//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// // // 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 declarations. // //===----------------------------------------------------------------------===// #include "Sema.h" #include "clang/AST/ASTConsumer.h" #include "clang/AST/ASTContext.h" #include "clang/AST/Attr.h" #include "clang/AST/Builtins.h" #include "clang/AST/Decl.h" #include "clang/AST/Expr.h" #include "clang/AST/Type.h" #include "clang/Parse/DeclSpec.h" #include "clang/Parse/Scope.h" #include "clang/Basic/LangOptions.h" #include "clang/Basic/TargetInfo.h" #include "clang/Basic/SourceManager.h" #include "clang/AST/ExprCXX.h" // FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) #include "clang/Lex/Preprocessor.h" #include "clang/Lex/HeaderSearch.h" #include "llvm/ADT/SmallString.h" #include "llvm/ADT/SmallSet.h" #include "llvm/ADT/DenseSet.h" using namespace clang; Sema::DeclTy *Sema::isTypeName(const IdentifierInfo &II, Scope *S) { Decl *IIDecl = LookupDecl(&II, Decl::IDNS_Ordinary, S, false); if (IIDecl && (isa(IIDecl) || isa(IIDecl) || isa(IIDecl))) return IIDecl; return 0; } void Sema::PushDeclContext(DeclContext *DC) { assert( ( (isa(DC) && isa(CurContext)) || DC->getParent() == CurContext ) && "The next DeclContext should be directly contained in the current one."); CurContext = DC; } void Sema::PopDeclContext() { assert(CurContext && "DeclContext imbalance!"); // If CurContext is a ObjC method, getParent() will return NULL. CurContext = isa(CurContext) ? Context.getTranslationUnitDecl() : CurContext->getParent(); } /// Add this decl to the scope shadowed decl chains. void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { S->AddDecl(D); // C++ [basic.scope]p4: // -- exactly one declaration shall declare a class name or // enumeration name that is not a typedef name and the other // declarations shall all refer to the same object or // enumerator, or all refer to functions and function templates; // in this case the class name or enumeration name is hidden. if (TagDecl *TD = dyn_cast(D)) { // We are pushing the name of a tag (enum or class). IdentifierResolver::ctx_iterator CIT = IdResolver.ctx_begin(TD->getIdentifier(), TD->getDeclContext()); if (CIT != IdResolver.ctx_end(TD->getIdentifier()) && IdResolver.isDeclInScope(*CIT, TD->getDeclContext(), S)) { // There is already a declaration with the same name in the same // scope. It must be found before we find the new declaration, // so swap the order on the shadowed declaration chain. IdResolver.AddShadowedDecl(TD, *CIT); return; } } IdResolver.AddDecl(D); } void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { if (S->decl_empty()) return; assert((S->getFlags() & Scope::DeclScope) &&"Scope shouldn't contain decls!"); // We only want to remove the decls from the identifier decl chains for local // scopes, when inside a function/method. if (S->getFnParent() == 0) return; for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); I != E; ++I) { Decl *TmpD = static_cast(*I); assert(TmpD && "This decl didn't get pushed??"); ScopedDecl *D = dyn_cast(TmpD); assert(D && "This decl isn't a ScopedDecl?"); IdentifierInfo *II = D->getIdentifier(); if (!II) continue; // Unlink this decl from the identifier. IdResolver.RemoveDecl(D); // This will have to be revisited for C++: there we want to nest stuff in // namespace decls etc. Even for C, we might want a top-level translation // unit decl or something. if (!CurFunctionDecl) continue; // Chain this decl to the containing function, it now owns the memory for // the decl. D->setNext(CurFunctionDecl->getDeclChain()); CurFunctionDecl->setDeclChain(D); } } /// getObjCInterfaceDecl - Look up a for a class declaration in the scope. /// return 0 if one not found. ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { // The third "scope" argument is 0 since we aren't enabling lazy built-in // creation from this context. Decl *IDecl = LookupDecl(Id, Decl::IDNS_Ordinary, 0, false); return dyn_cast_or_null(IDecl); } /// LookupDecl - Look up the inner-most declaration in the specified /// namespace. Decl *Sema::LookupDecl(const IdentifierInfo *II, unsigned NSI, Scope *S, bool enableLazyBuiltinCreation) { if (II == 0) return 0; unsigned NS = NSI; if (getLangOptions().CPlusPlus && (NS & Decl::IDNS_Ordinary)) NS |= Decl::IDNS_Tag; // Scan up the scope chain looking for a decl that matches this identifier // that is in the appropriate namespace. This search should not take long, as // shadowing of names is uncommon, and deep shadowing is extremely uncommon. for (IdentifierResolver::iterator I = IdResolver.begin(II, CurContext), E = IdResolver.end(II); I != E; ++I) if ((*I)->getIdentifierNamespace() & NS) return *I; // If we didn't find a use of this identifier, and if the identifier // corresponds to a compiler builtin, create the decl object for the builtin // now, injecting it into translation unit scope, and return it. if (NS & Decl::IDNS_Ordinary) { if (enableLazyBuiltinCreation) { // If this is a builtin on this (or all) targets, create the decl. if (unsigned BuiltinID = II->getBuiltinID()) return LazilyCreateBuiltin((IdentifierInfo *)II, BuiltinID, S); } if (getLangOptions().ObjC1) { // @interface and @compatibility_alias introduce typedef-like names. // Unlike typedef's, they can only be introduced at file-scope (and are // therefore not scoped decls). They can, however, be shadowed by // other names in IDNS_Ordinary. ObjCInterfaceDeclsTy::iterator IDI = ObjCInterfaceDecls.find(II); if (IDI != ObjCInterfaceDecls.end()) return IDI->second; ObjCAliasTy::iterator I = ObjCAliasDecls.find(II); if (I != ObjCAliasDecls.end()) return I->second->getClassInterface(); } } return 0; } void Sema::InitBuiltinVaListType() { if (!Context.getBuiltinVaListType().isNull()) return; IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); Decl *VaDecl = LookupDecl(VaIdent, Decl::IDNS_Ordinary, TUScope); TypedefDecl *VaTypedef = cast(VaDecl); Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); } /// LazilyCreateBuiltin - The specified Builtin-ID was first used at file scope. /// lazily create a decl for it. ScopedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, Scope *S) { Builtin::ID BID = (Builtin::ID)bid; if (BID == Builtin::BI__builtin_va_start || BID == Builtin::BI__builtin_va_copy || BID == Builtin::BI__builtin_va_end) InitBuiltinVaListType(); QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context); FunctionDecl *New = FunctionDecl::Create(Context, Context.getTranslationUnitDecl(), SourceLocation(), II, R, FunctionDecl::Extern, false, 0); // Create Decl objects for each parameter, adding them to the // FunctionDecl. if (FunctionTypeProto *FT = dyn_cast(R)) { llvm::SmallVector Params; for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, FT->getArgType(i), VarDecl::None, 0, 0)); New->setParams(&Params[0], Params.size()); } // TUScope is the translation-unit scope to insert this function into. PushOnScopeChains(New, TUScope); return New; } /// MergeTypeDefDecl - We just parsed a typedef 'New' which has the same name /// and scope as a previous declaration 'Old'. Figure out how to resolve this /// situation, merging decls or emitting diagnostics as appropriate. /// TypedefDecl *Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { // Verify the old decl was also a typedef. TypedefDecl *Old = dyn_cast(OldD); if (!Old) { Diag(New->getLocation(), diag::err_redefinition_different_kind, New->getName()); Diag(OldD->getLocation(), diag::err_previous_definition); return New; } // Allow multiple definitions for ObjC built-in typedefs. // FIXME: Verify the underlying types are equivalent! if (getLangOptions().ObjC1 && isBuiltinObjCType(New)) return Old; // Redeclaration of a type is a constraint violation (6.7.2.3p1). // Apparently GCC, Intel, and Sun all silently ignore the redeclaration if // *either* declaration is in a system header. The code below implements // this adhoc compatibility rule. FIXME: The following code will not // work properly when compiling ".i" files (containing preprocessed output). SourceManager &SrcMgr = Context.getSourceManager(); const FileEntry *OldDeclFile = SrcMgr.getFileEntryForLoc(Old->getLocation()); const FileEntry *NewDeclFile = SrcMgr.getFileEntryForLoc(New->getLocation()); HeaderSearch &HdrInfo = PP.getHeaderSearchInfo(); DirectoryLookup::DirType OldDirType = HdrInfo.getFileDirFlavor(OldDeclFile); DirectoryLookup::DirType NewDirType = HdrInfo.getFileDirFlavor(NewDeclFile); // Allow reclarations in both SystemHeaderDir and ExternCSystemHeaderDir. if ((OldDirType != DirectoryLookup::NormalHeaderDir || NewDirType != DirectoryLookup::NormalHeaderDir) || getLangOptions().Microsoft) return New; // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. // TODO: This is totally simplistic. It should handle merging functions // together etc, merging extern int X; int X; ... Diag(New->getLocation(), diag::err_redefinition, New->getName()); Diag(Old->getLocation(), diag::err_previous_definition); return New; } /// DeclhasAttr - returns true if decl Declaration already has the target attribute. static bool DeclHasAttr(const Decl *decl, const Attr *target) { for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) if (attr->getKind() == target->getKind()) return true; return false; } /// MergeAttributes - append attributes from the Old decl to the New one. static void MergeAttributes(Decl *New, Decl *Old) { Attr *attr = const_cast(Old->getAttrs()), *tmp; while (attr) { tmp = attr; attr = attr->getNext(); if (!DeclHasAttr(New, tmp)) { New->addAttr(tmp); } else { tmp->setNext(0); delete(tmp); } } Old->invalidateAttrs(); } /// MergeFunctionDecl - We just parsed a function 'New' from /// declarator D which has the same name and scope as a previous /// declaration 'Old'. Figure out how to resolve this situation, /// merging decls or emitting diagnostics as appropriate. /// Redeclaration will be set true if thisNew is a redeclaration OldD. FunctionDecl * Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD, bool &Redeclaration) { Redeclaration = false; // Verify the old decl was also a function. FunctionDecl *Old = dyn_cast(OldD); if (!Old) { Diag(New->getLocation(), diag::err_redefinition_different_kind, New->getName()); Diag(OldD->getLocation(), diag::err_previous_definition); return New; } QualType OldQType = Context.getCanonicalType(Old->getType()); QualType NewQType = Context.getCanonicalType(New->getType()); // C++ [dcl.fct]p3: // All declarations for a function shall agree exactly in both the // return type and the parameter-type-list. if (getLangOptions().CPlusPlus && OldQType == NewQType) { MergeAttributes(New, Old); Redeclaration = true; return MergeCXXFunctionDecl(New, Old); } // C: Function types need to be compatible, not identical. This handles // duplicate function decls like "void f(int); void f(enum X);" properly. if (!getLangOptions().CPlusPlus && Context.functionTypesAreCompatible(OldQType, NewQType)) { MergeAttributes(New, Old); Redeclaration = true; return New; } // A function that has already been declared has been redeclared or defined // with a different type- show appropriate diagnostic diag::kind PrevDiag; if (Old->isThisDeclarationADefinition()) PrevDiag = diag::err_previous_definition; else if (Old->isImplicit()) PrevDiag = diag::err_previous_implicit_declaration; else PrevDiag = diag::err_previous_declaration; // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. // TODO: This is totally simplistic. It should handle merging functions // together etc, merging extern int X; int X; ... Diag(New->getLocation(), diag::err_conflicting_types, New->getName()); Diag(Old->getLocation(), PrevDiag); return New; } /// equivalentArrayTypes - Used to determine whether two array types are /// equivalent. /// We need to check this explicitly as an incomplete array definition is /// considered a VariableArrayType, so will not match a complete array /// definition that would be otherwise equivalent. static bool areEquivalentArrayTypes(QualType NewQType, QualType OldQType) { const ArrayType *NewAT = NewQType->getAsArrayType(); const ArrayType *OldAT = OldQType->getAsArrayType(); if (!NewAT || !OldAT) return false; // If either (or both) array types in incomplete we need to strip off the // outer VariableArrayType. Once the outer VAT is removed the remaining // types must be identical if the array types are to be considered // equivalent. // eg. int[][1] and int[1][1] become // VAT(null, CAT(1, int)) and CAT(1, CAT(1, int)) // removing the outermost VAT gives // CAT(1, int) and CAT(1, int) // which are equal, therefore the array types are equivalent. if (NewAT->isIncompleteArrayType() || OldAT->isIncompleteArrayType()) { if (NewAT->getIndexTypeQualifier() != OldAT->getIndexTypeQualifier()) return false; NewQType = NewAT->getElementType().getCanonicalType(); OldQType = OldAT->getElementType().getCanonicalType(); } return NewQType == OldQType; } /// MergeVarDecl - We just parsed a variable 'New' which has the same name /// and scope as a previous declaration 'Old'. Figure out how to resolve this /// situation, merging decls or emitting diagnostics as appropriate. /// /// FIXME: Need to carefully consider tentative definition rules (C99 6.9.2p2). /// For example, we incorrectly complain about i1, i4 from C99 6.9.2p4. /// VarDecl *Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { // Verify the old decl was also a variable. VarDecl *Old = dyn_cast(OldD); if (!Old) { Diag(New->getLocation(), diag::err_redefinition_different_kind, New->getName()); Diag(OldD->getLocation(), diag::err_previous_definition); return New; } MergeAttributes(New, Old); // Verify the types match. QualType OldCType = Context.getCanonicalType(Old->getType()); QualType NewCType = Context.getCanonicalType(New->getType()); if (OldCType != NewCType && !areEquivalentArrayTypes(NewCType, OldCType)) { Diag(New->getLocation(), diag::err_redefinition, New->getName()); Diag(Old->getLocation(), diag::err_previous_definition); return New; } // C99 6.2.2p4: Check if we have a static decl followed by a non-static. if (New->getStorageClass() == VarDecl::Static && (Old->getStorageClass() == VarDecl::None || Old->getStorageClass() == VarDecl::Extern)) { Diag(New->getLocation(), diag::err_static_non_static, New->getName()); Diag(Old->getLocation(), diag::err_previous_definition); return New; } // C99 6.2.2p4: Check if we have a non-static decl followed by a static. if (New->getStorageClass() != VarDecl::Static && Old->getStorageClass() == VarDecl::Static) { Diag(New->getLocation(), diag::err_non_static_static, New->getName()); Diag(Old->getLocation(), diag::err_previous_definition); return New; } // We've verified the types match, now handle "tentative" definitions. if (Old->isFileVarDecl() && New->isFileVarDecl()) { // Handle C "tentative" external object definitions (C99 6.9.2). bool OldIsTentative = false; bool NewIsTentative = false; if (!Old->getInit() && (Old->getStorageClass() == VarDecl::None || Old->getStorageClass() == VarDecl::Static)) OldIsTentative = true; // FIXME: this check doesn't work (since the initializer hasn't been // attached yet). This check should be moved to FinalizeDeclaratorGroup. // Unfortunately, by the time we get to FinializeDeclaratorGroup, we've // thrown out the old decl. if (!New->getInit() && (New->getStorageClass() == VarDecl::None || New->getStorageClass() == VarDecl::Static)) ; // change to NewIsTentative = true; once the code is moved. if (NewIsTentative || OldIsTentative) return New; } // Handle __private_extern__ just like extern. if (Old->getStorageClass() != VarDecl::Extern && Old->getStorageClass() != VarDecl::PrivateExtern && New->getStorageClass() != VarDecl::Extern && New->getStorageClass() != VarDecl::PrivateExtern) { Diag(New->getLocation(), diag::err_redefinition, New->getName()); Diag(Old->getLocation(), diag::err_previous_definition); } return New; } /// CheckParmsForFunctionDef - Check that the parameters of the given /// function are appropriate for the definition of a function. This /// takes care of any checks that cannot be performed on the /// declaration itself, e.g., that the types of each of the function /// parameters are complete. bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { bool HasInvalidParm = false; for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { ParmVarDecl *Param = FD->getParamDecl(p); // C99 6.7.5.3p4: the parameters in a parameter type list in a // function declarator that is part of a function definition of // that function shall not have incomplete type. if (Param->getType()->isIncompleteType() && !Param->isInvalidDecl()) { Diag(Param->getLocation(), diag::err_typecheck_decl_incomplete_type, Param->getType().getAsString()); Param->setInvalidDecl(); HasInvalidParm = true; } } return HasInvalidParm; } /// CreateImplicitParameter - Creates an implicit function parameter /// in the scope S and with the given type. This routine is used, for /// example, to create the implicit "self" parameter in an Objective-C /// method. ParmVarDecl * Sema::CreateImplicitParameter(Scope *S, IdentifierInfo *Id, SourceLocation IdLoc, QualType Type) { ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, IdLoc, Id, Type, VarDecl::None, 0, 0); if (Id) PushOnScopeChains(New, S); return New; } /// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with /// no declarator (e.g. "struct foo;") is parsed. Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { // TODO: emit error on 'int;' or 'const enum foo;'. // TODO: emit error on 'typedef int;' // if (!DS.isMissingDeclaratorOk()) Diag(...); return dyn_cast_or_null(static_cast(DS.getTypeRep())); } bool Sema::CheckSingleInitializer(Expr *&Init, QualType DeclType) { // Get the type before calling CheckSingleAssignmentConstraints(), since // it can promote the expression. QualType InitType = Init->getType(); AssignConvertType ConvTy = CheckSingleAssignmentConstraints(DeclType, Init); return DiagnoseAssignmentResult(ConvTy, Init->getLocStart(), DeclType, InitType, Init, "initializing"); } bool Sema::CheckInitExpr(Expr *expr, InitListExpr *IList, unsigned slot, QualType ElementType) { Expr *savExpr = expr; // Might be promoted by CheckSingleInitializer. if (CheckSingleInitializer(expr, ElementType)) return true; // types weren't compatible. if (savExpr != expr) // The type was promoted, update initializer list. IList->setInit(slot, expr); return false; } bool Sema::CheckStringLiteralInit(StringLiteral *strLiteral, QualType &DeclT) { if (const IncompleteArrayType *IAT = DeclT->getAsIncompleteArrayType()) { // C99 6.7.8p14. We have an array of character type with unknown size // being initialized to a string literal. llvm::APSInt ConstVal(32); ConstVal = strLiteral->getByteLength() + 1; // Return a new array type (C99 6.7.8p22). DeclT = Context.getConstantArrayType(IAT->getElementType(), ConstVal, ArrayType::Normal, 0); } else if (const ConstantArrayType *CAT = DeclT->getAsConstantArrayType()) { // C99 6.7.8p14. We have an array of character type with known size. if (strLiteral->getByteLength() > (unsigned)CAT->getMaximumElements()) Diag(strLiteral->getSourceRange().getBegin(), diag::warn_initializer_string_for_char_array_too_long, strLiteral->getSourceRange()); } else { assert(0 && "HandleStringLiteralInit(): Invalid array type"); } // Set type from "char *" to "constant array of char". strLiteral->setType(DeclT); // For now, we always return false (meaning success). return false; } StringLiteral *Sema::IsStringLiteralInit(Expr *Init, QualType DeclType) { const ArrayType *AT = DeclType->getAsArrayType(); if (AT && AT->getElementType()->isCharType()) { return dyn_cast(Init); } return 0; } // CheckInitializerListTypes - Checks the types of elements of an initializer // list. This function is recursive: it calls itself to initialize subelements // of aggregate types. Note that the topLevel parameter essentially refers to // whether this expression "owns" the initializer list passed in, or if this // initialization is taking elements out of a parent initializer. Each // call to this function adds zero or more to startIndex, reports any errors, // and returns true if it found any inconsistent types. bool Sema::CheckInitializerListTypes(InitListExpr*& IList, QualType &DeclType, bool topLevel, unsigned& startIndex) { bool hadError = false; if (DeclType->isScalarType()) { // The simplest case: initializing a single scalar if (topLevel) { Diag(IList->getLocStart(), diag::warn_braces_around_scalar_init, IList->getSourceRange()); } if (startIndex < IList->getNumInits()) { Expr* expr = IList->getInit(startIndex); if (InitListExpr *SubInitList = dyn_cast(expr)) { // FIXME: Should an error be reported here instead? unsigned newIndex = 0; CheckInitializerListTypes(SubInitList, DeclType, true, newIndex); } else { hadError |= CheckInitExpr(expr, IList, startIndex, DeclType); } ++startIndex; } // FIXME: Should an error be reported for empty initializer list + scalar? } else if (DeclType->isVectorType()) { if (startIndex < IList->getNumInits()) { const VectorType *VT = DeclType->getAsVectorType(); int maxElements = VT->getNumElements(); QualType elementType = VT->getElementType(); for (int i = 0; i < maxElements; ++i) { // Don't attempt to go past the end of the init list if (startIndex >= IList->getNumInits()) break; Expr* expr = IList->getInit(startIndex); if (InitListExpr *SubInitList = dyn_cast(expr)) { unsigned newIndex = 0; hadError |= CheckInitializerListTypes(SubInitList, elementType, true, newIndex); ++startIndex; } else { hadError |= CheckInitializerListTypes(IList, elementType, false, startIndex); } } } } else if (DeclType->isAggregateType() || DeclType->isUnionType()) { if (DeclType->isStructureType() || DeclType->isUnionType()) { if (startIndex < IList->getNumInits() && !topLevel && Context.typesAreCompatible(IList->getInit(startIndex)->getType(), DeclType)) { // We found a compatible struct; per the standard, this initializes the // struct. (The C standard technically says that this only applies for // initializers for declarations with automatic scope; however, this // construct is unambiguous anyway because a struct cannot contain // a type compatible with itself. We'll output an error when we check // if the initializer is constant.) // FIXME: Is a call to CheckSingleInitializer required here? ++startIndex; } else { RecordDecl* structDecl = DeclType->getAsRecordType()->getDecl(); // If the record is invalid, some of it's members are invalid. To avoid // confusion, we forgo checking the intializer for the entire record. if (structDecl->isInvalidDecl()) return true; // If structDecl is a forward declaration, this loop won't do anything; // That's okay, because an error should get printed out elsewhere. It // might be worthwhile to skip over the rest of the initializer, though. int numMembers = structDecl->getNumMembers() - structDecl->hasFlexibleArrayMember(); for (int i = 0; i < numMembers; i++) { // Don't attempt to go past the end of the init list if (startIndex >= IList->getNumInits()) break; FieldDecl * curField = structDecl->getMember(i); if (!curField->getIdentifier()) { // Don't initialize unnamed fields, e.g. "int : 20;" continue; } QualType fieldType = curField->getType(); Expr* expr = IList->getInit(startIndex); if (InitListExpr *SubInitList = dyn_cast(expr)) { unsigned newStart = 0; hadError |= CheckInitializerListTypes(SubInitList, fieldType, true, newStart); ++startIndex; } else { hadError |= CheckInitializerListTypes(IList, fieldType, false, startIndex); } if (DeclType->isUnionType()) break; } // FIXME: Implement flexible array initialization GCC extension (it's a // really messy extension to implement, unfortunately...the necessary // information isn't actually even here!) } } else if (DeclType->isArrayType()) { // Check for the special-case of initializing an array with a string. if (startIndex < IList->getNumInits()) { if (StringLiteral *lit = IsStringLiteralInit(IList->getInit(startIndex), DeclType)) { CheckStringLiteralInit(lit, DeclType); ++startIndex; if (topLevel && startIndex < IList->getNumInits()) { // We have leftover initializers; warn Diag(IList->getInit(startIndex)->getLocStart(), diag::err_excess_initializers_in_char_array_initializer, IList->getInit(startIndex)->getSourceRange()); } return false; } } int maxElements; if (DeclType->isIncompleteArrayType()) { // FIXME: use a proper constant maxElements = 0x7FFFFFFF; } else if (const VariableArrayType *VAT = DeclType->getAsVariableArrayType()) { // Check for VLAs; in standard C it would be possible to check this // earlier, but I don't know where clang accepts VLAs (gcc accepts // them in all sorts of strange places). Diag(VAT->getSizeExpr()->getLocStart(), diag::err_variable_object_no_init, VAT->getSizeExpr()->getSourceRange()); hadError = true; maxElements = 0x7FFFFFFF; } else { const ConstantArrayType *CAT = DeclType->getAsConstantArrayType(); maxElements = static_cast(CAT->getSize().getZExtValue()); } QualType elementType = DeclType->getAsArrayType()->getElementType(); int numElements = 0; for (int i = 0; i < maxElements; ++i, ++numElements) { // Don't attempt to go past the end of the init list if (startIndex >= IList->getNumInits()) break; Expr* expr = IList->getInit(startIndex); if (InitListExpr *SubInitList = dyn_cast(expr)) { unsigned newIndex = 0; hadError |= CheckInitializerListTypes(SubInitList, elementType, true, newIndex); ++startIndex; } else { hadError |= CheckInitializerListTypes(IList, elementType, false, startIndex); } } if (DeclType->isIncompleteArrayType()) { // If this is an incomplete array type, the actual type needs to // be calculated here if (numElements == 0) { // Sizing an array implicitly to zero is not allowed // (It could in theory be allowed, but it doesn't really matter.) Diag(IList->getLocStart(), diag::err_at_least_one_initializer_needed_to_size_array); hadError = true; } else { llvm::APSInt ConstVal(32); ConstVal = numElements; DeclType = Context.getConstantArrayType(elementType, ConstVal, ArrayType::Normal, 0); } } } else { assert(0 && "Aggregate that isn't a function or array?!"); } } else { // In C, all types are either scalars or aggregates, but // additional handling is needed here for C++ (and possibly others?). assert(0 && "Unsupported initializer type"); } // If this init list is a base list, we set the type; an initializer doesn't // fundamentally have a type, but this makes the ASTs a bit easier to read if (topLevel) IList->setType(DeclType); if (topLevel && startIndex < IList->getNumInits()) { // We have leftover initializers; warn Diag(IList->getInit(startIndex)->getLocStart(), diag::warn_excess_initializers, IList->getInit(startIndex)->getSourceRange()); } return hadError; } bool Sema::CheckInitializerTypes(Expr *&Init, QualType &DeclType) { // C99 6.7.8p3: The type of the entity to be initialized shall be an array // of unknown size ("[]") or an object type that is not a variable array type. if (const VariableArrayType *VAT = DeclType->getAsVariableArrayType()) return Diag(VAT->getSizeExpr()->getLocStart(), diag::err_variable_object_no_init, VAT->getSizeExpr()->getSourceRange()); InitListExpr *InitList = dyn_cast(Init); if (!InitList) { // FIXME: Handle wide strings if (StringLiteral *strLiteral = IsStringLiteralInit(Init, DeclType)) return CheckStringLiteralInit(strLiteral, DeclType); if (DeclType->isArrayType()) return Diag(Init->getLocStart(), diag::err_array_init_list_required, Init->getSourceRange()); return CheckSingleInitializer(Init, DeclType); } #if 0 unsigned newIndex = 0; return CheckInitializerListTypes(InitList, DeclType, true, newIndex); #else InitListChecker CheckInitList(this, InitList, DeclType); return CheckInitList.HadError(); #endif } Sema::DeclTy * Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl) { ScopedDecl *LastDeclarator = dyn_cast_or_null((Decl *)lastDecl); IdentifierInfo *II = D.getIdentifier(); // All of these full declarators require an identifier. If it doesn't have // one, the ParsedFreeStandingDeclSpec action should be used. if (II == 0) { Diag(D.getDeclSpec().getSourceRange().getBegin(), diag::err_declarator_need_ident, D.getDeclSpec().getSourceRange(), D.getSourceRange()); return 0; } // The scope passed in may not be a decl scope. Zip up the scope tree until // we find one that is. while ((S->getFlags() & Scope::DeclScope) == 0) S = S->getParent(); // See if this is a redefinition of a variable in the same scope. Decl *PrevDecl = LookupDecl(II, Decl::IDNS_Ordinary, S); ScopedDecl *New; bool InvalidDecl = false; // In C++, the previous declaration we find might be a tag type // (class or enum). In this case, the new declaration will hide the // tag type. if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag) PrevDecl = 0; QualType R = GetTypeForDeclarator(D, S); assert(!R.isNull() && "GetTypeForDeclarator() returned null type"); if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { // Check that there are no default arguments (C++ only). if (getLangOptions().CPlusPlus) CheckExtraCXXDefaultArguments(D); TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); if (!NewTD) return 0; // Handle attributes prior to checking for duplicates in MergeVarDecl HandleDeclAttributes(NewTD, D.getDeclSpec().getAttributes(), D.getAttributes()); // Merge the decl with the existing one if appropriate. If the decl is // in an outer scope, it isn't the same thing. if (PrevDecl && IdResolver.isDeclInScope(PrevDecl, CurContext, S)) { NewTD = MergeTypeDefDecl(NewTD, PrevDecl); if (NewTD == 0) return 0; } New = NewTD; if (S->getFnParent() == 0) { // C99 6.7.7p2: If a typedef name specifies a variably modified type // then it shall have block scope. if (NewTD->getUnderlyingType()->isVariablyModifiedType()) { // FIXME: Diagnostic needs to be fixed. Diag(D.getIdentifierLoc(), diag::err_typecheck_illegal_vla); InvalidDecl = true; } } } else if (R.getTypePtr()->isFunctionType()) { FunctionDecl::StorageClass SC = FunctionDecl::None; switch (D.getDeclSpec().getStorageClassSpec()) { default: assert(0 && "Unknown storage class!"); case DeclSpec::SCS_auto: case DeclSpec::SCS_register: Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_func, R.getAsString()); InvalidDecl = true; break; case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; case DeclSpec::SCS_static: SC = FunctionDecl::Static; break; case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; } bool isInline = D.getDeclSpec().isInlineSpecified(); FunctionDecl *NewFD = FunctionDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, R, SC, isInline, LastDeclarator); // Handle attributes. HandleDeclAttributes(NewFD, D.getDeclSpec().getAttributes(), D.getAttributes()); // Copy the parameter declarations from the declarator D to // the function declaration NewFD, if they are available. if (D.getNumTypeObjects() > 0 && D.getTypeObject(0).Fun.hasPrototype) { DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; // Create Decl objects for each parameter, adding them to the // FunctionDecl. llvm::SmallVector Params; // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs // function that takes no arguments, not a function that takes a // single void argument. // We let through "const void" here because Sema::GetTypeForDeclarator // already checks for that case. if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && FTI.ArgInfo[0].Param && ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { // empty arg list, don't push any params. ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; // In C++, the empty parameter-type-list must be spelled "void"; a // typedef of void is not permitted. if (getLangOptions().CPlusPlus && Param->getType().getUnqualifiedType() != Context.VoidTy) { Diag(Param->getLocation(), diag::ext_param_typedef_of_void); } } else { for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); } NewFD->setParams(&Params[0], Params.size()); } // Merge the decl with the existing one if appropriate. Since C functions // are in a flat namespace, make sure we consider decls in outer scopes. if (PrevDecl && (!getLangOptions().CPlusPlus || IdResolver.isDeclInScope(PrevDecl, CurContext, S)) ) { bool Redeclaration = false; NewFD = MergeFunctionDecl(NewFD, PrevDecl, Redeclaration); if (NewFD == 0) return 0; if (Redeclaration) { NewFD->setPreviousDeclaration(cast(PrevDecl)); } } New = NewFD; // In C++, check default arguments now that we have merged decls. if (getLangOptions().CPlusPlus) CheckCXXDefaultArguments(NewFD); } else { // Check that there are no default arguments (C++ only). if (getLangOptions().CPlusPlus) CheckExtraCXXDefaultArguments(D); if (R.getTypePtr()->isObjCInterfaceType()) { Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object, D.getIdentifier()->getName()); InvalidDecl = true; } VarDecl *NewVD; VarDecl::StorageClass SC; switch (D.getDeclSpec().getStorageClassSpec()) { default: assert(0 && "Unknown storage class!"); case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; case DeclSpec::SCS_static: SC = VarDecl::Static; break; case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; case DeclSpec::SCS_register: SC = VarDecl::Register; break; case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; } if (S->getFnParent() == 0) { // C99 6.9p2: The storage-class specifiers auto and register shall not // appear in the declaration specifiers in an external declaration. if (SC == VarDecl::Auto || SC == VarDecl::Register) { Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope, R.getAsString()); InvalidDecl = true; } NewVD = VarDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, R, SC, LastDeclarator); } else { NewVD = VarDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, R, SC, LastDeclarator); } // Handle attributes prior to checking for duplicates in MergeVarDecl HandleDeclAttributes(NewVD, D.getDeclSpec().getAttributes(), D.getAttributes()); // Emit an error if an address space was applied to decl with local storage. // This includes arrays of objects with address space qualifiers, but not // automatic variables that point to other address spaces. // ISO/IEC TR 18037 S5.1.2 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); InvalidDecl = true; } // Merge the decl with the existing one if appropriate. If the decl is // in an outer scope, it isn't the same thing. if (PrevDecl && IdResolver.isDeclInScope(PrevDecl, CurContext, S)) { NewVD = MergeVarDecl(NewVD, PrevDecl); if (NewVD == 0) return 0; } New = NewVD; } // If this has an identifier, add it to the scope stack. if (II) PushOnScopeChains(New, S); // If any semantic error occurred, mark the decl as invalid. if (D.getInvalidType() || InvalidDecl) New->setInvalidDecl(); return New; } bool Sema::CheckAddressConstantExpressionLValue(const Expr* Init) { switch (Init->getStmtClass()) { default: Diag(Init->getExprLoc(), diag::err_init_element_not_constant, Init->getSourceRange()); return true; case Expr::ParenExprClass: { const ParenExpr* PE = cast(Init); return CheckAddressConstantExpressionLValue(PE->getSubExpr()); } case Expr::CompoundLiteralExprClass: return cast(Init)->isFileScope(); case Expr::DeclRefExprClass: { const Decl *D = cast(Init)->getDecl(); if (const VarDecl *VD = dyn_cast(D)) { if (VD->hasGlobalStorage()) return false; Diag(Init->getExprLoc(), diag::err_init_element_not_constant, Init->getSourceRange()); return true; } if (isa(D)) return false; Diag(Init->getExprLoc(), diag::err_init_element_not_constant, Init->getSourceRange()); return true; } case Expr::MemberExprClass: { const MemberExpr *M = cast(Init); if (M->isArrow()) return CheckAddressConstantExpression(M->getBase()); return CheckAddressConstantExpressionLValue(M->getBase()); } case Expr::ArraySubscriptExprClass: { // FIXME: Should we pedwarn for "x[0+0]" (where x is a pointer)? const ArraySubscriptExpr *ASE = cast(Init); return CheckAddressConstantExpression(ASE->getBase()) || CheckArithmeticConstantExpression(ASE->getIdx()); } case Expr::StringLiteralClass: case Expr::PreDefinedExprClass: return false; case Expr::UnaryOperatorClass: { const UnaryOperator *Exp = cast(Init); // C99 6.6p9 if (Exp->getOpcode() == UnaryOperator::Deref) return CheckAddressConstantExpression(Exp->getSubExpr()); Diag(Init->getExprLoc(), diag::err_init_element_not_constant, Init->getSourceRange()); return true; } } } bool Sema::CheckAddressConstantExpression(const Expr* Init) { switch (Init->getStmtClass()) { default: Diag(Init->getExprLoc(), diag::err_init_element_not_constant, Init->getSourceRange()); return true; case Expr::ParenExprClass: { const ParenExpr* PE = cast(Init); return CheckAddressConstantExpression(PE->getSubExpr()); } case Expr::StringLiteralClass: case Expr::ObjCStringLiteralClass: return false; case Expr::CallExprClass: { const CallExpr *CE = cast(Init); if (CE->isBuiltinConstantExpr()) return false; Diag(Init->getExprLoc(), diag::err_init_element_not_constant, Init->getSourceRange()); return true; } case Expr::UnaryOperatorClass: { const UnaryOperator *Exp = cast(Init); // C99 6.6p9 if (Exp->getOpcode() == UnaryOperator::AddrOf) return CheckAddressConstantExpressionLValue(Exp->getSubExpr()); if (Exp->getOpcode() == UnaryOperator::Extension) return CheckAddressConstantExpression(Exp->getSubExpr()); Diag(Init->getExprLoc(), diag::err_init_element_not_constant, Init->getSourceRange()); return true; } case Expr::BinaryOperatorClass: { // FIXME: Should we pedwarn for expressions like "a + 1 + 2"? const BinaryOperator *Exp = cast(Init); Expr *PExp = Exp->getLHS(); Expr *IExp = Exp->getRHS(); if (IExp->getType()->isPointerType()) std::swap(PExp, IExp); // FIXME: Should we pedwarn if IExp isn't an integer constant expression? return CheckAddressConstantExpression(PExp) || CheckArithmeticConstantExpression(IExp); } case Expr::ImplicitCastExprClass: { const Expr* SubExpr = cast(Init)->getSubExpr(); // Check for implicit promotion if (SubExpr->getType()->isFunctionType() || SubExpr->getType()->isArrayType()) return CheckAddressConstantExpressionLValue(SubExpr); // Check for pointer->pointer cast if (SubExpr->getType()->isPointerType()) return CheckAddressConstantExpression(SubExpr); if (SubExpr->getType()->isArithmeticType()) return CheckArithmeticConstantExpression(SubExpr); Diag(Init->getExprLoc(), diag::err_init_element_not_constant, Init->getSourceRange()); return true; } case Expr::CastExprClass: { const Expr* SubExpr = cast(Init)->getSubExpr(); // Check for pointer->pointer cast if (SubExpr->getType()->isPointerType()) return CheckAddressConstantExpression(SubExpr); // FIXME: Should we pedwarn for (int*)(0+0)? if (SubExpr->getType()->isArithmeticType()) return CheckArithmeticConstantExpression(SubExpr); Diag(Init->getExprLoc(), diag::err_init_element_not_constant, Init->getSourceRange()); return true; } case Expr::ConditionalOperatorClass: { // FIXME: Should we pedwarn here? const ConditionalOperator *Exp = cast(Init); if (!Exp->getCond()->getType()->isArithmeticType()) { Diag(Init->getExprLoc(), diag::err_init_element_not_constant, Init->getSourceRange()); return true; } if (CheckArithmeticConstantExpression(Exp->getCond())) return true; if (Exp->getLHS() && CheckAddressConstantExpression(Exp->getLHS())) return true; return CheckAddressConstantExpression(Exp->getRHS()); } case Expr::AddrLabelExprClass: return false; } } bool Sema::CheckArithmeticConstantExpression(const Expr* Init) { switch (Init->getStmtClass()) { default: Diag(Init->getExprLoc(), diag::err_init_element_not_constant, Init->getSourceRange()); return true; case Expr::ParenExprClass: { const ParenExpr* PE = cast(Init); return CheckArithmeticConstantExpression(PE->getSubExpr()); } case Expr::FloatingLiteralClass: case Expr::IntegerLiteralClass: case Expr::CharacterLiteralClass: case Expr::ImaginaryLiteralClass: case Expr::TypesCompatibleExprClass: case Expr::CXXBoolLiteralExprClass: return false; case Expr::CallExprClass: { const CallExpr *CE = cast(Init); if (CE->isBuiltinConstantExpr()) return false; Diag(Init->getExprLoc(), diag::err_init_element_not_constant, Init->getSourceRange()); return true; } case Expr::DeclRefExprClass: { const Decl *D = cast(Init)->getDecl(); if (isa(D)) return false; Diag(Init->getExprLoc(), diag::err_init_element_not_constant, Init->getSourceRange()); return true; } case Expr::CompoundLiteralExprClass: // Allow "(vector type){2,4}"; normal C constraints don't allow this, // but vectors are allowed to be magic. if (Init->getType()->isVectorType()) return false; Diag(Init->getExprLoc(), diag::err_init_element_not_constant, Init->getSourceRange()); return true; case Expr::UnaryOperatorClass: { const UnaryOperator *Exp = cast(Init); switch (Exp->getOpcode()) { // Address, indirect, pre/post inc/dec, etc are not valid constant exprs. // See C99 6.6p3. default: Diag(Init->getExprLoc(), diag::err_init_element_not_constant, Init->getSourceRange()); return true; case UnaryOperator::SizeOf: case UnaryOperator::AlignOf: case UnaryOperator::OffsetOf: // sizeof(E) is a constantexpr if and only if E is not evaluted. // See C99 6.5.3.4p2 and 6.6p3. if (Exp->getSubExpr()->getType()->isConstantSizeType()) return false; Diag(Init->getExprLoc(), diag::err_init_element_not_constant, Init->getSourceRange()); return true; case UnaryOperator::Extension: case UnaryOperator::LNot: case UnaryOperator::Plus: case UnaryOperator::Minus: case UnaryOperator::Not: return CheckArithmeticConstantExpression(Exp->getSubExpr()); } } case Expr::SizeOfAlignOfTypeExprClass: { const SizeOfAlignOfTypeExpr *Exp = cast(Init); // Special check for void types, which are allowed as an extension if (Exp->getArgumentType()->isVoidType()) return false; // alignof always evaluates to a constant. // FIXME: is sizeof(int[3.0]) a constant expression? if (Exp->isSizeOf() && !Exp->getArgumentType()->isConstantSizeType()) { Diag(Init->getExprLoc(), diag::err_init_element_not_constant, Init->getSourceRange()); return true; } return false; } case Expr::BinaryOperatorClass: { const BinaryOperator *Exp = cast(Init); if (Exp->getLHS()->getType()->isArithmeticType() && Exp->getRHS()->getType()->isArithmeticType()) { return CheckArithmeticConstantExpression(Exp->getLHS()) || CheckArithmeticConstantExpression(Exp->getRHS()); } Diag(Init->getExprLoc(), diag::err_init_element_not_constant, Init->getSourceRange()); return true; } case Expr::ImplicitCastExprClass: case Expr::CastExprClass: { const Expr *SubExpr; if (const CastExpr *C = dyn_cast(Init)) { SubExpr = C->getSubExpr(); } else { SubExpr = cast(Init)->getSubExpr(); } if (SubExpr->getType()->isArithmeticType()) return CheckArithmeticConstantExpression(SubExpr); Diag(Init->getExprLoc(), diag::err_init_element_not_constant, Init->getSourceRange()); return true; } case Expr::ConditionalOperatorClass: { const ConditionalOperator *Exp = cast(Init); if (CheckArithmeticConstantExpression(Exp->getCond())) return true; if (Exp->getLHS() && CheckArithmeticConstantExpression(Exp->getLHS())) return true; return CheckArithmeticConstantExpression(Exp->getRHS()); } } } bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { // Look through CXXDefaultArgExprs; they have no meaning in this context. if (CXXDefaultArgExpr* DAE = dyn_cast(Init)) return CheckForConstantInitializer(DAE->getExpr(), DclT); if (Init->getType()->isReferenceType()) { // FIXME: Work out how the heck reference types work return false; #if 0 // A reference is constant if the address of the expression // is constant // We look through initlists here to simplify // CheckAddressConstantExpressionLValue. if (InitListExpr *Exp = dyn_cast(Init)) { assert(Exp->getNumInits() > 0 && "Refernce initializer cannot be empty"); Init = Exp->getInit(0); } return CheckAddressConstantExpressionLValue(Init); #endif } if (InitListExpr *Exp = dyn_cast(Init)) { unsigned numInits = Exp->getNumInits(); for (unsigned i = 0; i < numInits; i++) { // FIXME: Need to get the type of the declaration for C++, // because it could be a reference? if (CheckForConstantInitializer(Exp->getInit(i), Exp->getInit(i)->getType())) return true; } return false; } if (Init->isNullPointerConstant(Context)) return false; if (Init->getType()->isArithmeticType()) { QualType InitTy = Init->getType().getCanonicalType().getUnqualifiedType(); if (InitTy == Context.BoolTy) { // Special handling for pointers implicitly cast to bool; // (e.g. "_Bool rr = &rr;"). This is only legal at the top level. if (ImplicitCastExpr* ICE = dyn_cast(Init)) { Expr* SubE = ICE->getSubExpr(); if (SubE->getType()->isPointerType() || SubE->getType()->isArrayType() || SubE->getType()->isFunctionType()) { return CheckAddressConstantExpression(Init); } } } else if (InitTy->isIntegralType()) { Expr* SubE = 0; if (ImplicitCastExpr* ICE = dyn_cast(Init)) SubE = ICE->getSubExpr(); else if (CastExpr* CE = dyn_cast(Init)) SubE = CE->getSubExpr(); // Special check for pointer cast to int; we allow as an extension // an address constant cast to an integer if the integer // is of an appropriate width (this sort of code is apparently used // in some places). // FIXME: Add pedwarn? // FIXME: Don't allow bitfields here! Need the FieldDecl for that. if (SubE && (SubE->getType()->isPointerType() || SubE->getType()->isArrayType() || SubE->getType()->isFunctionType())) { unsigned IntWidth = Context.getTypeSize(Init->getType()); unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); if (IntWidth >= PointerWidth) return CheckAddressConstantExpression(Init); } } return CheckArithmeticConstantExpression(Init); } if (Init->getType()->isPointerType()) return CheckAddressConstantExpression(Init); // An array type at the top level that isn't an init-list must // be a string literal if (Init->getType()->isArrayType()) return false; Diag(Init->getExprLoc(), diag::err_init_element_not_constant, Init->getSourceRange()); return true; } void Sema::AddInitializerToDecl(DeclTy *dcl, ExprTy *init) { Decl *RealDecl = static_cast(dcl); Expr *Init = static_cast(init); assert(Init && "missing initializer"); // If there is no declaration, there was an error parsing it. Just ignore // the initializer. if (RealDecl == 0) { delete Init; return; } VarDecl *VDecl = dyn_cast(RealDecl); if (!VDecl) { Diag(dyn_cast(RealDecl)->getLocation(), diag::err_illegal_initializer); RealDecl->setInvalidDecl(); return; } // Get the decls type and save a reference for later, since // CheckInitializerTypes may change it. QualType DclT = VDecl->getType(), SavT = DclT; if (VDecl->isBlockVarDecl()) { VarDecl::StorageClass SC = VDecl->getStorageClass(); if (SC == VarDecl::Extern) { // C99 6.7.8p5 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); VDecl->setInvalidDecl(); } else if (!VDecl->isInvalidDecl()) { if (CheckInitializerTypes(Init, DclT)) VDecl->setInvalidDecl(); if (SC == VarDecl::Static) // C99 6.7.8p4. CheckForConstantInitializer(Init, DclT); } } else if (VDecl->isFileVarDecl()) { if (VDecl->getStorageClass() == VarDecl::Extern) Diag(VDecl->getLocation(), diag::warn_extern_init); if (!VDecl->isInvalidDecl()) if (CheckInitializerTypes(Init, DclT)) VDecl->setInvalidDecl(); // C99 6.7.8p4. All file scoped initializers need to be constant. CheckForConstantInitializer(Init, DclT); } // If the type changed, it means we had an incomplete type that was // completed by the initializer. For example: // int ary[] = { 1, 3, 5 }; // "ary" transitions from a VariableArrayType to a ConstantArrayType. if (!VDecl->isInvalidDecl() && (DclT != SavT)) { VDecl->setType(DclT); Init->setType(DclT); } // Attach the initializer to the decl. VDecl->setInit(Init); return; } /// The declarators are chained together backwards, reverse the list. Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { // Often we have single declarators, handle them quickly. Decl *GroupDecl = static_cast(group); if (GroupDecl == 0) return 0; ScopedDecl *Group = dyn_cast(GroupDecl); ScopedDecl *NewGroup = 0; if (Group->getNextDeclarator() == 0) NewGroup = Group; else { // reverse the list. while (Group) { ScopedDecl *Next = Group->getNextDeclarator(); Group->setNextDeclarator(NewGroup); NewGroup = Group; Group = Next; } } // Perform semantic analysis that depends on having fully processed both // the declarator and initializer. for (ScopedDecl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { VarDecl *IDecl = dyn_cast(ID); if (!IDecl) continue; QualType T = IDecl->getType(); // C99 6.7.5.2p2: If an identifier is declared to be an object with // static storage duration, it shall not have a variable length array. if ((IDecl->isFileVarDecl() || IDecl->isBlockVarDecl()) && IDecl->getStorageClass() == VarDecl::Static) { if (T->getAsVariableArrayType()) { Diag(IDecl->getLocation(), diag::err_typecheck_illegal_vla); IDecl->setInvalidDecl(); } } // Block scope. C99 6.7p7: If an identifier for an object is declared with // no linkage (C99 6.2.2p6), the type for the object shall be complete... if (IDecl->isBlockVarDecl() && IDecl->getStorageClass() != VarDecl::Extern) { if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type, T.getAsString()); IDecl->setInvalidDecl(); } } // File scope. C99 6.9.2p2: A declaration of an identifier for and // object that has file scope without an initializer, and without a // storage-class specifier or with the storage-class specifier "static", // constitutes a tentative definition. Note: A tentative definition with // external linkage is valid (C99 6.2.2p5). if (IDecl && !IDecl->getInit() && (IDecl->getStorageClass() == VarDecl::Static || IDecl->getStorageClass() == VarDecl::None)) { if (T->isIncompleteArrayType()) { // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete // array to be completed. Don't issue a diagnostic. } else if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { // C99 6.9.2p3: If the declaration of an identifier for an object is // a tentative definition and has internal linkage (C99 6.2.2p3), the // declared type shall not be an incomplete type. Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type, T.getAsString()); IDecl->setInvalidDecl(); } } } return NewGroup; } /// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() /// to introduce parameters into function prototype scope. Sema::DeclTy * Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { DeclSpec &DS = D.getDeclSpec(); // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && DS.getStorageClassSpec() != DeclSpec::SCS_register) { Diag(DS.getStorageClassSpecLoc(), diag::err_invalid_storage_class_in_func_decl); DS.ClearStorageClassSpecs(); } if (DS.isThreadSpecified()) { Diag(DS.getThreadSpecLoc(), diag::err_invalid_storage_class_in_func_decl); DS.ClearStorageClassSpecs(); } // Check that there are no default arguments inside the type of this // parameter (C++ only). if (getLangOptions().CPlusPlus) CheckExtraCXXDefaultArguments(D); // In this context, we *do not* check D.getInvalidType(). If the declarator // type was invalid, GetTypeForDeclarator() still returns a "valid" type, // though it will not reflect the user specified type. QualType parmDeclType = GetTypeForDeclarator(D, S); assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. // Can this happen for params? We already checked that they don't conflict // among each other. Here they can only shadow globals, which is ok. IdentifierInfo *II = D.getIdentifier(); if (Decl *PrevDecl = LookupDecl(II, Decl::IDNS_Ordinary, S)) { if (S->isDeclScope(PrevDecl)) { Diag(D.getIdentifierLoc(), diag::err_param_redefinition, dyn_cast(PrevDecl)->getName()); // Recover by removing the name II = 0; D.SetIdentifier(0, D.getIdentifierLoc()); } } // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). // Doing the promotion here has a win and a loss. The win is the type for // both Decl's and DeclRefExpr's will match (a convenient invariant for the // code generator). The loss is the orginal type isn't preserved. For example: // // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" // int blockvardecl[5]; // sizeof(parmvardecl); // size == 4 // sizeof(blockvardecl); // size == 20 // } // // For expressions, all implicit conversions are captured using the // ImplicitCastExpr AST node (we have no such mechanism for Decl's). // // FIXME: If a source translation tool needs to see the original type, then // we need to consider storing both types (in ParmVarDecl)... // if (parmDeclType->isArrayType()) { // int x[restrict 4] -> int *restrict parmDeclType = Context.getArrayDecayedType(parmDeclType); } else if (parmDeclType->isFunctionType()) parmDeclType = Context.getPointerType(parmDeclType); ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, parmDeclType, VarDecl::None, 0, 0); if (D.getInvalidType()) New->setInvalidDecl(); if (II) PushOnScopeChains(New, S); HandleDeclAttributes(New, D.getDeclSpec().getAttributes(), D.getAttributes()); return New; } Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { assert(CurFunctionDecl == 0 && "Function parsing confused"); assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && "Not a function declarator!"); DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' // for a K&R function. if (!FTI.hasPrototype) { for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { if (FTI.ArgInfo[i].Param == 0) { Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared, FTI.ArgInfo[i].Ident->getName()); // Implicitly declare the argument as type 'int' for lack of a better // type. DeclSpec DS; const char* PrevSpec; // unused DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, PrevSpec); Declarator ParamD(DS, Declarator::KNRTypeListContext); ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); FTI.ArgInfo[i].Param = ActOnParamDeclarator(FnBodyScope, ParamD); } } // Since this is a function definition, act as though we have information // about the arguments. if (FTI.NumArgs) FTI.hasPrototype = true; } else { // FIXME: Diagnose arguments without names in C. } Scope *GlobalScope = FnBodyScope->getParent(); // See if this is a redefinition. Decl *PrevDcl = LookupDecl(D.getIdentifier(), Decl::IDNS_Ordinary, GlobalScope); if (PrevDcl && IdResolver.isDeclInScope(PrevDcl, CurContext)) { if (FunctionDecl *FD = dyn_cast(PrevDcl)) { const FunctionDecl *Definition; if (FD->getBody(Definition)) { Diag(D.getIdentifierLoc(), diag::err_redefinition, D.getIdentifier()->getName()); Diag(Definition->getLocation(), diag::err_previous_definition); } } } Decl *decl = static_cast(ActOnDeclarator(GlobalScope, D, 0)); FunctionDecl *FD = cast(decl); CurFunctionDecl = FD; PushDeclContext(FD); // Check the validity of our function parameters CheckParmsForFunctionDef(FD); // Introduce our parameters into the function scope for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { ParmVarDecl *Param = FD->getParamDecl(p); // If this has an identifier, add it to the scope stack. if (Param->getIdentifier()) PushOnScopeChains(Param, FnBodyScope); } return FD; } Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtTy *Body) { Decl *dcl = static_cast(D); if (FunctionDecl *FD = dyn_cast(dcl)) { FD->setBody((Stmt*)Body); assert(FD == CurFunctionDecl && "Function parsing confused"); CurFunctionDecl = 0; } else if (ObjCMethodDecl *MD = dyn_cast(dcl)) { MD->setBody((Stmt*)Body); CurMethodDecl = 0; } PopDeclContext(); // Verify and clean out per-function state. // Check goto/label use. for (llvm::DenseMap::iterator I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { // Verify that we have no forward references left. If so, there was a goto // or address of a label taken, but no definition of it. Label fwd // definitions are indicated with a null substmt. if (I->second->getSubStmt() == 0) { LabelStmt *L = I->second; // Emit error. Diag(L->getIdentLoc(), diag::err_undeclared_label_use, L->getName()); // At this point, we have gotos that use the bogus label. Stitch it into // the function body so that they aren't leaked and that the AST is well // formed. if (Body) { L->setSubStmt(new NullStmt(L->getIdentLoc())); cast((Stmt*)Body)->push_back(L); } else { // The whole function wasn't parsed correctly, just delete this. delete L; } } } LabelMap.clear(); return D; } /// ImplicitlyDefineFunction - An undeclared identifier was used in a function /// call, forming a call to an implicitly defined function (per C99 6.5.1p2). ScopedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, IdentifierInfo &II, Scope *S) { // Extension in C99. Legal in C90, but warn about it. if (getLangOptions().C99) Diag(Loc, diag::ext_implicit_function_decl, II.getName()); else Diag(Loc, diag::warn_implicit_function_decl, II.getName()); // FIXME: handle stuff like: // void foo() { extern float X(); } // void bar() { X(); } <-- implicit decl for X in another scope. // Set a Declarator for the implicit definition: int foo(); const char *Dummy; DeclSpec DS; bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); Error = Error; // Silence warning. assert(!Error && "Error setting up implicit decl!"); Declarator D(DS, Declarator::BlockContext); D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, 0, 0, Loc)); D.SetIdentifier(&II, Loc); // Insert this function into translation-unit scope. DeclContext *PrevDC = CurContext; CurContext = Context.getTranslationUnitDecl(); FunctionDecl *FD = dyn_cast(static_cast(ActOnDeclarator(TUScope, D, 0))); FD->setImplicit(); CurContext = PrevDC; return FD; } TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, ScopedDecl *LastDeclarator) { assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); // Scope manipulation handled by caller. TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, D.getIdentifierLoc(), D.getIdentifier(), T, LastDeclarator); if (D.getInvalidType()) NewTD->setInvalidDecl(); return NewTD; } /// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the /// former case, Name will be non-null. In the later case, Name will be null. /// TagType indicates what kind of tag this is. TK indicates whether this is a /// reference/declaration/definition of a tag. Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagType, TagKind TK, SourceLocation KWLoc, IdentifierInfo *Name, SourceLocation NameLoc, AttributeList *Attr) { // If this is a use of an existing tag, it must have a name. assert((Name != 0 || TK == TK_Definition) && "Nameless record must be a definition!"); Decl::Kind Kind; switch (TagType) { default: assert(0 && "Unknown tag type!"); case DeclSpec::TST_struct: Kind = Decl::Struct; break; case DeclSpec::TST_union: Kind = Decl::Union; break; case DeclSpec::TST_class: Kind = Decl::Class; break; case DeclSpec::TST_enum: Kind = Decl::Enum; break; } // If this is a named struct, check to see if there was a previous forward // declaration or definition. // Use ScopedDecl instead of TagDecl, because a NamespaceDecl may come up. if (ScopedDecl *PrevDecl = dyn_cast_or_null(LookupDecl(Name, Decl::IDNS_Tag, S))) { assert((isa(PrevDecl) || isa(PrevDecl)) && "unexpected Decl type"); if (TagDecl *PrevTagDecl = dyn_cast(PrevDecl)) { // If this is a use of a previous tag, or if the tag is already declared in // the same scope (so that the definition/declaration completes or // rementions the tag), reuse the decl. if (TK == TK_Reference || IdResolver.isDeclInScope(PrevDecl, CurContext, S)) { // Make sure that this wasn't declared as an enum and now used as a struct // or something similar. if (PrevDecl->getKind() != Kind) { Diag(KWLoc, diag::err_use_with_wrong_tag, Name->getName()); Diag(PrevDecl->getLocation(), diag::err_previous_use); } // If this is a use or a forward declaration, we're good. if (TK != TK_Definition) return PrevDecl; // Diagnose attempts to redefine a tag. if (PrevTagDecl->isDefinition()) { Diag(NameLoc, diag::err_redefinition, Name->getName()); Diag(PrevDecl->getLocation(), diag::err_previous_definition); // If this is a redefinition, recover by making this struct be // anonymous, which will make any later references get the previous // definition. Name = 0; } else { // Okay, this is definition of a previously declared or referenced tag. // Move the location of the decl to be the definition site. PrevDecl->setLocation(NameLoc); return PrevDecl; } } // If we get here, this is a definition of a new struct type in a nested // scope, e.g. "struct foo; void bar() { struct foo; }", just create a new // type. } else { // The tag name clashes with a namespace name, issue an error and recover // by making this tag be anonymous. Diag(NameLoc, diag::err_redefinition_different_kind, Name->getName()); Diag(PrevDecl->getLocation(), diag::err_previous_definition); Name = 0; } } // If there is an identifier, use the location of the identifier as the // location of the decl, otherwise use the location of the struct/union // keyword. SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; // Otherwise, if this is the first time we've seen this tag, create the decl. TagDecl *New; switch (Kind) { default: assert(0 && "Unknown tag kind!"); case Decl::Enum: // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: // enum X { A, B, C } D; D should chain to X. New = EnumDecl::Create(Context, CurContext, Loc, Name, 0); // If this is an undefined enum, warn. if (TK != TK_Definition) Diag(Loc, diag::ext_forward_ref_enum); break; case Decl::Union: case Decl::Struct: case Decl::Class: // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: // struct X { int A; } D; D should chain to X. New = RecordDecl::Create(Context, Kind, CurContext, Loc, Name, 0); break; } // If this has an identifier, add it to the scope stack. if (Name) { // The scope passed in may not be a decl scope. Zip up the scope tree until // we find one that is. while ((S->getFlags() & Scope::DeclScope) == 0) S = S->getParent(); // Add it to the decl chain. PushOnScopeChains(New, S); } HandleDeclAttributes(New, Attr, 0); return New; } /// ActOnField - Each field of a struct/union/class is passed into this in order /// to create a FieldDecl object for it. Sema::DeclTy *Sema::ActOnField(Scope *S, SourceLocation DeclStart, Declarator &D, ExprTy *BitfieldWidth) { IdentifierInfo *II = D.getIdentifier(); Expr *BitWidth = (Expr*)BitfieldWidth; SourceLocation Loc = DeclStart; if (II) Loc = D.getIdentifierLoc(); // FIXME: Unnamed fields can be handled in various different ways, for // example, unnamed unions inject all members into the struct namespace! if (BitWidth) { // TODO: Validate. //printf("WARNING: BITFIELDS IGNORED!\n"); // 6.7.2.1p3 // 6.7.2.1p4 } else { // Not a bitfield. // validate II. } QualType T = GetTypeForDeclarator(D, S); assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); bool InvalidDecl = false; // C99 6.7.2.1p8: A member of a structure or union may have any type other // than a variably modified type. if (T->isVariablyModifiedType()) { // FIXME: This diagnostic needs work Diag(Loc, diag::err_typecheck_illegal_vla, Loc); InvalidDecl = true; } // FIXME: Chain fielddecls together. FieldDecl *NewFD = FieldDecl::Create(Context, Loc, II, T, BitWidth); HandleDeclAttributes(NewFD, D.getDeclSpec().getAttributes(), D.getAttributes()); if (D.getInvalidType() || InvalidDecl) NewFD->setInvalidDecl(); return NewFD; } /// TranslateIvarVisibility - Translate visibility from a token ID to an /// AST enum value. static ObjCIvarDecl::AccessControl TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { switch (ivarVisibility) { case tok::objc_private: return ObjCIvarDecl::Private; case tok::objc_public: return ObjCIvarDecl::Public; case tok::objc_protected: return ObjCIvarDecl::Protected; case tok::objc_package: return ObjCIvarDecl::Package; default: assert(false && "Unknown visitibility kind"); } } /// ActOnIvar - Each ivar field of an objective-c class is passed into this /// in order to create an IvarDecl object for it. Sema::DeclTy *Sema::ActOnIvar(Scope *S, SourceLocation DeclStart, Declarator &D, ExprTy *BitfieldWidth, tok::ObjCKeywordKind Visibility) { IdentifierInfo *II = D.getIdentifier(); Expr *BitWidth = (Expr*)BitfieldWidth; SourceLocation Loc = DeclStart; if (II) Loc = D.getIdentifierLoc(); // FIXME: Unnamed fields can be handled in various different ways, for // example, unnamed unions inject all members into the struct namespace! if (BitWidth) { // TODO: Validate. //printf("WARNING: BITFIELDS IGNORED!\n"); // 6.7.2.1p3 // 6.7.2.1p4 } else { // Not a bitfield. // validate II. } QualType T = GetTypeForDeclarator(D, S); assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); bool InvalidDecl = false; // C99 6.7.2.1p8: A member of a structure or union may have any type other // than a variably modified type. if (T->isVariablyModifiedType()) { // FIXME: This diagnostic needs work Diag(Loc, diag::err_typecheck_illegal_vla, Loc); InvalidDecl = true; } ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, Loc, II, T); HandleDeclAttributes(NewID, D.getDeclSpec().getAttributes(), D.getAttributes()); if (D.getInvalidType() || InvalidDecl) NewID->setInvalidDecl(); // If we have visibility info, make sure the AST is set accordingly. if (Visibility != tok::objc_not_keyword) NewID->setAccessControl(TranslateIvarVisibility(Visibility)); return NewID; } void Sema::ActOnFields(Scope* S, SourceLocation RecLoc, DeclTy *RecDecl, DeclTy **Fields, unsigned NumFields, SourceLocation LBrac, SourceLocation RBrac) { Decl *EnclosingDecl = static_cast(RecDecl); assert(EnclosingDecl && "missing record or interface decl"); RecordDecl *Record = dyn_cast(EnclosingDecl); if (Record && Record->isDefinition()) { // Diagnose code like: // struct S { struct S {} X; }; // We discover this when we complete the outer S. Reject and ignore the // outer S. Diag(Record->getLocation(), diag::err_nested_redefinition, Record->getKindName()); Diag(RecLoc, diag::err_previous_definition); Record->setInvalidDecl(); return; } // Verify that all the fields are okay. unsigned NumNamedMembers = 0; llvm::SmallVector RecFields; llvm::SmallSet FieldIDs; for (unsigned i = 0; i != NumFields; ++i) { FieldDecl *FD = cast_or_null(static_cast(Fields[i])); assert(FD && "missing field decl"); // Remember all fields. RecFields.push_back(FD); // Get the type for the field. Type *FDTy = FD->getType().getTypePtr(); // C99 6.7.2.1p2 - A field may not be a function type. if (FDTy->isFunctionType()) { Diag(FD->getLocation(), diag::err_field_declared_as_function, FD->getName()); FD->setInvalidDecl(); EnclosingDecl->setInvalidDecl(); continue; } // C99 6.7.2.1p2 - A field may not be an incomplete type except... if (FDTy->isIncompleteType()) { if (!Record) { // Incomplete ivar type is always an error. Diag(FD->getLocation(), diag::err_field_incomplete, FD->getName()); FD->setInvalidDecl(); EnclosingDecl->setInvalidDecl(); continue; } if (i != NumFields-1 || // ... that the last member ... Record->getKind() != Decl::Struct || // ... of a structure ... !FDTy->isArrayType()) { //... may have incomplete array type. Diag(FD->getLocation(), diag::err_field_incomplete, FD->getName()); FD->setInvalidDecl(); EnclosingDecl->setInvalidDecl(); continue; } if (NumNamedMembers < 1) { //... must have more than named member ... Diag(FD->getLocation(), diag::err_flexible_array_empty_struct, FD->getName()); FD->setInvalidDecl(); EnclosingDecl->setInvalidDecl(); continue; } // Okay, we have a legal flexible array member at the end of the struct. if (Record) Record->setHasFlexibleArrayMember(true); } /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the /// field of another structure or the element of an array. if (const RecordType *FDTTy = FDTy->getAsRecordType()) { if (FDTTy->getDecl()->hasFlexibleArrayMember()) { // If this is a member of a union, then entire union becomes "flexible". if (Record && Record->getKind() == Decl::Union) { Record->setHasFlexibleArrayMember(true); } else { // If this is a struct/class and this is not the last element, reject // it. Note that GCC supports variable sized arrays in the middle of // structures. if (i != NumFields-1) { Diag(FD->getLocation(), diag::err_variable_sized_type_in_struct, FD->getName()); FD->setInvalidDecl(); EnclosingDecl->setInvalidDecl(); continue; } // We support flexible arrays at the end of structs in other structs // as an extension. Diag(FD->getLocation(), diag::ext_flexible_array_in_struct, FD->getName()); if (Record) Record->setHasFlexibleArrayMember(true); } } } /// A field cannot be an Objective-c object if (FDTy->isObjCInterfaceType()) { Diag(FD->getLocation(), diag::err_statically_allocated_object, FD->getName()); FD->setInvalidDecl(); EnclosingDecl->setInvalidDecl(); continue; } // Keep track of the number of named members. if (IdentifierInfo *II = FD->getIdentifier()) { // Detect duplicate member names. if (!FieldIDs.insert(II)) { Diag(FD->getLocation(), diag::err_duplicate_member, II->getName()); // Find the previous decl. SourceLocation PrevLoc; for (unsigned i = 0, e = RecFields.size(); ; ++i) { assert(i != e && "Didn't find previous def!"); if (RecFields[i]->getIdentifier() == II) { PrevLoc = RecFields[i]->getLocation(); break; } } Diag(PrevLoc, diag::err_previous_definition); FD->setInvalidDecl(); EnclosingDecl->setInvalidDecl(); continue; } ++NumNamedMembers; } } // Okay, we successfully defined 'Record'. if (Record) { Record->defineBody(&RecFields[0], RecFields.size()); Consumer.HandleTagDeclDefinition(Record); } else { ObjCIvarDecl **ClsFields = reinterpret_cast(&RecFields[0]); if (ObjCInterfaceDecl *ID = dyn_cast(EnclosingDecl)) ID->addInstanceVariablesToClass(ClsFields, RecFields.size(), RBrac); else if (ObjCImplementationDecl *IMPDecl = dyn_cast(EnclosingDecl)) { assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); IMPDecl->ObjCAddInstanceVariablesToClassImpl(ClsFields, RecFields.size()); CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); } } } Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, DeclTy *lastEnumConst, SourceLocation IdLoc, IdentifierInfo *Id, SourceLocation EqualLoc, ExprTy *val) { EnumDecl *TheEnumDecl = cast(static_cast(theEnumDecl)); EnumConstantDecl *LastEnumConst = cast_or_null(static_cast(lastEnumConst)); Expr *Val = static_cast(val); // The scope passed in may not be a decl scope. Zip up the scope tree until // we find one that is. while ((S->getFlags() & Scope::DeclScope) == 0) S = S->getParent(); // Verify that there isn't already something declared with this name in this // scope. if (Decl *PrevDecl = LookupDecl(Id, Decl::IDNS_Ordinary, S)) { if (IdResolver.isDeclInScope(PrevDecl, CurContext, S)) { if (isa(PrevDecl)) Diag(IdLoc, diag::err_redefinition_of_enumerator, Id->getName()); else Diag(IdLoc, diag::err_redefinition, Id->getName()); Diag(PrevDecl->getLocation(), diag::err_previous_definition); delete Val; return 0; } } llvm::APSInt EnumVal(32); QualType EltTy; if (Val) { // Make sure to promote the operand type to int. UsualUnaryConversions(Val); // C99 6.7.2.2p2: Make sure we have an integer constant expression. SourceLocation ExpLoc; if (!Val->isIntegerConstantExpr(EnumVal, Context, &ExpLoc)) { Diag(ExpLoc, diag::err_enum_value_not_integer_constant_expr, Id->getName()); delete Val; Val = 0; // Just forget about it. } else { EltTy = Val->getType(); } } if (!Val) { if (LastEnumConst) { // Assign the last value + 1. EnumVal = LastEnumConst->getInitVal(); ++EnumVal; // Check for overflow on increment. if (EnumVal < LastEnumConst->getInitVal()) Diag(IdLoc, diag::warn_enum_value_overflow); EltTy = LastEnumConst->getType(); } else { // First value, set to zero. EltTy = Context.IntTy; EnumVal.zextOrTrunc(static_cast(Context.getTypeSize(EltTy))); } } EnumConstantDecl *New = EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, Val, EnumVal, LastEnumConst); // Register this decl in the current scope stack. PushOnScopeChains(New, S); return New; } void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, DeclTy **Elements, unsigned NumElements) { EnumDecl *Enum = cast(static_cast(EnumDeclX)); assert(!Enum->isDefinition() && "Enum redefinitions can't reach here"); // TODO: If the result value doesn't fit in an int, it must be a long or long // long value. ISO C does not support this, but GCC does as an extension, // emit a warning. unsigned IntWidth = Context.Target.getIntWidth(); // Verify that all the values are okay, compute the size of the values, and // reverse the list. unsigned NumNegativeBits = 0; unsigned NumPositiveBits = 0; // Keep track of whether all elements have type int. bool AllElementsInt = true; EnumConstantDecl *EltList = 0; for (unsigned i = 0; i != NumElements; ++i) { EnumConstantDecl *ECD = cast_or_null(static_cast(Elements[i])); if (!ECD) continue; // Already issued a diagnostic. // If the enum value doesn't fit in an int, emit an extension warning. const llvm::APSInt &InitVal = ECD->getInitVal(); assert(InitVal.getBitWidth() >= IntWidth && "Should have promoted value to int"); if (InitVal.getBitWidth() > IntWidth) { llvm::APSInt V(InitVal); V.trunc(IntWidth); V.extend(InitVal.getBitWidth()); if (V != InitVal) Diag(ECD->getLocation(), diag::ext_enum_value_not_int, InitVal.toString()); } // Keep track of the size of positive and negative values. if (InitVal.isUnsigned() || InitVal.isNonNegative()) NumPositiveBits = std::max(NumPositiveBits, (unsigned)InitVal.getActiveBits()); else NumNegativeBits = std::max(NumNegativeBits, (unsigned)InitVal.getMinSignedBits()); // Keep track of whether every enum element has type int (very commmon). if (AllElementsInt) AllElementsInt = ECD->getType() == Context.IntTy; ECD->setNextDeclarator(EltList); EltList = ECD; } // Figure out the type that should be used for this enum. // FIXME: Support attribute(packed) on enums and -fshort-enums. QualType BestType; unsigned BestWidth; if (NumNegativeBits) { // If there is a negative value, figure out the smallest integer type (of // int/long/longlong) that fits. if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { BestType = Context.IntTy; BestWidth = IntWidth; } else { BestWidth = Context.Target.getLongWidth(); if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) BestType = Context.LongTy; else { BestWidth = Context.Target.getLongLongWidth(); if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) Diag(Enum->getLocation(), diag::warn_enum_too_large); BestType = Context.LongLongTy; } } } else { // If there is no negative value, figure out which of uint, ulong, ulonglong // fits. if (NumPositiveBits <= IntWidth) { BestType = Context.UnsignedIntTy; BestWidth = IntWidth; } else if (NumPositiveBits <= (BestWidth = Context.Target.getLongWidth())) { BestType = Context.UnsignedLongTy; } else { BestWidth = Context.Target.getLongLongWidth(); assert(NumPositiveBits <= BestWidth && "How could an initializer get larger than ULL?"); BestType = Context.UnsignedLongLongTy; } } // Loop over all of the enumerator constants, changing their types to match // the type of the enum if needed. for (unsigned i = 0; i != NumElements; ++i) { EnumConstantDecl *ECD = cast_or_null(static_cast(Elements[i])); if (!ECD) continue; // Already issued a diagnostic. // Standard C says the enumerators have int type, but we allow, as an // extension, the enumerators to be larger than int size. If each // enumerator value fits in an int, type it as an int, otherwise type it the // same as the enumerator decl itself. This means that in "enum { X = 1U }" // that X has type 'int', not 'unsigned'. if (ECD->getType() == Context.IntTy) { // Make sure the init value is signed. llvm::APSInt IV = ECD->getInitVal(); IV.setIsSigned(true); ECD->setInitVal(IV); continue; // Already int type. } // Determine whether the value fits into an int. llvm::APSInt InitVal = ECD->getInitVal(); bool FitsInInt; if (InitVal.isUnsigned() || !InitVal.isNegative()) FitsInInt = InitVal.getActiveBits() < IntWidth; else FitsInInt = InitVal.getMinSignedBits() <= IntWidth; // If it fits into an integer type, force it. Otherwise force it to match // the enum decl type. QualType NewTy; unsigned NewWidth; bool NewSign; if (FitsInInt) { NewTy = Context.IntTy; NewWidth = IntWidth; NewSign = true; } else if (ECD->getType() == BestType) { // Already the right type! continue; } else { NewTy = BestType; NewWidth = BestWidth; NewSign = BestType->isSignedIntegerType(); } // Adjust the APSInt value. InitVal.extOrTrunc(NewWidth); InitVal.setIsSigned(NewSign); ECD->setInitVal(InitVal); // Adjust the Expr initializer and type. ECD->setInitExpr(new ImplicitCastExpr(NewTy, ECD->getInitExpr())); ECD->setType(NewTy); } Enum->defineElements(EltList, BestType); Consumer.HandleTagDeclDefinition(Enum); } Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, ExprTy *expr) { StringLiteral *AsmString = cast((Expr*)expr); return FileScopeAsmDecl::Create(Context, Loc, AsmString); } Sema::DeclTy* Sema::ActOnLinkageSpec(SourceLocation Loc, SourceLocation LBrace, SourceLocation RBrace, const char *Lang, unsigned StrSize, DeclTy *D) { LinkageSpecDecl::LanguageIDs Language; Decl *dcl = static_cast(D); if (strncmp(Lang, "\"C\"", StrSize) == 0) Language = LinkageSpecDecl::lang_c; else if (strncmp(Lang, "\"C++\"", StrSize) == 0) Language = LinkageSpecDecl::lang_cxx; else { Diag(Loc, diag::err_bad_language); return 0; } // FIXME: Add all the various semantics of linkage specifications return LinkageSpecDecl::Create(Context, Loc, Language, dcl); } void Sema::HandleDeclAttribute(Decl *New, AttributeList *Attr) { switch (Attr->getKind()) { case AttributeList::AT_vector_size: if (ValueDecl *vDecl = dyn_cast(New)) { QualType newType = HandleVectorTypeAttribute(vDecl->getType(), Attr); if (!newType.isNull()) // install the new vector type into the decl vDecl->setType(newType); } if (TypedefDecl *tDecl = dyn_cast(New)) { QualType newType = HandleVectorTypeAttribute(tDecl->getUnderlyingType(), Attr); if (!newType.isNull()) // install the new vector type into the decl tDecl->setUnderlyingType(newType); } break; case AttributeList::AT_ext_vector_type: if (TypedefDecl *tDecl = dyn_cast(New)) HandleExtVectorTypeAttribute(tDecl, Attr); else Diag(Attr->getLoc(), diag::err_typecheck_ext_vector_not_typedef); break; case AttributeList::AT_address_space: if (TypedefDecl *tDecl = dyn_cast(New)) { QualType newType = HandleAddressSpaceTypeAttribute( tDecl->getUnderlyingType(), Attr); tDecl->setUnderlyingType(newType); } else if (ValueDecl *vDecl = dyn_cast(New)) { QualType newType = HandleAddressSpaceTypeAttribute(vDecl->getType(), Attr); // install the new addr spaced type into the decl vDecl->setType(newType); } break; case AttributeList::AT_mode: if (TypedefDecl *tDecl = dyn_cast(New)) { QualType newType = HandleModeTypeAttribute(tDecl->getUnderlyingType(), Attr); tDecl->setUnderlyingType(newType); } else if (ValueDecl *vDecl = dyn_cast(New)) { QualType newType = HandleModeTypeAttribute(vDecl->getType(), Attr); vDecl->setType(newType); } // FIXME: Diagnostic? break; case AttributeList::AT_deprecated: HandleDeprecatedAttribute(New, Attr); break; case AttributeList::AT_visibility: HandleVisibilityAttribute(New, Attr); break; case AttributeList::AT_weak: HandleWeakAttribute(New, Attr); break; case AttributeList::AT_dllimport: HandleDLLImportAttribute(New, Attr); break; case AttributeList::AT_dllexport: HandleDLLExportAttribute(New, Attr); break; case AttributeList::AT_nothrow: HandleNothrowAttribute(New, Attr); break; case AttributeList::AT_stdcall: HandleStdCallAttribute(New, Attr); break; case AttributeList::AT_fastcall: HandleFastCallAttribute(New, Attr); break; case AttributeList::AT_aligned: HandleAlignedAttribute(New, Attr); break; case AttributeList::AT_packed: HandlePackedAttribute(New, Attr); break; case AttributeList::AT_annotate: HandleAnnotateAttribute(New, Attr); break; case AttributeList::AT_noreturn: HandleNoReturnAttribute(New, Attr); break; case AttributeList::AT_format: HandleFormatAttribute(New, Attr); break; case AttributeList::AT_transparent_union: HandleTransparentUnionAttribute(New, Attr); break; default: #if 0 // TODO: when we have the full set of attributes, warn about unknown ones. Diag(Attr->getLoc(), diag::warn_attribute_ignored, Attr->getName()->getName()); #endif break; } } void Sema::HandleDeclAttributes(Decl *New, AttributeList *declspec_prefix, AttributeList *declarator_postfix) { while (declspec_prefix) { HandleDeclAttribute(New, declspec_prefix); declspec_prefix = declspec_prefix->getNext(); } while (declarator_postfix) { HandleDeclAttribute(New, declarator_postfix); declarator_postfix = declarator_postfix->getNext(); } } void Sema::HandleExtVectorTypeAttribute(TypedefDecl *tDecl, AttributeList *rawAttr) { QualType curType = tDecl->getUnderlyingType(); // check the attribute arguments. if (rawAttr->getNumArgs() != 1) { Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, std::string("1")); return; } Expr *sizeExpr = static_cast(rawAttr->getArg(0)); llvm::APSInt vecSize(32); if (!sizeExpr->isIntegerConstantExpr(vecSize, Context)) { Diag(rawAttr->getLoc(), diag::err_attribute_argument_not_int, "ext_vector_type", sizeExpr->getSourceRange()); return; } // unlike gcc's vector_size attribute, we do not allow vectors to be defined // in conjunction with complex types (pointers, arrays, functions, etc.). Type *canonType = curType.getCanonicalType().getTypePtr(); if (!(canonType->isIntegerType() || canonType->isRealFloatingType())) { Diag(rawAttr->getLoc(), diag::err_attribute_invalid_vector_type, curType.getCanonicalType().getAsString()); return; } // unlike gcc's vector_size attribute, the size is specified as the // number of elements, not the number of bytes. unsigned vectorSize = static_cast(vecSize.getZExtValue()); if (vectorSize == 0) { Diag(rawAttr->getLoc(), diag::err_attribute_zero_size, sizeExpr->getSourceRange()); return; } // Instantiate/Install the vector type, the number of elements is > 0. tDecl->setUnderlyingType(Context.getExtVectorType(curType, vectorSize)); // Remember this typedef decl, we will need it later for diagnostics. ExtVectorDecls.push_back(tDecl); } QualType Sema::HandleVectorTypeAttribute(QualType curType, AttributeList *rawAttr) { // check the attribute arugments. if (rawAttr->getNumArgs() != 1) { Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, std::string("1")); return QualType(); } Expr *sizeExpr = static_cast(rawAttr->getArg(0)); llvm::APSInt vecSize(32); if (!sizeExpr->isIntegerConstantExpr(vecSize, Context)) { Diag(rawAttr->getLoc(), diag::err_attribute_argument_not_int, "vector_size", sizeExpr->getSourceRange()); return QualType(); } // navigate to the base type - we need to provide for vector pointers, // vector arrays, and functions returning vectors. Type *canonType = curType.getCanonicalType().getTypePtr(); if (canonType->isPointerType() || canonType->isArrayType() || canonType->isFunctionType()) { assert(0 && "HandleVector(): Complex type construction unimplemented"); /* FIXME: rebuild the type from the inside out, vectorizing the inner type. do { if (PointerType *PT = dyn_cast(canonType)) canonType = PT->getPointeeType().getTypePtr(); else if (ArrayType *AT = dyn_cast(canonType)) canonType = AT->getElementType().getTypePtr(); else if (FunctionType *FT = dyn_cast(canonType)) canonType = FT->getResultType().getTypePtr(); } while (canonType->isPointerType() || canonType->isArrayType() || canonType->isFunctionType()); */ } // the base type must be integer or float. if (!(canonType->isIntegerType() || canonType->isRealFloatingType())) { Diag(rawAttr->getLoc(), diag::err_attribute_invalid_vector_type, curType.getCanonicalType().getAsString()); return QualType(); } unsigned typeSize = static_cast(Context.getTypeSize(curType)); // vecSize is specified in bytes - convert to bits. unsigned vectorSize = static_cast(vecSize.getZExtValue() * 8); // the vector size needs to be an integral multiple of the type size. if (vectorSize % typeSize) { Diag(rawAttr->getLoc(), diag::err_attribute_invalid_size, sizeExpr->getSourceRange()); return QualType(); } if (vectorSize == 0) { Diag(rawAttr->getLoc(), diag::err_attribute_zero_size, sizeExpr->getSourceRange()); return QualType(); } // Instantiate the vector type, the number of elements is > 0, and not // required to be a power of 2, unlike GCC. return Context.getVectorType(curType, vectorSize/typeSize); } void Sema::HandlePackedAttribute(Decl *d, AttributeList *rawAttr) { // check the attribute arguments. if (rawAttr->getNumArgs() > 0) { Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, std::string("0")); return; } if (TagDecl *TD = dyn_cast(d)) TD->addAttr(new PackedAttr); else if (FieldDecl *FD = dyn_cast(d)) { // If the alignment is less than or equal to 8 bits, the packed attribute // has no effect. if (!FD->getType()->isIncompleteType() && Context.getTypeAlign(FD->getType()) <= 8) Diag(rawAttr->getLoc(), diag::warn_attribute_ignored_for_field_of_type, rawAttr->getName()->getName(), FD->getType().getAsString()); else FD->addAttr(new PackedAttr); } else Diag(rawAttr->getLoc(), diag::warn_attribute_ignored, rawAttr->getName()->getName()); } void Sema::HandleNoReturnAttribute(Decl *d, AttributeList *rawAttr) { // check the attribute arguments. if (rawAttr->getNumArgs() != 0) { Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, std::string("0")); return; } FunctionDecl *Fn = dyn_cast(d); if (!Fn) { Diag(rawAttr->getLoc(), diag::warn_attribute_wrong_decl_type, "noreturn", "function"); return; } d->addAttr(new NoReturnAttr()); } void Sema::HandleDeprecatedAttribute(Decl *d, AttributeList *rawAttr) { // check the attribute arguments. if (rawAttr->getNumArgs() != 0) { Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, std::string("0")); return; } d->addAttr(new DeprecatedAttr()); } void Sema::HandleVisibilityAttribute(Decl *d, AttributeList *rawAttr) { // check the attribute arguments. if (rawAttr->getNumArgs() != 1) { Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, std::string("1")); return; } Expr *Arg = static_cast(rawAttr->getArg(0)); Arg = Arg->IgnoreParenCasts(); StringLiteral *Str = dyn_cast(Arg); if (Str == 0 || Str->isWide()) { Diag(rawAttr->getLoc(), diag::err_attribute_argument_n_not_string, "visibility", std::string("1")); return; } const char *TypeStr = Str->getStrData(); unsigned TypeLen = Str->getByteLength(); VisibilityAttr::VisibilityTypes type; if (TypeLen == 7 && !memcmp(TypeStr, "default", 7)) type = VisibilityAttr::DefaultVisibility; else if (TypeLen == 6 && !memcmp(TypeStr, "hidden", 6)) type = VisibilityAttr::HiddenVisibility; else if (TypeLen == 8 && !memcmp(TypeStr, "internal", 8)) type = VisibilityAttr::HiddenVisibility; // FIXME else if (TypeLen == 9 && !memcmp(TypeStr, "protected", 9)) type = VisibilityAttr::ProtectedVisibility; else { Diag(rawAttr->getLoc(), diag::warn_attribute_type_not_supported, "visibility", TypeStr); return; } d->addAttr(new VisibilityAttr(type)); } void Sema::HandleWeakAttribute(Decl *d, AttributeList *rawAttr) { // check the attribute arguments. if (rawAttr->getNumArgs() != 0) { Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, std::string("0")); return; } d->addAttr(new WeakAttr()); } void Sema::HandleDLLImportAttribute(Decl *d, AttributeList *rawAttr) { // check the attribute arguments. if (rawAttr->getNumArgs() != 0) { Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, std::string("0")); return; } d->addAttr(new DLLImportAttr()); } void Sema::HandleDLLExportAttribute(Decl *d, AttributeList *rawAttr) { // check the attribute arguments. if (rawAttr->getNumArgs() != 0) { Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, std::string("0")); return; } d->addAttr(new DLLExportAttr()); } void Sema::HandleStdCallAttribute(Decl *d, AttributeList *rawAttr) { // check the attribute arguments. if (rawAttr->getNumArgs() != 0) { Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, std::string("0")); return; } d->addAttr(new StdCallAttr()); } void Sema::HandleFastCallAttribute(Decl *d, AttributeList *rawAttr) { // check the attribute arguments. if (rawAttr->getNumArgs() != 0) { Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, std::string("0")); return; } d->addAttr(new FastCallAttr()); } void Sema::HandleNothrowAttribute(Decl *d, AttributeList *rawAttr) { // check the attribute arguments. if (rawAttr->getNumArgs() != 0) { Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, std::string("0")); return; } d->addAttr(new NoThrowAttr()); } static const FunctionTypeProto *getFunctionProto(Decl *d) { QualType Ty; if (ValueDecl *decl = dyn_cast(d)) Ty = decl->getType(); else if (FieldDecl *decl = dyn_cast(d)) Ty = decl->getType(); else if (TypedefDecl* decl = dyn_cast(d)) Ty = decl->getUnderlyingType(); else return 0; if (Ty->isFunctionPointerType()) { const PointerType *PtrTy = Ty->getAsPointerType(); Ty = PtrTy->getPointeeType(); } if (const FunctionType *FnTy = Ty->getAsFunctionType()) return dyn_cast(FnTy->getAsFunctionType()); return 0; } static inline bool isNSStringType(QualType T, ASTContext &Ctx) { if (!T->isPointerType()) return false; T = T->getAsPointerType()->getPointeeType().getCanonicalType(); ObjCInterfaceType* ClsT = dyn_cast(T.getTypePtr()); if (!ClsT) return false; IdentifierInfo* ClsName = ClsT->getDecl()->getIdentifier(); // FIXME: Should we walk the chain of classes? return ClsName == &Ctx.Idents.get("NSString") || ClsName == &Ctx.Idents.get("NSMutableString"); } /// Handle __attribute__((format(type,idx,firstarg))) attributes /// based on http://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html void Sema::HandleFormatAttribute(Decl *d, AttributeList *rawAttr) { if (!rawAttr->getParameterName()) { Diag(rawAttr->getLoc(), diag::err_attribute_argument_n_not_string, "format", std::string("1")); return; } if (rawAttr->getNumArgs() != 2) { Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, std::string("3")); return; } // GCC ignores the format attribute on K&R style function // prototypes, so we ignore it as well const FunctionTypeProto *proto = getFunctionProto(d); if (!proto) { Diag(rawAttr->getLoc(), diag::warn_attribute_wrong_decl_type, "format", "function"); return; } // FIXME: in C++ the implicit 'this' function parameter also counts. // this is needed in order to be compatible with GCC // the index must start in 1 and the limit is numargs+1 unsigned NumArgs = proto->getNumArgs(); unsigned FirstIdx = 1; const char *Format = rawAttr->getParameterName()->getName(); unsigned FormatLen = rawAttr->getParameterName()->getLength(); // Normalize the argument, __foo__ becomes foo. if (FormatLen > 4 && Format[0] == '_' && Format[1] == '_' && Format[FormatLen - 2] == '_' && Format[FormatLen - 1] == '_') { Format += 2; FormatLen -= 4; } bool Supported = false; bool is_NSString = false; bool is_strftime = false; switch (FormatLen) { default: break; case 5: Supported = !memcmp(Format, "scanf", 5); break; case 6: Supported = !memcmp(Format, "printf", 6); break; case 7: Supported = !memcmp(Format, "strfmon", 7); break; case 8: Supported = (is_strftime = !memcmp(Format, "strftime", 8)) || (is_NSString = !memcmp(Format, "NSString", 8)); break; } if (!Supported) { Diag(rawAttr->getLoc(), diag::warn_attribute_type_not_supported, "format", rawAttr->getParameterName()->getName()); return; } // checks for the 2nd argument Expr *IdxExpr = static_cast(rawAttr->getArg(0)); llvm::APSInt Idx(Context.getTypeSize(IdxExpr->getType())); if (!IdxExpr->isIntegerConstantExpr(Idx, Context)) { Diag(rawAttr->getLoc(), diag::err_attribute_argument_n_not_int, "format", std::string("2"), IdxExpr->getSourceRange()); return; } if (Idx.getZExtValue() < FirstIdx || Idx.getZExtValue() > NumArgs) { Diag(rawAttr->getLoc(), diag::err_attribute_argument_out_of_bounds, "format", std::string("2"), IdxExpr->getSourceRange()); return; } // FIXME: Do we need to bounds check? unsigned ArgIdx = Idx.getZExtValue() - 1; // make sure the format string is really a string QualType Ty = proto->getArgType(ArgIdx); if (is_NSString) { // FIXME: do we need to check if the type is NSString*? What are // the semantics? if (!isNSStringType(Ty, Context)) { // FIXME: Should highlight the actual expression that has the // wrong type. Diag(rawAttr->getLoc(), diag::err_format_attribute_not_NSString, IdxExpr->getSourceRange()); return; } } else if (!Ty->isPointerType() || !Ty->getAsPointerType()->getPointeeType()->isCharType()) { // FIXME: Should highlight the actual expression that has the // wrong type. Diag(rawAttr->getLoc(), diag::err_format_attribute_not_string, IdxExpr->getSourceRange()); return; } // check the 3rd argument Expr *FirstArgExpr = static_cast(rawAttr->getArg(1)); llvm::APSInt FirstArg(Context.getTypeSize(FirstArgExpr->getType())); if (!FirstArgExpr->isIntegerConstantExpr(FirstArg, Context)) { Diag(rawAttr->getLoc(), diag::err_attribute_argument_n_not_int, "format", std::string("3"), FirstArgExpr->getSourceRange()); return; } // check if the function is variadic if the 3rd argument non-zero if (FirstArg != 0) { if (proto->isVariadic()) { ++NumArgs; // +1 for ... } else { Diag(d->getLocation(), diag::err_format_attribute_requires_variadic); return; } } // strftime requires FirstArg to be 0 because it doesn't read from any variable // the input is just the current time + the format string if (is_strftime) { if (FirstArg != 0) { Diag(rawAttr->getLoc(), diag::err_format_strftime_third_parameter, FirstArgExpr->getSourceRange()); return; } // if 0 it disables parameter checking (to use with e.g. va_list) } else if (FirstArg != 0 && FirstArg != NumArgs) { Diag(rawAttr->getLoc(), diag::err_attribute_argument_out_of_bounds, "format", std::string("3"), FirstArgExpr->getSourceRange()); return; } d->addAttr(new FormatAttr(std::string(Format, FormatLen), Idx.getZExtValue(), FirstArg.getZExtValue())); } void Sema::HandleTransparentUnionAttribute(Decl *d, AttributeList *rawAttr) { // check the attribute arguments. if (rawAttr->getNumArgs() != 0) { Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, std::string("0")); return; } TypeDecl *decl = dyn_cast(d); if (!decl || !Context.getTypeDeclType(decl)->isUnionType()) { Diag(rawAttr->getLoc(), diag::warn_attribute_wrong_decl_type, "transparent_union", "union"); return; } //QualType QTy = Context.getTypeDeclType(decl); //const RecordType *Ty = QTy->getAsUnionType(); // FIXME // Ty->addAttr(new TransparentUnionAttr()); } void Sema::HandleAnnotateAttribute(Decl *d, AttributeList *rawAttr) { // check the attribute arguments. if (rawAttr->getNumArgs() != 1) { Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, std::string("1")); return; } Expr *argExpr = static_cast(rawAttr->getArg(0)); StringLiteral *SE = dyn_cast(argExpr); // Make sure that there is a string literal as the annotation's single // argument. if (!SE) { Diag(rawAttr->getLoc(), diag::err_attribute_annotate_no_string); return; } d->addAttr(new AnnotateAttr(std::string(SE->getStrData(), SE->getByteLength()))); } void Sema::HandleAlignedAttribute(Decl *d, AttributeList *rawAttr) { // check the attribute arguments. if (rawAttr->getNumArgs() > 1) { Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, std::string("1")); return; } unsigned Align = 0; if (rawAttr->getNumArgs() == 0) { // FIXME: This should be the target specific maximum alignment. // (For now we just use 128 bits which is the maximum on X86. Align = 128; return; } else { Expr *alignmentExpr = static_cast(rawAttr->getArg(0)); llvm::APSInt alignment(32); if (!alignmentExpr->isIntegerConstantExpr(alignment, Context)) { Diag(rawAttr->getLoc(), diag::err_attribute_argument_not_int, "aligned", alignmentExpr->getSourceRange()); return; } Align = alignment.getZExtValue() * 8; } d->addAttr(new AlignedAttr(Align)); }