When a class contains a non-empty anonymous union or struct, mark is

as non-empty. Fixes PR7021.

llvm-svn: 102913

2 files changed, 30 insertions, 3 deletions

diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index 3e4c923285c..eb91ec61472 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -1773,8 +1773,11 @@ Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS,
                              TInfo,
                              /*BitWidth=*/0, /*Mutable=*/false);
     Anon->setAccess(AS_public);
-    if (getLangOptions().CPlusPlus)
+    if (getLangOptions().CPlusPlus) {
       FieldCollector->Add(cast<FieldDecl>(Anon));
+      if (!cast<CXXRecordDecl>(Record)->isEmpty())
+        cast<CXXRecordDecl>(OwningClass)->setEmpty(false);
+    }
   } else {
     DeclSpec::SCS SCSpec = DS.getStorageClassSpec();
     assert(SCSpec != DeclSpec::SCS_typedef &&
@@ -1802,7 +1805,7 @@ Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS,
   // context. We'll be referencing this object when we refer to one of
   // its members.
   Owner->addDecl(Anon);
-
+  
   // Inject the members of the anonymous struct/union into the owning
   // context and into the identifier resolver chain for name lookup
   // purposes.
diff --git a/clang/test/CodeGenCXX/anonymous-union-member-initializer.cpp b/clang/test/CodeGenCXX/anonymous-union-member-initializer.cpp
index ea3eafc9955..adb395021e7 100644
--- a/clang/test/CodeGenCXX/anonymous-union-member-initializer.cpp
+++ b/clang/test/CodeGenCXX/anonymous-union-member-initializer.cpp
@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -emit-llvm -o - %s
+// RUN: %clang_cc1 -triple x86_64-apple-darwin10 -emit-llvm -o - %s
 
 struct A {
   union {
@@ -10,3 +10,27 @@ struct A {
 };
 
 A a;
+
+namespace PR7021 {
+  struct X
+  {
+    union { long l; };
+  };
+
+  // CHECK: define void @_ZN6PR70211fENS_1XES0_
+  void f(X x, X z) {
+    X x1;
+
+    // CHECK: store i64 1, i64
+    x1.l = 1;
+
+    // CHECK: call void @llvm.memcpy.p0i8.p0i8.i64
+    X x2(x1);
+
+    X x3;
+    // CHECK: call void @llvm.memcpy.p0i8.p0i8.i64
+    x3 = x1;
+
+    // CHECK: ret void
+  }
+}