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gerrit-public.fairphone.software / platform / external / clang / 9de04c4415bd31c0c0e888e9ad5673f6c972e12e / . / Sema / SemaDecl.cpp
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//===--- 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/ASTContext.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 "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) const {
Decl *IIDecl = II.getFETokenInfo<Decl>();
// Find first occurance of none-tagged declaration
while(IIDecl && IIDecl->getIdentifierNamespace() != Decl::IDNS_Ordinary)
IIDecl = cast<ScopedDecl>(IIDecl)->getNext();
if (!IIDecl)
return 0;
if (isa<TypedefDecl>(IIDecl) || isa<ObjCInterfaceDecl>(IIDecl))
return IIDecl;
if (ObjCCompatibleAliasDecl *ADecl =
dyn_cast<ObjCCompatibleAliasDecl>(IIDecl))
return ADecl->getClassInterface();
return 0;
}
void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) {
if (S->decl_empty()) return;
assert((S->getFlags() & Scope::DeclScope) &&"Scope shouldn't contain decls!");
for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end();
I != E; ++I) {
Decl *TmpD = static_cast<Decl*>(*I);
assert(TmpD && "This decl didn't get pushed??");
ScopedDecl *D = dyn_cast<ScopedDecl>(TmpD);
assert(D && "This decl isn't a ScopedDecl?");
IdentifierInfo *II = D->getIdentifier();
if (!II) continue;
// Unlink this decl from the identifier. Because the scope contains decls
// in an unordered collection, and because we have multiple identifier
// namespaces (e.g. tag, normal, label),the decl may not be the first entry.
if (II->getFETokenInfo<Decl>() == D) {
// Normal case, no multiple decls in different namespaces.
II->setFETokenInfo(D->getNext());
} else {
// Scan ahead. There are only three namespaces in C, so this loop can
// never execute more than 3 times.
ScopedDecl *SomeDecl = II->getFETokenInfo<ScopedDecl>();
while (SomeDecl->getNext() != D) {
SomeDecl = SomeDecl->getNext();
assert(SomeDecl && "Didn't find this decl on its identifier's chain!");
}
SomeDecl->setNext(D->getNext());
}
// 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);
}
}
/// LookupInterfaceDecl - Lookup interface declaration in the scope chain.
/// Return the first declaration found (which may or may not be a class
/// declaration. Caller is responsible for handling the none-class case.
/// Bypassing the alias of a class by returning the aliased class.
ScopedDecl *Sema::LookupInterfaceDecl(IdentifierInfo *ClassName) {
ScopedDecl *IDecl;
// Scan up the scope chain looking for a decl that matches this identifier
// that is in the appropriate namespace.
for (IDecl = ClassName->getFETokenInfo<ScopedDecl>(); IDecl;
IDecl = IDecl->getNext())
if (IDecl->getIdentifierNamespace() == Decl::IDNS_Ordinary)
break;
if (ObjCCompatibleAliasDecl *ADecl =
dyn_cast_or_null<ObjCCompatibleAliasDecl>(IDecl))
return ADecl->getClassInterface();
return IDecl;
}
/// getObjCInterfaceDecl - Look up a for a class declaration in the scope.
/// return 0 if one not found.
ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) {
ScopedDecl *IdDecl = LookupInterfaceDecl(Id);
return cast_or_null<ObjCInterfaceDecl>(IdDecl);
}
/// LookupScopedDecl - Look up the inner-most declaration in the specified
/// namespace.
ScopedDecl *Sema::LookupScopedDecl(IdentifierInfo *II, unsigned NSI,
SourceLocation IdLoc, Scope *S) {
if (II == 0) return 0;
Decl::IdentifierNamespace NS = (Decl::IdentifierNamespace)NSI;
// 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 (ScopedDecl *D = II->getFETokenInfo<ScopedDecl>(); D; D = D->getNext())
if (D->getIdentifierNamespace() == NS)
return D;
// 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 this is a builtin on some other target, or if this builtin varies
// across targets (e.g. in type), emit a diagnostic and mark the translation
// unit non-portable for using it.
if (II->isNonPortableBuiltin()) {
// Only emit this diagnostic once for this builtin.
II->setNonPortableBuiltin(false);
Context.Target.DiagnoseNonPortability(Context.getFullLoc(IdLoc),
diag::port_target_builtin_use);
}
// If this is a builtin on this (or all) targets, create the decl.
if (unsigned BuiltinID = II->getBuiltinID())
return LazilyCreateBuiltin(II, BuiltinID, S);
}
return 0;
}
void Sema::InitBuiltinVaListType()
{
if (!Context.getBuiltinVaListType().isNull())
return;
IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list");
ScopedDecl *VaDecl = LookupScopedDecl(VaIdent, Decl::IDNS_Ordinary,
SourceLocation(), TUScope);
TypedefDecl *VaTypedef = cast<TypedefDecl>(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 = new FunctionDecl(SourceLocation(), II, R,
FunctionDecl::Extern, false, 0);
// Find translation-unit scope to insert this function into.
if (Scope *FnS = S->getFnParent())
S = FnS->getParent(); // Skip all scopes in a function at once.
while (S->getParent())
S = S->getParent();
S->AddDecl(New);
// Add this decl to the end of the identifier info.
if (ScopedDecl *LastDecl = II->getFETokenInfo<ScopedDecl>()) {
// Scan until we find the last (outermost) decl in the id chain.
while (LastDecl->getNext())
LastDecl = LastDecl->getNext();
// Insert before (outside) it.
LastDecl->setNext(New);
} else {
II->setFETokenInfo(New);
}
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, ScopedDecl *OldD) {
// Verify the old decl was also a typedef.
TypedefDecl *Old = dyn_cast<TypedefDecl>(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;
// 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;
}
/// MergeFunctionDecl - We just parsed a function '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.
///
FunctionDecl *Sema::MergeFunctionDecl(FunctionDecl *New, ScopedDecl *OldD) {
// Verify the old decl was also a function.
FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD);
if (!Old) {
Diag(New->getLocation(), diag::err_redefinition_different_kind,
New->getName());
Diag(OldD->getLocation(), diag::err_previous_definition);
return New;
}
QualType OldQType = Old->getCanonicalType();
QualType NewQType = New->getCanonicalType();
// This is not right, but it's a start.
// If Old is a function prototype with no defined arguments we only compare
// the return type; If arguments are defined on the prototype we validate the
// entire function type.
// FIXME: We should link up decl objects here.
if (Old->getBody() == 0) {
if (OldQType.getTypePtr()->getTypeClass() == Type::FunctionNoProto &&
Old->getResultType() == New->getResultType())
return New;
}
// Function types need to be compatible, not identical. This handles
// duplicate function decls like "void f(int); void f(enum X);" properly.
if (Context.functionTypesAreCompatible(OldQType, NewQType))
return New;
// A function that has already been declared has been redeclared or defined
// with a different type- show appropriate diagnostic
diag::kind PrevDiag = Old->getBody() ? diag::err_previous_definition :
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;
}
/// hasUndefinedLength - Used by equivalentArrayTypes to determine whether the
/// the outermost VariableArrayType has no size defined.
static bool hasUndefinedLength(const ArrayType *Array) {
const VariableArrayType *VAT = Array->getAsVariableArrayType();
return VAT && !VAT->getSizeExpr();
}
/// 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 (hasUndefinedLength(NewAT) || hasUndefinedLength(OldAT)) {
if (NewAT->getIndexTypeQualifier() != OldAT->getIndexTypeQualifier())
return false;
NewQType = NewAT->getElementType();
OldQType = OldAT->getElementType();
}
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, ScopedDecl *OldD) {
// Verify the old decl was also a variable.
VarDecl *Old = dyn_cast<VarDecl>(OldD);
if (!Old) {
Diag(New->getLocation(), diag::err_redefinition_different_kind,
New->getName());
Diag(OldD->getLocation(), diag::err_previous_definition);
return New;
}
FileVarDecl *OldFSDecl = dyn_cast<FileVarDecl>(Old);
FileVarDecl *NewFSDecl = dyn_cast<FileVarDecl>(New);
bool OldIsTentative = false;
if (OldFSDecl && NewFSDecl) { // C99 6.9.2
// Handle C "tentative" external object definitions. FIXME: finish!
if (!OldFSDecl->getInit() &&
(OldFSDecl->getStorageClass() == VarDecl::None ||
OldFSDecl->getStorageClass() == VarDecl::Static))
OldIsTentative = true;
}
// Verify the types match.
if (Old->getCanonicalType() != New->getCanonicalType() &&
!areEquivalentArrayTypes(New->getCanonicalType(), Old->getCanonicalType())) {
Diag(New->getLocation(), diag::err_redefinition, New->getName());
Diag(Old->getLocation(), diag::err_previous_definition);
return New;
}
// We've verified the types match, now check if Old is "extern".
if (Old->getStorageClass() != VarDecl::Extern) {
Diag(New->getLocation(), diag::err_redefinition, New->getName());
Diag(Old->getLocation(), diag::err_previous_definition);
}
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<TagDecl>(static_cast<Decl *>(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;
}
void Sema::CheckVariableInitList(QualType DeclType, InitListExpr *IList,
QualType ElementType,
int &nInitializers, bool &hadError) {
unsigned numInits = IList->getNumInits();
if (numInits) {
if (CheckForCharArrayInitializer(IList, ElementType, nInitializers,
false, hadError))
return;
for (unsigned i = 0; i < numInits; i++) {
Expr *expr = IList->getInit(i);
if (InitListExpr *InitList = dyn_cast<InitListExpr>(expr)) {
if (const ConstantArrayType *CAT = DeclType->getAsConstantArrayType()) {
int maxElements = CAT->getMaximumElements();
CheckConstantInitList(DeclType, InitList, ElementType,
maxElements, hadError);
}
} else {
hadError = CheckInitExpr(expr, IList, i, ElementType);
}
nInitializers++;
}
} else {
Diag(IList->getLocStart(),
diag::err_at_least_one_initializer_needed_to_size_array);
hadError = true;
}
}
bool Sema::CheckForCharArrayInitializer(InitListExpr *IList,
QualType ElementType,
int &nInitializers, bool isConstant,
bool &hadError)
{
if (ElementType->isPointerType())
return false;
if (StringLiteral *literal = dyn_cast<StringLiteral>(IList->getInit(0))) {
// FIXME: Handle wide strings
if (ElementType->isCharType()) {
if (isConstant) {
if (literal->getByteLength() > (unsigned)nInitializers) {
Diag(literal->getSourceRange().getBegin(),
diag::warn_initializer_string_for_char_array_too_long,
literal->getSourceRange());
}
} else {
nInitializers = literal->getByteLength() + 1;
}
} else {
// FIXME: It might be better if we could point to the declaration
// here, instead of the string literal.
Diag(literal->getSourceRange().getBegin(),
diag::array_of_wrong_type_initialized_from_string,
ElementType.getAsString());
hadError = true;
}
// Check for excess initializers
for (unsigned i = 1; i < IList->getNumInits(); i++) {
Expr *expr = IList->getInit(i);
Diag(expr->getLocStart(),
diag::err_excess_initializers_in_char_array_initializer,
expr->getSourceRange());
}
return true;
}
return false;
}
// FIXME: Doesn't deal with arrays of structures yet.
void Sema::CheckConstantInitList(QualType DeclType, InitListExpr *IList,
QualType ElementType,
int &totalInits, bool &hadError) {
int maxElementsAtThisLevel = 0;
int nInitsAtLevel = 0;
if (ElementType->isRecordType()) // FIXME: until we support structures...
return;
if (const ConstantArrayType *CAT = DeclType->getAsConstantArrayType()) {
// We have a constant array type, compute maxElements *at this level*.
maxElementsAtThisLevel = CAT->getMaximumElements();
// Set DeclType, used below to recurse (for multi-dimensional arrays).
DeclType = CAT->getElementType();
} else if (DeclType->isScalarType()) {
if (const VectorType *VT = DeclType->getAsVectorType())
maxElementsAtThisLevel = VT->getNumElements();
else {
Diag(IList->getLocStart(), diag::warn_braces_around_scalar_init,
IList->getSourceRange());
maxElementsAtThisLevel = 1;
}
}
// The empty init list "{ }" is treated specially below.
unsigned numInits = IList->getNumInits();
if (numInits) {
if (CheckForCharArrayInitializer(IList, ElementType,
maxElementsAtThisLevel,
true, hadError))
return;
for (unsigned i = 0; i < numInits; i++) {
Expr *expr = IList->getInit(i);
if (InitListExpr *InitList = dyn_cast<InitListExpr>(expr)) {
CheckConstantInitList(DeclType, InitList, ElementType,
totalInits, hadError);
} else {
hadError = CheckInitExpr(expr, IList, i, ElementType);
nInitsAtLevel++; // increment the number of initializers at this level.
totalInits--; // decrement the total number of initializers.
// Check if we have space for another initializer.
if (((nInitsAtLevel > maxElementsAtThisLevel) || (totalInits < 0)))
Diag(expr->getLocStart(), diag::warn_excess_initializers,
expr->getSourceRange());
}
}
if (nInitsAtLevel < maxElementsAtThisLevel) // fill the remaining elements.
totalInits -= (maxElementsAtThisLevel - nInitsAtLevel);
} else {
// we have an initializer list with no elements.
totalInits -= maxElementsAtThisLevel;
if (totalInits < 0)
Diag(IList->getLocStart(), diag::warn_excess_initializers,
IList->getSourceRange());
}
}
bool Sema::CheckStringLiteralInit(StringLiteral *strLiteral, QualType &DeclT) {
if (const VariableArrayType *VAT = 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(VAT->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) {
StringLiteral *strLiteral = dyn_cast<StringLiteral>(Init);
const ArrayType *AT = DeclType->getAsArrayType();
if (strLiteral && (AT && AT->getElementType()->isCharType()))
return strLiteral;
return 0;
}
bool Sema::CheckInitializerTypes(Expr *&Init, QualType &DeclType) {
bool hadError = false;
// 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->getAsVariablyModifiedType())
return Diag(VAT->getSizeExpr()->getLocStart(),
diag::err_variable_object_no_init,
VAT->getSizeExpr()->getSourceRange());
InitListExpr *InitList = dyn_cast<InitListExpr>(Init);
if (!InitList) {
// FIXME: Handle wide strings
if (StringLiteral *strLiteral = IsStringLiteralInit(Init, DeclType))
return CheckStringLiteralInit(strLiteral, DeclType);
return CheckSingleInitializer(Init, DeclType);
}
// We have an InitListExpr, make sure we set the type.
Init->setType(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->getAsIncompleteArrayType()) {
// We have a VariableArrayType with unknown size. Note that only the first
// array can have unknown size. For example, "int [][]" is illegal.
int numInits = 0;
CheckVariableInitList(VAT->getElementType(), InitList, VAT->getBaseType(),
numInits, hadError);
llvm::APSInt ConstVal(32);
if (!hadError)
ConstVal = numInits;
// Return a new array type from the number of initializers (C99 6.7.8p22).
// Note that if there was an error, we will still set the decl type,
// to an array type with 0 elements.
// This is to avoid "incomplete type foo[]" errors when we've already
// reported the real cause of the error.
DeclType = Context.getConstantArrayType(VAT->getElementType(), ConstVal,
ArrayType::Normal, 0);
return hadError;
}
if (const ConstantArrayType *CAT = DeclType->getAsConstantArrayType()) {
int maxElements = CAT->getMaximumElements();
CheckConstantInitList(DeclType, InitList, CAT->getBaseType(),
maxElements, hadError);
return hadError;
}
if (const VectorType *VT = DeclType->getAsVectorType()) {
int maxElements = VT->getNumElements();
CheckConstantInitList(DeclType, InitList, VT->getElementType(),
maxElements, hadError);
return hadError;
}
if (DeclType->isScalarType()) { // C99 6.7.8p11: Allow "int x = { 1, 2 };"
int maxElements = 1;
CheckConstantInitList(DeclType, InitList, DeclType, maxElements, hadError);
return hadError;
}
// FIXME: Handle struct/union types, including those appearing in a
// CompoundLiteralExpr...
return hadError;
}
Sema::DeclTy *
Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl) {
ScopedDecl *LastDeclarator = dyn_cast_or_null<ScopedDecl>((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.
ScopedDecl *PrevDecl = LookupScopedDecl(II, Decl::IDNS_Ordinary,
D.getIdentifierLoc(), S);
ScopedDecl *New;
bool InvalidDecl = false;
QualType R = GetTypeForDeclarator(D, S);
assert(!R.isNull() && "GetTypeForDeclarator() returned null type");
if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) {
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 && S->isDeclScope(PrevDecl)) {
NewTD = MergeTypeDefDecl(NewTD, PrevDecl);
if (NewTD == 0) return 0;
}
New = NewTD;
if (S->getParent() == 0) {
// C99 6.7.7p2: If a typedef name specifies a variably modified type
// then it shall have block scope.
if (const VariableArrayType *VAT =
NewTD->getUnderlyingType()->getAsVariablyModifiedType()) {
Diag(D.getIdentifierLoc(), diag::err_typecheck_illegal_vla,
VAT->getSizeExpr()->getSourceRange());
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;
}
FunctionDecl *NewFD = new FunctionDecl(D.getIdentifierLoc(), II, R, SC,
D.getDeclSpec().isInlineSpecified(),
LastDeclarator,
D.getDeclSpec().getAttributes());
// Transfer ownership of DeclSpec attributes to FunctionDecl
D.getDeclSpec().clearAttributes();
// 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) {
NewFD = MergeFunctionDecl(NewFD, PrevDecl);
if (NewFD == 0) return 0;
}
New = NewFD;
} else {
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;
}
if (S->getParent() == 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 = new FileVarDecl(D.getIdentifierLoc(), II, R, SC, LastDeclarator);
} else {
NewVD = new BlockVarDecl(D.getIdentifierLoc(), II, R, SC, LastDeclarator);
}
// Handle attributes prior to checking for duplicates in MergeVarDecl
HandleDeclAttributes(NewVD, 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 && S->isDeclScope(PrevDecl)) {
NewVD = MergeVarDecl(NewVD, PrevDecl);
if (NewVD == 0) return 0;
}
New = NewVD;
}
// If this has an identifier, add it to the scope stack.
if (II) {
New->setNext(II->getFETokenInfo<ScopedDecl>());
II->setFETokenInfo(New);
S->AddDecl(New);
}
// If any semantic error occurred, mark the decl as invalid.
if (D.getInvalidType() || InvalidDecl)
New->setInvalidDecl();
return New;
}
bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) {
SourceLocation loc;
// FIXME: Remove the isReference check and handle assignment to a reference.
if (!DclT->isReferenceType() && !Init->isConstantExpr(Context, &loc)) {
assert(loc.isValid() && "isConstantExpr didn't return a loc!");
Diag(loc, diag::err_init_element_not_constant, Init->getSourceRange());
return true;
}
return false;
}
void Sema::AddInitializerToDecl(DeclTy *dcl, ExprTy *init) {
Decl *RealDecl = static_cast<Decl *>(dcl);
Expr *Init = static_cast<Expr *>(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<VarDecl>(RealDecl);
if (!VDecl) {
Diag(dyn_cast<ScopedDecl>(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 (BlockVarDecl *BVD = dyn_cast<BlockVarDecl>(VDecl)) {
VarDecl::StorageClass SC = BVD->getStorageClass();
if (SC == VarDecl::Extern) { // C99 6.7.8p5
Diag(VDecl->getLocation(), diag::err_block_extern_cant_init);
BVD->setInvalidDecl();
} else if (!BVD->isInvalidDecl()) {
CheckInitializerTypes(Init, DclT);
if (SC == VarDecl::Static) // C99 6.7.8p4.
CheckForConstantInitializer(Init, DclT);
}
} else if (FileVarDecl *FVD = dyn_cast<FileVarDecl>(VDecl)) {
if (FVD->getStorageClass() == VarDecl::Extern)
Diag(VDecl->getLocation(), diag::warn_extern_init);
if (!FVD->isInvalidDecl())
CheckInitializerTypes(Init, DclT);
// 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<Decl*>(group);
if (GroupDecl == 0)
return 0;
ScopedDecl *Group = dyn_cast<ScopedDecl>(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<VarDecl>(ID);
if (!IDecl)
continue;
FileVarDecl *FVD = dyn_cast<FileVarDecl>(IDecl);
BlockVarDecl *BVD = dyn_cast<BlockVarDecl>(IDecl);
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 ((FVD || BVD) && IDecl->getStorageClass() == VarDecl::Static) {
if (const VariableArrayType *VLA = T->getAsVariableArrayType()) {
if (VLA->getSizeExpr()) {
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 (BVD && IDecl->getStorageClass() != VarDecl::Extern) {
if (T->isIncompleteType()) {
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 (FVD && !FVD->getInit() && (FVD->getStorageClass() == VarDecl::Static ||
FVD->getStorageClass() == VarDecl::None)) {
const VariableArrayType *VAT = T->getAsVariableArrayType();
if (VAT && VAT->getSizeExpr() == 0) {
// C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete
// array to be completed. Don't issue a diagnostic.
} else if (T->isIncompleteType()) {
// 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;
}
// Called from Sema::ParseStartOfFunctionDef().
ParmVarDecl *
Sema::ActOnParamDeclarator(struct DeclaratorChunk::ParamInfo &PI, Scope *FnScope)
{
IdentifierInfo *II = PI.Ident;
// 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.
if (/*Decl *PrevDecl = */LookupScopedDecl(II, Decl::IDNS_Ordinary,
PI.IdentLoc, FnScope)) {
}
// FIXME: Handle storage class (auto, register). No declarator?
// TODO: Chain to previous parameter with the prevdeclarator chain?
// 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)...
//
QualType parmDeclType = QualType::getFromOpaquePtr(PI.TypeInfo);
if (const ArrayType *AT = parmDeclType->getAsArrayType()) {
// int x[restrict 4] -> int *restrict
parmDeclType = Context.getPointerType(AT->getElementType());
parmDeclType = parmDeclType.getQualifiedType(AT->getIndexTypeQualifier());
} else if (parmDeclType->isFunctionType())
parmDeclType = Context.getPointerType(parmDeclType);
ParmVarDecl *New = new ParmVarDecl(PI.IdentLoc, II, parmDeclType,
VarDecl::None, 0, PI.AttrList);
if (PI.InvalidType)
New->setInvalidDecl();
// If this has an identifier, add it to the scope stack.
if (II) {
New->setNext(II->getFETokenInfo<ScopedDecl>());
II->setFETokenInfo(New);
FnScope->AddDecl(New);
}
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].TypeInfo == 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.
FTI.ArgInfo[i].TypeInfo = Context.IntTy.getAsOpaquePtr();
}
}
// Since this is a function definition, act as though we have information
// about the arguments.
FTI.hasPrototype = true;
} else {
// FIXME: Diagnose arguments without names in C.
}
Scope *GlobalScope = FnBodyScope->getParent();
// See if this is a redefinition.
ScopedDecl *PrevDcl = LookupScopedDecl(D.getIdentifier(), Decl::IDNS_Ordinary,
D.getIdentifierLoc(), GlobalScope);
if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(PrevDcl)) {
if (FD->getBody()) {
Diag(D.getIdentifierLoc(), diag::err_redefinition,
D.getIdentifier()->getName());
Diag(FD->getLocation(), diag::err_previous_definition);
}
}
FunctionDecl *FD =
static_cast<FunctionDecl*>(ActOnDeclarator(GlobalScope, D, 0));
assert(FD != 0 && "ActOnDeclarator() didn't return a FunctionDecl");
CurFunctionDecl = FD;
// Create Decl objects for each parameter, adding them to the FunctionDecl.
llvm::SmallVector<ParmVarDecl*, 16> 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.
if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 &&
!QualType::getFromOpaquePtr(FTI.ArgInfo[0].TypeInfo).getQualifiers() &&
QualType::getFromOpaquePtr(FTI.ArgInfo[0].TypeInfo)->isVoidType()) {
// empty arg list, don't push any params.
} else {
for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) {
Params.push_back(ActOnParamDeclarator(D.getTypeObject(0).Fun.ArgInfo[i],
FnBodyScope));
}
}
FD->setParams(&Params[0], Params.size());
return FD;
}
Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtTy *Body) {
Decl *dcl = static_cast<Decl *>(D);
if (FunctionDecl *FD = dyn_cast<FunctionDecl>(dcl)) {
FD->setBody((Stmt*)Body);
assert(FD == CurFunctionDecl && "Function parsing confused");
CurFunctionDecl = 0;
} else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(dcl)) {
MD->setBody((Stmt*)Body);
CurMethodDecl = 0;
}
// Verify and clean out per-function state.
// Check goto/label use.
for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::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.
L->setSubStmt(new NullStmt(L->getIdentLoc()));
cast<CompoundStmt>((Stmt*)Body)->push_back(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) {
if (getLangOptions().C99) // Extension in C99.
Diag(Loc, diag::ext_implicit_function_decl, II.getName());
else // Legal in C90, but warn about it.
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);
// Find translation-unit scope to insert this function into.
if (Scope *FnS = S->getFnParent())
S = FnS->getParent(); // Skip all scopes in a function at once.
while (S->getParent())
S = S->getParent();
return dyn_cast<ScopedDecl>(static_cast<Decl*>(ActOnDeclarator(S, D, 0)));
}
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 = new TypedefDecl(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.
if (TagDecl *PrevDecl =
dyn_cast_or_null<TagDecl>(LookupScopedDecl(Name, Decl::IDNS_Tag,
NameLoc, S))) {
// 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 || S->isDeclScope(PrevDecl)) {
// 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 (PrevDecl->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.
}
// 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 = new EnumDecl(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 = new RecordDecl(Kind, 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.
New->setNext(Name->getFETokenInfo<ScopedDecl>());
Name->setFETokenInfo(New);
S->AddDecl(New);
}
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, DeclTy *TagDecl,
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 (const VariableArrayType *VAT = T->getAsVariablyModifiedType()) {
Diag(Loc, diag::err_typecheck_illegal_vla,
VAT->getSizeExpr()->getSourceRange());
InvalidDecl = true;
}
// FIXME: Chain fielddecls together.
FieldDecl *NewFD;
if (isa<RecordDecl>(static_cast<Decl *>(TagDecl)))
NewFD = new FieldDecl(Loc, II, T, BitWidth);
else if (isa<ObjCInterfaceDecl>(static_cast<Decl *>(TagDecl)) ||
isa<ObjCImplementationDecl>(static_cast<Decl *>(TagDecl)) ||
isa<ObjCCategoryDecl>(static_cast<Decl *>(TagDecl)) ||
// FIXME: ivars are currently used to model properties, and
// properties can appear within a protocol.
// See corresponding FIXME in DeclObjC.h:ObjCPropertyDecl.
isa<ObjCProtocolDecl>(static_cast<Decl *>(TagDecl)))
NewFD = new ObjCIvarDecl(Loc, II, T);
else
assert(0 && "Sema::ActOnField(): Unknown TagDecl");
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");
}
}
void Sema::ActOnFields(Scope* S,
SourceLocation RecLoc, DeclTy *RecDecl,
DeclTy **Fields, unsigned NumFields,
SourceLocation LBrac, SourceLocation RBrac,
tok::ObjCKeywordKind *visibility) {
Decl *EnclosingDecl = static_cast<Decl*>(RecDecl);
assert(EnclosingDecl && "missing record or interface decl");
RecordDecl *Record = dyn_cast<RecordDecl>(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<FieldDecl*, 32> RecFields;
llvm::SmallSet<const IdentifierInfo*, 32> FieldIDs;
for (unsigned i = 0; i != NumFields; ++i) {
FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(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();
// If we have visibility info, make sure the AST is set accordingly.
if (visibility)
cast<ObjCIvarDecl>(FD)->setAccessControl(
TranslateIvarVisibility(visibility[i]));
// 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());
else {
ObjCIvarDecl **ClsFields =
reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]);
if (isa<ObjCInterfaceDecl>(static_cast<Decl*>(RecDecl)))
cast<ObjCInterfaceDecl>(static_cast<Decl*>(RecDecl))->
addInstanceVariablesToClass(ClsFields, RecFields.size(), RBrac);
else if (isa<ObjCImplementationDecl>(static_cast<Decl*>(RecDecl))) {
ObjCImplementationDecl* IMPDecl =
cast<ObjCImplementationDecl>(static_cast<Decl*>(RecDecl));
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) {
theEnumDecl = theEnumDecl; // silence unused warning.
EnumConstantDecl *LastEnumConst =
cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst));
Expr *Val = static_cast<Expr*>(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 (ScopedDecl *PrevDecl = LookupScopedDecl(Id, Decl::IDNS_Ordinary,
IdLoc, S)) {
if (S->isDeclScope(PrevDecl)) {
if (isa<EnumConstantDecl>(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);
// FIXME: Don't leak memory: 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());
// FIXME: Don't leak memory: 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<uint32_t>(Context.getTypeSize(EltTy, IdLoc)));
}
}
EnumConstantDecl *New = new EnumConstantDecl(IdLoc, Id, EltTy, Val, EnumVal,
LastEnumConst);
// Register this decl in the current scope stack.
New->setNext(Id->getFETokenInfo<ScopedDecl>());
Id->setFETokenInfo(New);
S->AddDecl(New);
return New;
}
void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX,
DeclTy **Elements, unsigned NumElements) {
EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(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(Context.getFullLoc(Enum->getLocation()));
// 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<EnumConstantDecl>(static_cast<Decl*>(Elements[i]));
if (!ECD) continue; // Already issued a diagnostic.
// If the enum value doesn't fit in an int, emit an extension warning.
assert(ECD->getInitVal().getBitWidth() >= IntWidth &&
"Should have promoted value to int");
const llvm::APSInt &InitVal = ECD->getInitVal();
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.isNegative())
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(Context.getFullLoc(Enum->getLocation()));
if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth)
BestType = Context.LongTy;
else {
BestWidth = Context.Target.getLongLongWidth(
Context.getFullLoc(Enum->getLocation()));
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(
Context.getFullLoc(Enum->getLocation()))))
BestType = Context.UnsignedLongTy;
else {
BestWidth =
Context.Target.getLongLongWidth(Context.getFullLoc(Enum->getLocation()));
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<EnumConstantDecl>(static_cast<Decl*>(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)
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);
}
Sema::DeclTy* Sema::ActOnLinkageSpec(SourceLocation Loc,
SourceLocation LBrace,
SourceLocation RBrace,
const char *Lang,
unsigned StrSize,
DeclTy *D) {
LinkageSpecDecl::LanguageIDs Language;
Decl *dcl = static_cast<Decl *>(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 new LinkageSpecDecl(Loc, Language, dcl);
}
void Sema::HandleDeclAttribute(Decl *New, AttributeList *rawAttr) {
const char *attrName = rawAttr->getAttributeName()->getName();
unsigned attrLen = rawAttr->getAttributeName()->getLength();
// Normalize the attribute name, __foo__ becomes foo.
if (attrLen > 4 && attrName[0] == '_' && attrName[1] == '_' &&
attrName[attrLen - 2] == '_' && attrName[attrLen - 1] == '_') {
attrName += 2;
attrLen -= 4;
}
if (attrLen == 11 && !memcmp(attrName, "vector_size", 11)) {
if (ValueDecl *vDecl = dyn_cast<ValueDecl>(New)) {
QualType newType = HandleVectorTypeAttribute(vDecl->getType(), rawAttr);
if (!newType.isNull()) // install the new vector type into the decl
vDecl->setType(newType);
}
if (TypedefDecl *tDecl = dyn_cast<TypedefDecl>(New)) {
QualType newType = HandleVectorTypeAttribute(tDecl->getUnderlyingType(),
rawAttr);
if (!newType.isNull()) // install the new vector type into the decl
tDecl->setUnderlyingType(newType);
}
} else if (attrLen == 15 && !memcmp(attrName, "ocu_vector_type", 15)) {
if (TypedefDecl *tDecl = dyn_cast<TypedefDecl>(New))
HandleOCUVectorTypeAttribute(tDecl, rawAttr);
else
Diag(rawAttr->getAttributeLoc(),
diag::err_typecheck_ocu_vector_not_typedef);
} else if (attrLen == 7 && !memcmp(attrName, "aligned", 7)) {
HandleAlignedAttribute(New, rawAttr);
}
// FIXME: add other attributes...
}
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::HandleOCUVectorTypeAttribute(TypedefDecl *tDecl,
AttributeList *rawAttr) {
QualType curType = tDecl->getUnderlyingType();
// check the attribute arguments.
if (rawAttr->getNumArgs() != 1) {
Diag(rawAttr->getAttributeLoc(), diag::err_attribute_wrong_number_arguments,
std::string("1"));
return;
}
Expr *sizeExpr = static_cast<Expr *>(rawAttr->getArg(0));
llvm::APSInt vecSize(32);
if (!sizeExpr->isIntegerConstantExpr(vecSize, Context)) {
Diag(rawAttr->getAttributeLoc(), diag::err_attribute_vector_size_not_int,
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->getAttributeLoc(), 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<unsigned>(vecSize.getZExtValue());
if (vectorSize == 0) {
Diag(rawAttr->getAttributeLoc(), diag::err_attribute_zero_size,
sizeExpr->getSourceRange());
return;
}
// Instantiate/Install the vector type, the number of elements is > 0.
tDecl->setUnderlyingType(Context.getOCUVectorType(curType, vectorSize));
// Remember this typedef decl, we will need it later for diagnostics.
OCUVectorDecls.push_back(tDecl);
}
QualType Sema::HandleVectorTypeAttribute(QualType curType,
AttributeList *rawAttr) {
// check the attribute arugments.
if (rawAttr->getNumArgs() != 1) {
Diag(rawAttr->getAttributeLoc(), diag::err_attribute_wrong_number_arguments,
std::string("1"));
return QualType();
}
Expr *sizeExpr = static_cast<Expr *>(rawAttr->getArg(0));
llvm::APSInt vecSize(32);
if (!sizeExpr->isIntegerConstantExpr(vecSize, Context)) {
Diag(rawAttr->getAttributeLoc(), diag::err_attribute_vector_size_not_int,
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<PointerType>(canonType))
canonType = PT->getPointeeType().getTypePtr();
else if (ArrayType *AT = dyn_cast<ArrayType>(canonType))
canonType = AT->getElementType().getTypePtr();
else if (FunctionType *FT = dyn_cast<FunctionType>(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->getAttributeLoc(), diag::err_attribute_invalid_vector_type,
curType.getCanonicalType().getAsString());
return QualType();
}
unsigned typeSize = static_cast<unsigned>(
Context.getTypeSize(curType, rawAttr->getAttributeLoc()));
// vecSize is specified in bytes - convert to bits.
unsigned vectorSize = static_cast<unsigned>(vecSize.getZExtValue() * 8);
// the vector size needs to be an integral multiple of the type size.
if (vectorSize % typeSize) {
Diag(rawAttr->getAttributeLoc(), diag::err_attribute_invalid_size,
sizeExpr->getSourceRange());
return QualType();
}
if (vectorSize == 0) {
Diag(rawAttr->getAttributeLoc(), diag::err_attribute_zero_size,
sizeExpr->getSourceRange());
return QualType();
}
// Since OpenCU requires 3 element vectors (OpenCU 5.1.2), we don't restrict
// the number of elements to be a power of two (unlike GCC).
// Instantiate the vector type, the number of elements is > 0.
return Context.getVectorType(curType, vectorSize/typeSize);
}
void Sema::HandleAlignedAttribute(Decl *d, AttributeList *rawAttr)
{
// check the attribute arguments.
// FIXME: Handle the case where are no arguments.
if (rawAttr->getNumArgs() != 1) {
Diag(rawAttr->getAttributeLoc(), diag::err_attribute_wrong_number_arguments,
std::string("1"));
return;
}
Expr *alignmentExpr = static_cast<Expr *>(rawAttr->getArg(0));
llvm::APSInt alignment(32);
if (!alignmentExpr->isIntegerConstantExpr(alignment, Context)) {
Diag(rawAttr->getAttributeLoc(), diag::err_attribute_vector_size_not_int,
alignmentExpr->getSourceRange());
return;
}
}