Restore vbase offsets for classes without a primary.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@79402 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGCXX.cpp b/lib/CodeGen/CGCXX.cpp
index f95aa28..6c054ea 100644
--- a/lib/CodeGen/CGCXX.cpp
+++ b/lib/CodeGen/CGCXX.cpp
@@ -784,7 +784,7 @@
 
     // The virtual base offsets come first...
     // FIXME: Audit, is this right?
-    if (forPrimary || !PrimaryBaseWasVirtual) {
+    if (PrimaryBase == 0 || forPrimary || !PrimaryBaseWasVirtual) {
       llvm::SmallSet<const CXXRecordDecl *, 32> SeenVBase;
       std::vector<llvm::Constant *> offsets;
       GenerateVBaseOffsets(offsets, RD, SeenVBase, Offset, Layout);