PR17731: When determining whether a tag and a non-tag were declared in the same

scope, be careful about function-scope declarations (which are not declared in
their semantic context).

llvm-svn: 193671

1 files changed, 17 insertions, 2 deletions

diff --git a/clang/lib/Sema/SemaLookup.cpp b/clang/lib/Sema/SemaLookup.cpp
index cca0f22f14a..dba0759b183 100644
--- a/clang/lib/Sema/SemaLookup.cpp
+++ b/clang/lib/Sema/SemaLookup.cpp
@@ -337,6 +337,21 @@ void LookupResult::deletePaths(CXXBasePaths *Paths) {
   delete Paths;
 }
 
+/// Get a representative context for a declaration such that two declarations
+/// will have the same context if they were found within the same scope.
+DeclContext *getContextForScopeMatching(Decl *D) {
+  // For function-local declarations, use that function as the context. This
+  // doesn't account for scopes within the function; the caller must deal with
+  // those.
+  DeclContext *DC = D->getLexicalDeclContext();
+  if (DC->isFunctionOrMethod())
+    return DC;
+
+  // Otherwise, look at the semantic context of the declaration. The
+  // declaration must have been found there.
+  return D->getDeclContext()->getRedeclContext();
+}
+
 /// Resolves the result kind of this lookup.
 void LookupResult::resolveKind() {
   unsigned N = Decls.size();
@@ -437,8 +452,8 @@ void LookupResult::resolveKind() {
   // even if they're not visible. (ref?)
   if (HideTags && HasTag && !Ambiguous &&
       (HasFunction || HasNonFunction || HasUnresolved)) {
-    if (Decls[UniqueTagIndex]->getDeclContext()->getRedeclContext()->Equals(
-         Decls[UniqueTagIndex? 0 : N-1]->getDeclContext()->getRedeclContext()))
+    if (getContextForScopeMatching(Decls[UniqueTagIndex])->Equals(
+            getContextForScopeMatching(Decls[UniqueTagIndex ? 0 : N - 1])))
       Decls[UniqueTagIndex] = Decls[--N];
     else
       Ambiguous = true;