4 files changed, 29 insertions, 8 deletions
diff --git a/clang/lib/AST/RecordLayoutBuilder.cpp b/clang/lib/AST/RecordLayoutBuilder.cpp
index e3581d88d24..a60a72b74fa 100644
--- a/clang/lib/AST/RecordLayoutBuilder.cpp
+++ b/clang/lib/AST/RecordLayoutBuilder.cpp
@@ -24,11 +24,19 @@ ASTRecordLayoutBuilder::ASTRecordLayoutBuilder(ASTContext &Ctx)
   : Ctx(Ctx), Size(0), Alignment(8), StructPacking(0), NextOffset(0),
   IsUnion(false), NonVirtualSize(0), NonVirtualAlignment(8) {}
 
+void ASTRecordLayoutBuilder::LayoutVtable(const CXXRecordDecl *RD) {
+  if (RD->isPolymorphic())
+    {
+      assert (RD->getNumBases() == 0 && "no polymorphic inheritance yet");
+      int AS = 0;
+      UpdateAlignment(Ctx.Target.getPointerAlign(AS));
+      Size += Ctx.Target.getPointerWidth(AS);
+      NextOffset = Size;
+    }
+}
+
 void 
 ASTRecordLayoutBuilder::LayoutNonVirtualBases(const CXXRecordDecl *RD) {
-  assert(!RD->isPolymorphic() && 
-         "FIXME: We don't support polymorphic classes yet!");
-  
   for (CXXRecordDecl::base_class_const_iterator i = RD->bases_begin(),
        e = RD->bases_end(); i != e; ++i) {
     if (!i->isVirtual()) {
@@ -74,14 +82,20 @@ void ASTRecordLayoutBuilder::Layout(const RecordDecl *D) {
     UpdateAlignment(AA->getAlignment());
 
   // If this is a C++ class, lay out the nonvirtual bases.
-  if (Ctx.getLangOptions().CPlusPlus)
-    LayoutNonVirtualBases(cast<CXXRecordDecl>(D));
+  if (Ctx.getLangOptions().CPlusPlus) {
+    const CXXRecordDecl *RD = cast<CXXRecordDecl>(D);
+    LayoutVtable(RD);
+    LayoutNonVirtualBases(RD);
+
+    assert (RD->getNumVBases() == 0
+            && "FIXME: We don't support virtual bases yet!");
+  }
 
   LayoutFields(D);
   
   NonVirtualSize = Size;
   NonVirtualAlignment = Alignment;
-  
+
   // Finally, round the size of the total struct up to the alignment of the
   // struct itself.
   FinishLayout();
diff --git a/clang/lib/AST/RecordLayoutBuilder.h b/clang/lib/AST/RecordLayoutBuilder.h
index e7d49b55a8e..41c002d61dc 100644
--- a/clang/lib/AST/RecordLayoutBuilder.h
+++ b/clang/lib/AST/RecordLayoutBuilder.h
@@ -48,6 +48,7 @@ class ASTRecordLayoutBuilder {
   void LayoutFields(const RecordDecl *D);
   void LayoutField(const FieldDecl *D);
 
+  void LayoutVtable(const CXXRecordDecl *RD);
   void LayoutNonVirtualBases(const CXXRecordDecl *RD);
   void LayoutNonVirtualBase(const CXXRecordDecl *RD);
   
diff --git a/clang/lib/CodeGen/CodeGenTypes.cpp b/clang/lib/CodeGen/CodeGenTypes.cpp
index f88ed048fd3..c20e90e8ce6 100644
--- a/clang/lib/CodeGen/CodeGenTypes.cpp
+++ b/clang/lib/CodeGen/CodeGenTypes.cpp
@@ -381,8 +381,6 @@ const llvm::Type *CodeGenTypes::ConvertTagDeclType(const TagDecl *TD) {
 
   // FIXME. This may have to move to a better place.
   if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) {
-    assert(!RD->isPolymorphic() &&
-           "FIXME: We don't support polymorphic classes yet!");
     for (CXXRecordDecl::base_class_const_iterator i = RD->bases_begin(),
          e = RD->bases_end(); i != e; ++i) {
       if (!i->isVirtual()) {
diff --git a/clang/test/CodeGenCXX/virt.cpp b/clang/test/CodeGenCXX/virt.cpp
new file mode 100644
index 00000000000..a07d8e011f7
--- /dev/null
+++ b/clang/test/CodeGenCXX/virt.cpp
@@ -0,0 +1,8 @@
+// RUN: clang-cc %s -emit-llvm -o - -std=c++0x
+
+class A {
+public:
+  virtual void foo();
+};
+
+static_assert (sizeof (A) == (sizeof(void *)), "vtable pointer layout");