Delete CC_Default and use the target default CC everywhere
Summary:
Makes functions with implicit calling convention compatible with
function types with a matching explicit calling convention. This fixes
things like calls to qsort(), which has an explicit __cdecl attribute on
the comparator in Windows headers.
Clang will now infer the calling convention from the declarator. There
are two cases when the CC must be adjusted during redeclaration:
1. When defining a non-inline static method.
2. When redeclaring a function with an implicit or mismatched
convention.
Fixes PR13457, and allows clang to compile CommandLine.cpp for the
Microsoft C++ ABI.
Excellent test cases provided by Alexander Zinenko!
Reviewers: rsmith
Differential Revision: http://llvm-reviews.chandlerc.com/D1231
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@189412 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index d831c70..748814d 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -2201,17 +2201,11 @@
FD->getStorageClass() == SC_Extern);
}
-/// Is the given calling convention the ABI default for the given
-/// declaration?
-static bool isABIDefaultCC(Sema &S, CallingConv CC, FunctionDecl *D) {
- CallingConv ABIDefaultCC;
- if (isa<CXXMethodDecl>(D) && cast<CXXMethodDecl>(D)->isInstance()) {
- ABIDefaultCC = S.Context.getDefaultCXXMethodCallConv(D->isVariadic());
- } else {
- // Free C function or a static method.
- ABIDefaultCC = (S.Context.getLangOpts().MRTD ? CC_X86StdCall : CC_C);
- }
- return ABIDefaultCC == CC;
+const AttributedType *Sema::getCallingConvAttributedType(QualType T) const {
+ const AttributedType *AT = T->getAs<AttributedType>();
+ while (AT && !AT->isCallingConv())
+ AT = AT->getModifiedType()->getAs<AttributedType>();
+ return AT;
}
template <typename T>
@@ -2287,9 +2281,6 @@
else
PrevDiag = diag::note_previous_declaration;
- QualType OldQType = Context.getCanonicalType(Old->getType());
- QualType NewQType = Context.getCanonicalType(New->getType());
-
// Don't complain about this if we're in GNU89 mode and the old function
// is an extern inline function.
// Don't complain about specializations. They are not supposed to have
@@ -2309,53 +2300,52 @@
}
}
- // If a function is first declared with a calling convention, but is
- // later declared or defined without one, the second decl assumes the
- // calling convention of the first.
+
+ // If a function is first declared with a calling convention, but is later
+ // declared or defined without one, all following decls assume the calling
+ // convention of the first.
//
// It's OK if a function is first declared without a calling convention,
// but is later declared or defined with the default calling convention.
//
- // For the new decl, we have to look at the NON-canonical type to tell the
- // difference between a function that really doesn't have a calling
- // convention and one that is declared cdecl. That's because in
- // canonicalization (see ASTContext.cpp), cdecl is canonicalized away
- // because it is the default calling convention.
+ // To test if either decl has an explicit calling convention, we look for
+ // AttributedType sugar nodes on the type as written. If they are missing or
+ // were canonicalized away, we assume the calling convention was implicit.
//
// Note also that we DO NOT return at this point, because we still have
// other tests to run.
+ QualType OldQType = Context.getCanonicalType(Old->getType());
+ QualType NewQType = Context.getCanonicalType(New->getType());
const FunctionType *OldType = cast<FunctionType>(OldQType);
- const FunctionType *NewType = New->getType()->getAs<FunctionType>();
+ const FunctionType *NewType = cast<FunctionType>(NewQType);
FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo();
FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo();
bool RequiresAdjustment = false;
- if (OldTypeInfo.getCC() == NewTypeInfo.getCC()) {
- // Fast path: nothing to do.
- // Inherit the CC from the previous declaration if it was specified
- // there but not here.
- } else if (NewTypeInfo.getCC() == CC_Default) {
- NewTypeInfo = NewTypeInfo.withCallingConv(OldTypeInfo.getCC());
- RequiresAdjustment = true;
+ if (OldTypeInfo.getCC() != NewTypeInfo.getCC()) {
+ FunctionDecl *First = Old->getFirstDeclaration();
+ const FunctionType *FT =
+ First->getType().getCanonicalType()->castAs<FunctionType>();
+ FunctionType::ExtInfo FI = FT->getExtInfo();
+ bool NewCCExplicit = getCallingConvAttributedType(New->getType());
+ if (!NewCCExplicit) {
+ // Inherit the CC from the previous declaration if it was specified
+ // there but not here.
+ NewTypeInfo = NewTypeInfo.withCallingConv(OldTypeInfo.getCC());
+ RequiresAdjustment = true;
+ } else {
+ // Calling conventions aren't compatible, so complain.
+ bool FirstCCExplicit = getCallingConvAttributedType(First->getType());
+ Diag(New->getLocation(), diag::err_cconv_change)
+ << FunctionType::getNameForCallConv(NewTypeInfo.getCC())
+ << !FirstCCExplicit
+ << (!FirstCCExplicit ? "" :
+ FunctionType::getNameForCallConv(FI.getCC()));
- // Don't complain about mismatches when the default CC is
- // effectively the same as the explict one. Only Old decl contains correct
- // information about storage class of CXXMethod.
- } else if (OldTypeInfo.getCC() == CC_Default &&
- isABIDefaultCC(*this, NewTypeInfo.getCC(), Old)) {
- NewTypeInfo = NewTypeInfo.withCallingConv(OldTypeInfo.getCC());
- RequiresAdjustment = true;
-
- } else if (!Context.isSameCallConv(OldTypeInfo.getCC(),
- NewTypeInfo.getCC())) {
- // Calling conventions really aren't compatible, so complain.
- Diag(New->getLocation(), diag::err_cconv_change)
- << FunctionType::getNameForCallConv(NewTypeInfo.getCC())
- << (OldTypeInfo.getCC() == CC_Default)
- << (OldTypeInfo.getCC() == CC_Default ? "" :
- FunctionType::getNameForCallConv(OldTypeInfo.getCC()));
- Diag(Old->getLocation(), diag::note_previous_declaration);
- return true;
+ // Put the note on the first decl, since it is the one that matters.
+ Diag(First->getLocation(), diag::note_previous_declaration);
+ return true;
+ }
}
// FIXME: diagnose the other way around?
@@ -6463,6 +6453,11 @@
diag::err_invalid_thread)
<< DeclSpec::getSpecifierName(TSCS);
+ if (DC->isRecord() &&
+ D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static &&
+ !D.getDeclSpec().isFriendSpecified())
+ adjustMemberFunctionCC(R);
+
bool isFriend = false;
FunctionTemplateDecl *FunctionTemplate = 0;
bool isExplicitSpecialization = false;
@@ -7144,7 +7139,8 @@
// Turn this into a variadic function with no parameters.
const FunctionType *FT = NewFD->getType()->getAs<FunctionType>();
- FunctionProtoType::ExtProtoInfo EPI;
+ FunctionProtoType::ExtProtoInfo EPI(
+ Context.getDefaultCallingConvention(true, false));
EPI.Variadic = true;
EPI.ExtInfo = FT->getExtInfo();
diff --git a/lib/Sema/SemaDeclCXX.cpp b/lib/Sema/SemaDeclCXX.cpp
index f12f923..bfb96c7 100644
--- a/lib/Sema/SemaDeclCXX.cpp
+++ b/lib/Sema/SemaDeclCXX.cpp
@@ -4435,6 +4435,21 @@
FPT->getArgTypes(), EPI));
}
+static FunctionProtoType::ExtProtoInfo getImplicitMethodEPI(Sema &S,
+ CXXMethodDecl *MD) {
+ FunctionProtoType::ExtProtoInfo EPI;
+
+ // Build an exception specification pointing back at this member.
+ EPI.ExceptionSpecType = EST_Unevaluated;
+ EPI.ExceptionSpecDecl = MD;
+
+ // Set the calling convention to the default for C++ instance methods.
+ EPI.ExtInfo = EPI.ExtInfo.withCallingConv(
+ S.Context.getDefaultCallingConvention(/*IsVariadic=*/false,
+ /*IsCXXMethod=*/true));
+ return EPI;
+}
+
void Sema::EvaluateImplicitExceptionSpec(SourceLocation Loc, CXXMethodDecl *MD) {
const FunctionProtoType *FPT = MD->getType()->castAs<FunctionProtoType>();
if (FPT->getExceptionSpecType() != EST_Unevaluated)
@@ -4631,7 +4646,9 @@
void Sema::CheckExplicitlyDefaultedMemberExceptionSpec(
CXXMethodDecl *MD, const FunctionProtoType *SpecifiedType) {
// Compute the implicit exception specification.
- FunctionProtoType::ExtProtoInfo EPI;
+ CallingConv CC = Context.getDefaultCallingConvention(/*IsVariadic=*/false,
+ /*IsCXXMethod=*/true);
+ FunctionProtoType::ExtProtoInfo EPI(CC);
computeImplicitExceptionSpec(*this, MD->getLocation(), MD).getEPI(EPI);
const FunctionProtoType *ImplicitType = cast<FunctionProtoType>(
Context.getFunctionType(Context.VoidTy, None, EPI));
@@ -7891,9 +7908,7 @@
DefaultCon->setImplicit();
// Build an exception specification pointing back at this constructor.
- FunctionProtoType::ExtProtoInfo EPI;
- EPI.ExceptionSpecType = EST_Unevaluated;
- EPI.ExceptionSpecDecl = DefaultCon;
+ FunctionProtoType::ExtProtoInfo EPI = getImplicitMethodEPI(*this, DefaultCon);
DefaultCon->setType(Context.getFunctionType(Context.VoidTy, None, EPI));
// We don't need to use SpecialMemberIsTrivial here; triviality for default
@@ -8355,9 +8370,7 @@
Destructor->setImplicit();
// Build an exception specification pointing back at this destructor.
- FunctionProtoType::ExtProtoInfo EPI;
- EPI.ExceptionSpecType = EST_Unevaluated;
- EPI.ExceptionSpecDecl = Destructor;
+ FunctionProtoType::ExtProtoInfo EPI = getImplicitMethodEPI(*this, Destructor);
Destructor->setType(Context.getFunctionType(Context.VoidTy, None, EPI));
AddOverriddenMethods(ClassDecl, Destructor);
@@ -8861,9 +8874,8 @@
CopyAssignment->setImplicit();
// Build an exception specification pointing back at this member.
- FunctionProtoType::ExtProtoInfo EPI;
- EPI.ExceptionSpecType = EST_Unevaluated;
- EPI.ExceptionSpecDecl = CopyAssignment;
+ FunctionProtoType::ExtProtoInfo EPI =
+ getImplicitMethodEPI(*this, CopyAssignment);
CopyAssignment->setType(Context.getFunctionType(RetType, ArgType, EPI));
// Add the parameter to the operator.
@@ -9375,9 +9387,8 @@
MoveAssignment->setImplicit();
// Build an exception specification pointing back at this member.
- FunctionProtoType::ExtProtoInfo EPI;
- EPI.ExceptionSpecType = EST_Unevaluated;
- EPI.ExceptionSpecDecl = MoveAssignment;
+ FunctionProtoType::ExtProtoInfo EPI =
+ getImplicitMethodEPI(*this, MoveAssignment);
MoveAssignment->setType(Context.getFunctionType(RetType, ArgType, EPI));
// Add the parameter to the operator.
@@ -9732,9 +9743,8 @@
CopyConstructor->setDefaulted();
// Build an exception specification pointing back at this member.
- FunctionProtoType::ExtProtoInfo EPI;
- EPI.ExceptionSpecType = EST_Unevaluated;
- EPI.ExceptionSpecDecl = CopyConstructor;
+ FunctionProtoType::ExtProtoInfo EPI =
+ getImplicitMethodEPI(*this, CopyConstructor);
CopyConstructor->setType(
Context.getFunctionType(Context.VoidTy, ArgType, EPI));
@@ -9922,9 +9932,8 @@
MoveConstructor->setDefaulted();
// Build an exception specification pointing back at this member.
- FunctionProtoType::ExtProtoInfo EPI;
- EPI.ExceptionSpecType = EST_Unevaluated;
- EPI.ExceptionSpecDecl = MoveConstructor;
+ FunctionProtoType::ExtProtoInfo EPI =
+ getImplicitMethodEPI(*this, MoveConstructor);
MoveConstructor->setType(
Context.getFunctionType(Context.VoidTy, ArgType, EPI));
@@ -11646,27 +11655,11 @@
if (NewCC == OldCC)
return false;
- // If either of the calling conventions are set to "default", we need to pick
- // something more sensible based on the target. This supports code where the
- // one method explicitly sets thiscall, and another has no explicit calling
- // convention.
- CallingConv Default =
- Context.getTargetInfo().getDefaultCallingConv(TargetInfo::CCMT_Member);
- if (NewCC == CC_Default)
- NewCC = Default;
- if (OldCC == CC_Default)
- OldCC = Default;
-
- // If the calling conventions still don't match, then report the error
- if (NewCC != OldCC) {
- Diag(New->getLocation(),
- diag::err_conflicting_overriding_cc_attributes)
- << New->getDeclName() << New->getType() << Old->getType();
- Diag(Old->getLocation(), diag::note_overridden_virtual_function);
- return true;
- }
-
- return false;
+ Diag(New->getLocation(),
+ diag::err_conflicting_overriding_cc_attributes)
+ << New->getDeclName() << New->getType() << Old->getType();
+ Diag(Old->getLocation(), diag::note_overridden_virtual_function);
+ return true;
}
bool Sema::CheckOverridingFunctionReturnType(const CXXMethodDecl *New,
diff --git a/lib/Sema/SemaLambda.cpp b/lib/Sema/SemaLambda.cpp
index ae3a938..242105f 100644
--- a/lib/Sema/SemaLambda.cpp
+++ b/lib/Sema/SemaLambda.cpp
@@ -539,7 +539,8 @@
// C++11 [expr.prim.lambda]p4:
// If a lambda-expression does not include a lambda-declarator, it is as
// if the lambda-declarator were ().
- FunctionProtoType::ExtProtoInfo EPI;
+ FunctionProtoType::ExtProtoInfo EPI(Context.getDefaultCallingConvention(
+ /*IsVariadic=*/false, /*IsCXXMethod=*/true));
EPI.HasTrailingReturn = true;
EPI.TypeQuals |= DeclSpec::TQ_const;
QualType MethodTy = Context.getFunctionType(Context.DependentTy, None,
@@ -819,17 +820,20 @@
QualType FunctionTy;
{
FunctionProtoType::ExtProtoInfo ExtInfo = Proto->getExtProtoInfo();
+ CallingConv CC = S.Context.getDefaultCallingConvention(
+ Proto->isVariadic(), /*IsCXXMethod=*/false);
+ ExtInfo.ExtInfo = ExtInfo.ExtInfo.withCallingConv(CC);
ExtInfo.TypeQuals = 0;
FunctionTy = S.Context.getFunctionType(Proto->getResultType(),
Proto->getArgTypes(), ExtInfo);
FunctionPtrTy = S.Context.getPointerType(FunctionTy);
}
-
- FunctionProtoType::ExtProtoInfo ExtInfo;
+
+ FunctionProtoType::ExtProtoInfo ExtInfo(S.Context.getDefaultCallingConvention(
+ /*IsVariadic=*/false, /*IsCXXMethod=*/true));
ExtInfo.TypeQuals = Qualifiers::Const;
- QualType ConvTy =
- S.Context.getFunctionType(FunctionPtrTy, None, ExtInfo);
-
+ QualType ConvTy = S.Context.getFunctionType(FunctionPtrTy, None, ExtInfo);
+
SourceLocation Loc = IntroducerRange.getBegin();
DeclarationName Name
= S.Context.DeclarationNames.getCXXConversionFunctionName(
@@ -893,8 +897,9 @@
Proto->getResultType(), Proto->getArgTypes(), ExtInfo);
BlockPtrTy = S.Context.getBlockPointerType(FunctionTy);
}
-
- FunctionProtoType::ExtProtoInfo ExtInfo;
+
+ FunctionProtoType::ExtProtoInfo ExtInfo(S.Context.getDefaultCallingConvention(
+ /*IsVariadic=*/false, /*IsCXXMethod=*/true));
ExtInfo.TypeQuals = Qualifiers::Const;
QualType ConvTy = S.Context.getFunctionType(BlockPtrTy, None, ExtInfo);
diff --git a/lib/Sema/SemaLookup.cpp b/lib/Sema/SemaLookup.cpp
index a17a903..c00ae69 100644
--- a/lib/Sema/SemaLookup.cpp
+++ b/lib/Sema/SemaLookup.cpp
@@ -728,7 +728,7 @@
// function to have, if it were to match the name given.
// FIXME: Calling convention!
FunctionProtoType::ExtProtoInfo EPI = ConvProto->getExtProtoInfo();
- EPI.ExtInfo = EPI.ExtInfo.withCallingConv(CC_Default);
+ EPI.ExtInfo = EPI.ExtInfo.withCallingConv(CC_C);
EPI.ExceptionSpecType = EST_None;
EPI.NumExceptions = 0;
QualType ExpectedType
diff --git a/lib/Sema/SemaType.cpp b/lib/Sema/SemaType.cpp
index 9664937..52b099e 100644
--- a/lib/Sema/SemaType.cpp
+++ b/lib/Sema/SemaType.cpp
@@ -1784,6 +1784,8 @@
}
}
+ // FIXME: Adjust member function pointer calling conventions.
+
return Context.getMemberPointerType(T, Class.getTypePtr());
}
@@ -2420,6 +2422,53 @@
}
}
+/// Helper for figuring out the default CC for a function declarator type. If
+/// this is the outermost chunk, then we can determine the CC from the
+/// declarator context. If not, then this could be either a member function
+/// type or normal function type.
+static CallingConv
+getCCForDeclaratorChunk(Sema &S, Declarator &D,
+ const DeclaratorChunk::FunctionTypeInfo &FTI,
+ unsigned ChunkIndex) {
+ assert(D.getTypeObject(ChunkIndex).Kind == DeclaratorChunk::Function);
+
+ bool IsCXXInstanceMethod = false;
+
+ if (S.getLangOpts().CPlusPlus) {
+ // Look inwards through parentheses to see if this chunk will form a
+ // member pointer type or if we're the declarator. Any type attributes
+ // between here and there will override the CC we choose here.
+ unsigned I = ChunkIndex;
+ bool FoundNonParen = false;
+ while (I && !FoundNonParen) {
+ --I;
+ if (D.getTypeObject(I).Kind != DeclaratorChunk::Paren)
+ FoundNonParen = true;
+ }
+
+ if (FoundNonParen) {
+ // If we're not the declarator, we're a regular function type unless we're
+ // in a member pointer.
+ IsCXXInstanceMethod =
+ D.getTypeObject(I).Kind == DeclaratorChunk::MemberPointer;
+ } else {
+ // We're the innermost decl chunk, so must be a function declarator.
+ assert(D.isFunctionDeclarator());
+
+ // If we're inside a record, we're declaring a method, but it could be
+ // static.
+ IsCXXInstanceMethod =
+ (D.getContext() == Declarator::MemberContext &&
+ D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef &&
+ D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static &&
+ !D.getDeclSpec().isFriendSpecified());
+ }
+ }
+
+ return S.Context.getDefaultCallingConvention(FTI.isVariadic,
+ IsCXXInstanceMethod);
+}
+
static TypeSourceInfo *GetFullTypeForDeclarator(TypeProcessingState &state,
QualType declSpecType,
TypeSourceInfo *TInfo) {
@@ -2793,9 +2842,11 @@
if (FTI.isAmbiguous)
warnAboutAmbiguousFunction(S, D, DeclType, T);
+ FunctionType::ExtInfo EI(getCCForDeclaratorChunk(S, D, FTI, chunkIndex));
+
if (!FTI.NumArgs && !FTI.isVariadic && !LangOpts.CPlusPlus) {
// Simple void foo(), where the incoming T is the result type.
- T = Context.getFunctionNoProtoType(T);
+ T = Context.getFunctionNoProtoType(T, EI);
} else {
// We allow a zero-parameter variadic function in C if the
// function is marked with the "overloadable" attribute. Scan
@@ -2820,11 +2871,12 @@
S.Diag(FTI.ArgInfo[0].IdentLoc, diag::err_ident_list_in_fn_declaration);
D.setInvalidType(true);
// Recover by creating a K&R-style function type.
- T = Context.getFunctionNoProtoType(T);
+ T = Context.getFunctionNoProtoType(T, EI);
break;
}
FunctionProtoType::ExtProtoInfo EPI;
+ EPI.ExtInfo = EI;
EPI.Variadic = FTI.isVariadic;
EPI.HasTrailingReturn = FTI.hasTrailingReturnType();
EPI.TypeQuals = FTI.TypeQuals;
@@ -4414,20 +4466,19 @@
const FunctionType *fn = unwrapped.get();
CallingConv CCOld = fn->getCallConv();
- if (S.Context.getCanonicalCallConv(CC) ==
- S.Context.getCanonicalCallConv(CCOld)) {
- FunctionType::ExtInfo EI= unwrapped.get()->getExtInfo().withCallingConv(CC);
- type = unwrapped.wrap(S, S.Context.adjustFunctionType(unwrapped.get(), EI));
- return true;
- }
+ AttributedType::Kind CCAttrKind = getCCTypeAttrKind(attr);
- if (CCOld != (S.LangOpts.MRTD ? CC_X86StdCall : CC_Default)) {
- // Should we diagnose reapplications of the same convention?
- S.Diag(attr.getLoc(), diag::err_attributes_are_not_compatible)
- << FunctionType::getNameForCallConv(CC)
- << FunctionType::getNameForCallConv(CCOld);
- attr.setInvalid();
- return true;
+ if (CC != CCOld) {
+ // Error out on when there's already an attribute on the type
+ // and the CCs don't match.
+ const AttributedType *AT = S.getCallingConvAttributedType(type);
+ if (AT && AT->getAttrKind() != CCAttrKind) {
+ S.Diag(attr.getLoc(), diag::err_attributes_are_not_compatible)
+ << FunctionType::getNameForCallConv(CC)
+ << FunctionType::getNameForCallConv(CCOld);
+ attr.setInvalid();
+ return true;
+ }
}
// Diagnose the use of X86 fastcall on varargs or unprototyped functions.
@@ -4463,10 +4514,38 @@
FunctionType::ExtInfo EI = unwrapped.get()->getExtInfo().withCallingConv(CC);
QualType Equivalent =
unwrapped.wrap(S, S.Context.adjustFunctionType(unwrapped.get(), EI));
- type = S.Context.getAttributedType(getCCTypeAttrKind(attr), type, Equivalent);
+ type = S.Context.getAttributedType(CCAttrKind, type, Equivalent);
return true;
}
+void Sema::adjustMemberFunctionCC(QualType &T) {
+ const FunctionType *FT = T->castAs<FunctionType>();
+ bool IsVariadic = (isa<FunctionProtoType>(FT) &&
+ cast<FunctionProtoType>(FT)->isVariadic());
+ CallingConv CC = FT->getCallConv();
+ CallingConv DefaultCC =
+ Context.getDefaultCallingConvention(IsVariadic, /*IsCXXMethod=*/false);
+ if (CC != DefaultCC)
+ return;
+
+ // Check if there was an explicit attribute, but only look through parens.
+ // The intent is to look for an attribute on the current declarator, but not
+ // one that came from a typedef.
+ QualType R = T.IgnoreParens();
+ while (const AttributedType *AT = dyn_cast<AttributedType>(R)) {
+ if (AT->isCallingConv())
+ return;
+ R = AT->getModifiedType().IgnoreParens();
+ }
+
+ // FIXME: This loses sugar. This should probably be fixed with an implicit
+ // AttributedType node that adjusts the convention.
+ CC = Context.getDefaultCallingConvention(IsVariadic, /*IsCXXMethod=*/true);
+ FT = Context.adjustFunctionType(FT, FT->getExtInfo().withCallingConv(CC));
+ FunctionTypeUnwrapper Unwrapped(*this, T);
+ T = Unwrapped.wrap(*this, FT);
+}
+
/// Handle OpenCL image access qualifiers: read_only, write_only, read_write
static void HandleOpenCLImageAccessAttribute(QualType& CurType,
const AttributeList &Attr,