Extend type nullability qualifiers for Objective-C.

Introduce context-sensitive, non-underscored nullability specifiers
(nonnull, nullable, null_unspecified) for Objective-C method return
types, method parameter types, and properties.

Introduce Objective-C-specific semantics, including computation of the
nullability of the result of a message send, merging of nullability
information from the @interface of a class into its @implementation,
etc .

This is the Objective-C part of rdar://problem/18868820.

llvm-svn: 240154

1 files changed, 6 insertions, 2 deletions

diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index f4af3f320a8..aa006b31fc8 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -2471,9 +2471,13 @@ static void mergeParamDeclTypes(ParmVarDecl *NewParam,
   if (auto Oldnullability = OldParam->getType()->getNullability(S.Context)) {
     if (auto Newnullability = NewParam->getType()->getNullability(S.Context)) {
       if (*Oldnullability != *Newnullability) {
+        unsigned unsNewnullability = static_cast<unsigned>(*Newnullability);
+        unsigned unsOldnullability = static_cast<unsigned>(*Oldnullability);
         S.Diag(NewParam->getLocation(), diag::warn_mismatched_nullability_attr)
-          << static_cast<unsigned>(*Newnullability)
-          << static_cast<unsigned>(*Oldnullability);
+          << unsNewnullability
+          << ((NewParam->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability) != 0)
+          << unsOldnullability
+          << ((OldParam->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability) != 0);
         S.Diag(OldParam->getLocation(), diag::note_previous_declaration);
       }
     }