From 76a11f8abd26c4c3d5f90f201962122b7b6d3e84 Mon Sep 17 00:00:00 2001
From: Douglas Gregor <doug.gregor@gmail.com>
Date: Fri, 18 Feb 2011 02:44:58 +0000
Subject: [PATCH] When building a qualified reference to a member of an
 anonymous struct or union, place the qualifier on the outermost member
 reference expression, which actually contains the entity name.

Fixes PR9188/<rdar://problem/8990184>.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@125822 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Sema/SemaExpr.cpp                             | 13 +++++++------
 test/SemaTemplate/instantiate-anonymous-union.cpp | 21 +++++++++++++++++++++
 2 files changed, 28 insertions(+), 6 deletions(-)

diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index 2b1b8b290..92e671165 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -1004,6 +1004,7 @@ Sema::BuildAnonymousStructUnionMemberReference(const CXXScopeSpec &SS,
 
   // Case 1:  the base of the indirect field is not a field.
   VarDecl *baseVariable = indirectField->getVarDecl();
+  CXXScopeSpec EmptySS;
   if (baseVariable) {
     assert(baseVariable->getType()->isRecordType());
 
@@ -1017,7 +1018,7 @@ Sema::BuildAnonymousStructUnionMemberReference(const CXXScopeSpec &SS,
     DeclarationNameInfo baseNameInfo(DeclarationName(), loc);
 
     ExprResult result =
-      BuildDeclarationNameExpr(SS, baseNameInfo, baseVariable);
+      BuildDeclarationNameExpr(EmptySS, baseNameInfo, baseVariable);
     if (result.isInvalid()) return ExprError();
 
     baseObjectExpr = result.take();    
@@ -1078,7 +1079,7 @@ Sema::BuildAnonymousStructUnionMemberReference(const CXXScopeSpec &SS,
     DeclarationNameInfo memberNameInfo(field->getDeclName(), loc);
 
     result = BuildFieldReferenceExpr(*this, result, baseObjectIsPointer,
-                                     SS, field, foundDecl,
+                                     EmptySS, field, foundDecl,
                                      memberNameInfo).take();
     baseObjectIsPointer = false;
 
@@ -1088,16 +1089,16 @@ Sema::BuildAnonymousStructUnionMemberReference(const CXXScopeSpec &SS,
   // In all cases, we should now skip the first declaration in the chain.
   ++FI;
 
-  for (; FI != FEnd; FI++) {
-    FieldDecl *field = cast<FieldDecl>(*FI);
+  while (FI != FEnd) {
+    FieldDecl *field = cast<FieldDecl>(*FI++);
 
     // FIXME: these are somewhat meaningless
     DeclarationNameInfo memberNameInfo(field->getDeclName(), loc);
     DeclAccessPair foundDecl = DeclAccessPair::make(field, field->getAccess());
-    CXXScopeSpec memberSS;
 
     result = BuildFieldReferenceExpr(*this, result, /*isarrow*/ false,
-                                     memberSS, field, foundDecl, memberNameInfo)
+                                     (FI == FEnd? SS : EmptySS), field, 
+                                     foundDecl, memberNameInfo)
       .take();
   }
 
diff --git a/test/SemaTemplate/instantiate-anonymous-union.cpp b/test/SemaTemplate/instantiate-anonymous-union.cpp
index f2862db6b..68b233a7f 100644
--- a/test/SemaTemplate/instantiate-anonymous-union.cpp
+++ b/test/SemaTemplate/instantiate-anonymous-union.cpp
@@ -66,3 +66,24 @@ namespace PR7402 {
 
   X x(42.0);
 }
+
+namespace PR9188 {
+  struct X0 {
+    union {
+      int member;
+    };
+  };
+
+  static union {
+    int global;
+  };
+
+  struct X1 : X0 {
+    template<typename T>
+    int f() {
+      return this->X0::member + PR9188::global;
+    }
+  };
+
+  template int X1::f<int>();
+}
-- 
2.11.4.GIT