When synthesizing a label declaration based on a goto statement that
cannot yet be resolved, be sure to push the new label declaration into
the right place within the identifier chain. Otherwise, name lookup in
C++ gets confused when searching for names that are lexically closer
than the label. Fixes PR9463.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@127623 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/clang/Sema/IdentifierResolver.h b/include/clang/Sema/IdentifierResolver.h
index 770f146..33486c2 100644
--- a/include/clang/Sema/IdentifierResolver.h
+++ b/include/clang/Sema/IdentifierResolver.h
@@ -53,6 +53,11 @@
/// declaration was not found, returns false.
bool ReplaceDecl(NamedDecl *Old, NamedDecl *New);
+ /// \brief Insert the given declaration at the given position in the list.
+ void InsertDecl(DeclsTy::iterator Pos, NamedDecl *D) {
+ Decls.insert(Pos, D);
+ }
+
private:
DeclsTy Decls;
};
@@ -166,6 +171,10 @@
/// (and, therefore, replaced).
bool ReplaceDecl(NamedDecl *Old, NamedDecl *New);
+ /// \brief Insert the given declaration prior to the given iterator
+ /// position
+ void InsertDecl(iterator Pos, NamedDecl *D);
+
/// \brief Link the declaration into the chain of declarations for
/// the given identifier.
///
diff --git a/lib/Sema/IdentifierResolver.cpp b/lib/Sema/IdentifierResolver.cpp
index 1085622..fcfc053 100644
--- a/lib/Sema/IdentifierResolver.cpp
+++ b/lib/Sema/IdentifierResolver.cpp
@@ -168,6 +168,39 @@
IDI->AddDecl(D);
}
+void IdentifierResolver::InsertDecl(iterator Pos, NamedDecl *D) {
+ if (Pos == iterator()) {
+ // Simple case: insert at the beginning of the list (which is the
+ // end of the stored vector).
+ AddDecl(D);
+ return;
+ }
+
+ DeclarationName Name = D->getDeclName();
+ void *Ptr = Name.getFETokenInfo<void>();
+
+ if (isDeclPtr(Ptr)) {
+ // There's only one element, and we want to insert before it in the list.
+ // Just create the storage for these identifiers and insert them in the
+ // opposite order we normally would.
+ assert(isDeclPtr(Ptr) && "Not a single declaration!");
+ Name.setFETokenInfo(NULL);
+ IdDeclInfo *IDI = &(*IdDeclInfos)[Name];
+ NamedDecl *PrevD = static_cast<NamedDecl*>(Ptr);
+ IDI->AddDecl(D);
+ IDI->AddDecl(PrevD);
+ return;
+ }
+
+ // General case: insert the declaration at the appropriate point in the
+ // list, which already has at least two elements.
+ IdDeclInfo *IDI = toIdDeclInfo(Ptr);
+ if (Pos.isIterator())
+ IDI->InsertDecl(Pos.getIterator(), D);
+ else
+ IDI->InsertDecl(IDI->decls_begin(), D);
+}
+
/// RemoveDecl - Unlink the decl from its shadowed decl chain.
/// The decl must already be part of the decl chain.
void IdentifierResolver::RemoveDecl(NamedDecl *D) {
diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index 7c3f726..19d96f2 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -494,7 +494,20 @@
}
S->AddDecl(D);
- IdResolver.AddDecl(D);
+
+ if (isa<LabelDecl>(D) && !cast<LabelDecl>(D)->isGnuLocal()) {
+ // Implicitly-generated labels may end up getting generated in an order that
+ // isn't strictly lexical, which breaks name lookup. Be careful to insert
+ // the label at the appropriate place in the identifier chain.
+ for (I = IdResolver.begin(D->getDeclName()); I != IEnd; ++I) {
+ if ((*I)->getLexicalDeclContext()->Encloses(CurContext))
+ break;
+ }
+
+ IdResolver.InsertDecl(I, D);
+ } else {
+ IdResolver.AddDecl(D);
+ }
}
bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S,
diff --git a/test/SemaCXX/goto.cpp b/test/SemaCXX/goto.cpp
new file mode 100644
index 0000000..2db9d97
--- /dev/null
+++ b/test/SemaCXX/goto.cpp
@@ -0,0 +1,18 @@
+// RUN: %clang_cc1 -fsyntax-only -verify %s
+
+// PR9463
+double *end;
+void f() {
+ {
+ int end = 0;
+ goto end;
+ end = 1;
+ }
+
+ end:
+ return;
+}
+
+void g() {
+ end = 1; // expected-error{{assigning to 'double *' from incompatible type 'int'}}
+}