema::ActOnObjCAtSynchronizedOperand(SourceLocation atLoc, Expr *operand) { |
| ExprResult result = DefaultLvalueConversion(operand); |
| if (result.isInvalid()) |
| return ExprError(); |
| operand = result.take(); |
| |
| // Make sure the expression type is an ObjC pointer or "void *". |
| QualType type = operand->getType(); |
| if (!type->isDependentType() && |
| !type->isObjCObjectPointerType()) { |
| const PointerType *pointerType = type->getAs<PointerType>(); |
| if (!pointerType || !pointerType->getPointeeType()->isVoidType()) |
| return Diag(atLoc, diag::error_objc_synchronized_expects_object) |
| << type << operand->getSourceRange(); |
| } |
| |
| // The operand to @synchronized is a full-expression. |
| return ActOnFinishFullExpr(operand); |
| } |
| |
| StmtResult |
| Sema::ActOnObjCAtSynchronizedStmt(SourceLocation AtLoc, Expr *SyncExpr, |
| Stmt *SyncBody) { |
| // We can't jump into or indirect-jump out of a @synchronized block. |
| getCurFunction()->setHasBranchProtectedScope(); |
| return Owned(new (Context) ObjCAtSynchronizedStmt(AtLoc, SyncExpr, SyncBody)); |
| } |
| |
| /// ActOnCXXCatchBlock - Takes an exception declaration and a handler block |
| /// and creates a proper catch handler from them. |
| StmtResult |
| Sema::ActOnCXXCatchBlock(SourceLocation CatchLoc, Decl *ExDecl, |
| Stmt *HandlerBlock) { |
| // There's nothing to test that ActOnExceptionDecl didn't already test. |
| return Owned(new (Context) CXXCatchStmt(CatchLoc, |
| cast_or_null<VarDecl>(ExDecl), |
| HandlerBlock)); |
| } |
| |
| StmtResult |
| Sema::ActOnObjCAutoreleasePoolStmt(SourceLocation AtLoc, Stmt *Body) { |
| getCurFunction()->setHasBranchProtectedScope(); |
| return Owned(new (Context) ObjCAutoreleasePoolStmt(AtLoc, Body)); |
| } |
| |
| namespace { |
| |
| class TypeWithHandler { |
| QualType t; |
| CXXCatchStmt *stmt; |
| public: |
| TypeWithHandler(const QualType &type, CXXCatchStmt *statement) |
| : t(type), stmt(statement) {} |
| |
| // An arbitrary order is fine as long as it places identical |
| // types next to each other. |
| bool operator<(const TypeWithHandler &y) const { |
| if (t.getAsOpaquePtr() < y.t.getAsOpaquePtr()) |
| return true; |
| if (t.getAsOpaquePtr() > y.t.getAsOpaquePtr()) |
| return false; |
| else |
| return getTypeSpecStartLoc() < y.getTypeSpecStartLoc(); |
| } |
| |
| bool operator==(const TypeWithHandler& other) const { |
| return t == other.t; |
| } |
| |
| CXXCatchStmt *getCatchStmt() const { return stmt; } |
| SourceLocation getTypeSpecStartLoc() const { |
| return stmt->getExceptionDecl()->getTypeSpecStartLoc(); |
| } |
| }; |
| |
| } |
| |
| /// ActOnCXXTryBlock - Takes a try compound-statement and a number of |
| /// handlers and creates a try statement from them. |
| StmtResult Sema::ActOnCXXTryBlock(SourceLocation TryLoc, Stmt *TryBlock, |
| ArrayRef<Stmt *> Handlers) { |
| // Don't report an error if 'try' is used in system headers. |
| if (!getLangOpts().CXXExceptions && |
| !getSourceManager().isInSystemHeader(TryLoc)) |
| Diag(TryLoc, diag::err_exceptions_disabled) << "try"; |
| |
| const unsigned NumHandlers = Handlers.size(); |
| assert(NumHandlers > 0 && |
| "The parser shouldn't call this if there are no handlers."); |
| |
| SmallVector<TypeWithHandler, 8> TypesWithHandlers; |
| |
| for (unsigned i = 0; i < NumHandlers; ++i) { |
| CXXCatchStmt *Handler = cast<CXXCatchStmt>(Handlers[i]); |
| if (!Handler->getExceptionDecl()) { |
| if (i < NumHandlers - 1) |
| return StmtError(Diag(Handler->getLocStart(), |
| diag::err_early_catch_all)); |
| |
| continue; |
| } |
| |
| const QualType CaughtType = Handler->getCaughtType(); |
| const QualType CanonicalCaughtType = Context.getCanonicalType(CaughtType); |
| TypesWithHandlers.push_back(TypeWithHandler(CanonicalCaughtType, Handler)); |
| } |
| |
| // Detect handlers for the same type as an earlier one. |
| if (NumHandlers > 1) { |
| llvm::array_pod_sort(TypesWithHandlers.begin(), TypesWithHandlers.end()); |
| |
| TypeWithHandler prev = TypesWithHandlers[0]; |
| for (unsigned i = 1; i < TypesWithHandlers.size(); ++i) { |
| TypeWithHandler curr = TypesWithHandlers[i]; |
| |
| if (curr == prev) { |
| Diag(curr.getTypeSpecStartLoc(), |
| diag::warn_exception_caught_by_earlier_handler) |
| << curr.getCatchStmt()->getCaughtType().getAsString(); |
| Diag(prev.getTypeSpecStartLoc(), |
| diag::note_previous_exception_handler) |
| << prev.getCatchStmt()->getCaughtType().getAsString(); |
| } |
| |
| prev = curr; |
| } |
| } |
| |
| getCurFunction()->setHasBranchProtectedScope(); |
| |
| // FIXME: We should detect handlers that cannot catch anything because an |
| // earlier handler catches a superclass. Need to find a method that is not |
| // quadratic for this. |
| // Neither of these are explicitly forbidden, but every compiler detects them |
| // and warns. |
| |
| return Owned(CXXTryStmt::Create(Context, TryLoc, TryBlock, Handlers)); |
| } |
| |
| StmtResult |
| Sema::ActOnSEHTryBlock(bool IsCXXTry, |
| SourceLocation TryLoc, |
| Stmt *TryBlock, |
| Stmt *Handler) { |
| assert(TryBlock && Handler); |
| |
| getCurFunction()->setHasBranchProtectedScope(); |
| |
| return Owned(SEHTryStmt::Create(Context,IsCXXTry,TryLoc,TryBlock,Handler)); |
| } |
| |
| StmtResult |
| Sema::ActOnSEHExceptBlock(SourceLocation Loc, |
| Expr *FilterExpr, |
| Stmt *Block) { |
| assert(FilterExpr && Block); |
| |
| if(!FilterExpr->getType()->isIntegerType()) { |
| return StmtError(Diag(FilterExpr->getExprLoc(), |
| diag::err_filter_expression_integral) |
| << FilterExpr->getType()); |
| } |
| |
| return Owned(SEHExceptStmt::Create(Context,Loc,FilterExpr,Block)); |
| } |
| |
| StmtResult |
| Sema::ActOnSEHFinallyBlock(SourceLocation Loc, |
| Stmt *Block) { |
| assert(Block); |
| return Owned(SEHFinallyStmt::Create(Context,Loc,Block)); |
| } |
| |
| StmtResult Sema::BuildMSDependentExistsStmt(SourceLocation KeywordLoc, |
| bool IsIfExists, |
| NestedNameSpecifierLoc QualifierLoc, |
| DeclarationNameInfo NameInfo, |
| Stmt *Nested) |
| { |
| return new (Context) MSDependentExistsStmt(KeywordLoc, IsIfExists, |
| QualifierLoc, NameInfo, |
| cast<CompoundStmt>(Nested)); |
| } |
| |
| |
| StmtResult Sema::ActOnMSDependentExistsStmt(SourceLocation KeywordLoc, |
| bool IsIfExists, |
| CXXScopeSpec &SS, |
| UnqualifiedId &Name, |
| Stmt *Nested) { |
| return BuildMSDependentExistsStmt(KeywordLoc, IsIfExists, |
| SS.getWithLocInContext(Context), |
| GetNameFromUnqualifiedId(Name), |
| Nested); |
| } |
| |
| RecordDecl* |
| Sema::CreateCapturedStmtRecordDecl(CapturedDecl *&CD, SourceLocation Loc, |
| unsigned NumParams) { |
| DeclContext *DC = CurContext; |
| while (!(DC->isFunctionOrMethod() || DC->isRecord() || DC->isFileContext())) |
| DC = DC->getParent(); |
| |
| RecordDecl *RD = 0; |
| if (getLangOpts().CPlusPlus) |
| RD = CXXRecordDecl::Create(Context, TTK_Struct, DC, Loc, Loc, /*Id=*/0); |
| else |
| RD = RecordDecl::Create(Context, TTK_Struct, DC, Loc, Loc, /*Id=*/0); |
| |
| DC->addDecl(RD); |
| RD->setImplicit(); |
| RD->startDefinition(); |
| |
| CD = CapturedDecl::Create(Context, CurContext, NumParams); |
| DC->addDecl(CD); |
| |
| // Build the context parameter |
| assert(NumParams > 0 && "CapturedStmt requires context parameter"); |
| DC = CapturedDecl::castToDeclContext(CD); |
| IdentifierInfo *VarName = &Context.Idents.get("__context"); |
| QualType ParamType = Context.getPointerType(Context.getTagDeclType(RD)); |
| ImplicitParamDecl *Param |
| = ImplicitParamDecl::Create(Context, DC, Loc, VarName, ParamType); |
| DC->addDecl(Param); |
| |
| CD->setContextParam(Param); |
| |
| return RD; |
| } |
| |
| static void buildCapturedStmtCaptureList( |
| SmallVectorImpl<CapturedStmt::Capture> &Captures, |
| SmallVectorImpl<Expr *> &CaptureInits, |
| ArrayRef<CapturingScopeInfo::Capture> Candidates) { |
| |
| typedef ArrayRef<CapturingScopeInfo::Capture>::const_iterator CaptureIter; |
| for (CaptureIter Cap = Candidates.begin(); Cap != Candidates.end(); ++Cap) { |
| |
| if (Cap->isThisCapture()) { |
| Captures.push_back(CapturedStmt::Capture(Cap->getLocation(), |
| CapturedStmt::VCK_This)); |
| CaptureInits.push_back(Cap->getInitExpr()); |
| continue; |
| } |
| |
| assert(Cap->isReferenceCapture() && |
| "non-reference capture not yet implemented"); |
| |
| Captures.push_back(CapturedStmt::Capture(Cap->getLocation(), |
| CapturedStmt::VCK_ByRef, |
| Cap->getVariable())); |
| CaptureInits.push_back(Cap->getInitExpr()); |
| } |
| } |
| |
| void Sema::ActOnCapturedRegionStart(SourceLocation Loc, Scope *CurScope, |
| CapturedRegionKind Kind, |
| unsigned NumParams) { |
| CapturedDecl *CD = 0; |
| RecordDecl *RD = CreateCapturedStmtRecordDecl(CD, Loc, NumParams); |
| |
| // Enter the capturing scope for this captured region. |
| PushCapturedRegionScope(CurScope, CD, RD, Kind); |
| |
| if (CurScope) |
| PushDeclContext(CurScope, CD); |
| else |
| CurContext = CD; |
| |
| PushExpressionEvaluationContext(PotentiallyEvaluated); |
| } |
| |
| void Sema::ActOnCapturedRegionError() { |
| DiscardCleanupsInEvaluationContext(); |
| PopExpressionEvaluationContext(); |
| |
| CapturedRegionScopeInfo *RSI = getCurCapturedRegion(); |
| RecordDecl *Record = RSI->TheRecordDecl; |
| Record->setInvalidDecl(); |
| |
| SmallVector<Decl*, 4> Fields; |
| for (RecordDecl::field_iterator I = Record->field_begin(), |
| E = Record->field_end(); I != E; ++I) |
| Fields.push_back(*I); |
| ActOnFields(/*Scope=*/0, Record->getLocation(), Record, Fields, |
| SourceLocation(), SourceLocation(), /*AttributeList=*/0); |
| |
| PopDeclContext(); |
| PopFunctionScopeInfo(); |
| } |
| |
| StmtResult Sema::ActOnCapturedRegionEnd(Stmt *S) { |
| CapturedRegionScopeInfo *RSI = getCurCapturedRegion(); |
| |
| SmallVector<CapturedStmt::Capture, 4> Captures; |
| SmallVector<Expr *, 4> CaptureInits; |
| buildCapturedStmtCaptureList(Captures, CaptureInits, RSI->Captures); |
| |
| CapturedDecl *CD = RSI->TheCapturedDecl; |
| RecordDecl *RD = RSI->TheRecordDecl; |
| |
| CapturedStmt *Res = CapturedStmt::Create(getASTContext(), S, |
| RSI->CapRegionKind, Captures, |
| CaptureInits, CD, RD); |
| |
| CD->setBody(Res->getCapturedStmt()); |
| RD->completeDefinition(); |
| |
| DiscardCleanupsInEvaluationContext(); |
| PopExpressionEvaluationContext(); |
| |
| PopDeclContext(); |
| PopFunctionScopeInfo(); |
| |
| return Owned(Res); |
| } |