Index: cfe/trunk/lib/Sema/SemaExprCXX.cpp
===================================================================
--- cfe/trunk/lib/Sema/SemaExprCXX.cpp
+++ cfe/trunk/lib/Sema/SemaExprCXX.cpp
@@ -4216,7 +4216,20 @@
     break;
 
   case ICK_Block_Pointer_Conversion: {
-    From = ImpCastExprToType(From, ToType.getUnqualifiedType(), CK_BitCast,
+    QualType LHSType = Context.getCanonicalType(ToType).getUnqualifiedType();
+    QualType RHSType = Context.getCanonicalType(FromType).getUnqualifiedType();
+
+    // Assumptions based on Sema::IsBlockPointerConversion.
+    assert(isa<BlockPointerType>(LHSType) && "BlockPointerType expected");
+    assert(isa<BlockPointerType>(RHSType) && "BlockPointerType expected");
+
+    LangAS AddrSpaceL =
+        LHSType->getAs<BlockPointerType>()->getPointeeType().getAddressSpace();
+    LangAS AddrSpaceR =
+        RHSType->getAs<BlockPointerType>()->getPointeeType().getAddressSpace();
+    CastKind Kind =
+        AddrSpaceL != AddrSpaceR ? CK_AddressSpaceConversion : CK_BitCast;
+    From = ImpCastExprToType(From, ToType.getUnqualifiedType(), Kind,
                              VK_RValue, /*BasePath=*/nullptr, CCK).get();
     break;
   }