Index: clang/lib/CodeGen/CGClass.cpp
===================================================================
--- clang/lib/CodeGen/CGClass.cpp
+++ clang/lib/CodeGen/CGClass.cpp
@@ -2502,6 +2502,8 @@
 
   // Apply the offsets.
   Address VTableField = LoadCXXThisAddress();
+  unsigned ThisAddrSpace =
+      VTableField.getPointer()->getType()->getPointerAddressSpace();
 
   if (!NonVirtualOffset.isZero() || VirtualOffset)
     VTableField = ApplyNonVirtualAndVirtualOffset(
@@ -2516,10 +2518,11 @@
       llvm::FunctionType::get(CGM.Int32Ty, /*isVarArg=*/true)
           ->getPointerTo(ProgAS)
           ->getPointerTo(GlobalsAS);
-  // vtable field is is derived from `this` pointer, therefore it should be in
-  // default address space.
+  // vtable field is is derived from `this` pointer, therefore they should be in
+  // the same addr space. Note it may not be the default address space of LLVM
+  // IR.
   VTableField = Builder.CreatePointerBitCastOrAddrSpaceCast(
-      VTableField, VTablePtrTy->getPointerTo());
+      VTableField, VTablePtrTy->getPointerTo(ThisAddrSpace));
   VTableAddressPoint = Builder.CreatePointerBitCastOrAddrSpaceCast(
       VTableAddressPoint, VTablePtrTy);