Fix an ambiguous overload issue pointed out by MSVC

Log:
http://lab.llvm.org:8011/builders/clang-x64-ninja-win7/builds/11390

llvm-svn: 335577

1 files changed, 2 insertions, 1 deletions

diff --git a/clang/lib/Sema/SemaLambda.cpp b/clang/lib/Sema/SemaLambda.cpp
index 98b428b0899..fcacc2a17c9 100644
--- a/clang/lib/Sema/SemaLambda.cpp
+++ b/clang/lib/Sema/SemaLambda.cpp
@@ -712,7 +712,8 @@ void Sema::deduceClosureReturnType(CapturingScopeInfo &CSI) {
       auto RetTyNullability = ReturnType->getNullability(Ctx);
       auto BlockNullability = CSI.ReturnType->getNullability(Ctx);
       if (BlockNullability &&
-          (!RetTyNullability || *RetTyNullability < *BlockNullability))
+          (!RetTyNullability ||
+           hasWeakerNullability(*RetTyNullability, *BlockNullability)))
         CSI.ReturnType = ReturnType;
       continue;
     }