Clean up handling of function redeclarations
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@50021 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index eec8ce5..415908a 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -256,8 +256,10 @@
/// 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.
-///
-FunctionDecl *Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) {
+/// 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<FunctionDecl>(OldD);
if (!Old) {
@@ -267,28 +269,31 @@
return New;
}
- MergeAttributes(New, Old);
-
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)
+ 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->getBody())
+ if (Old->isThisDeclarationADefinition())
PrevDiag = diag::err_previous_definition;
else if (Old->isImplicit())
PrevDiag = diag::err_previous_implicit_declaration;
@@ -848,8 +853,18 @@
// 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);
+ bool Redeclaration = false;
+ NewFD = MergeFunctionDecl(NewFD, PrevDecl, Redeclaration);
if (NewFD == 0) return 0;
+ if (Redeclaration) {
+ // Note that the new declaration is a redeclaration of the
+ // older declaration. Then return the older declaration: the
+ // new one is only kept within the set of previous
+ // declarations for this function.
+ FunctionDecl *OldFD = (FunctionDecl *)PrevDecl;
+ OldFD->AddRedeclaration(NewFD);
+ return OldFD;
+ }
}
New = NewFD;
@@ -1177,10 +1192,11 @@
Decl *PrevDcl = LookupDecl(D.getIdentifier(), Decl::IDNS_Ordinary,
GlobalScope);
if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(PrevDcl)) {
- if (FD->getBody()) {
+ const FunctionDecl *Definition;
+ if (FD->getBody(Definition)) {
Diag(D.getIdentifierLoc(), diag::err_redefinition,
D.getIdentifier()->getName());
- Diag(FD->getLocation(), diag::err_previous_definition);
+ Diag(Definition->getLocation(), diag::err_previous_definition);
}
}
Decl *decl = static_cast<Decl*>(ActOnDeclarator(GlobalScope, D, 0));