[Sema][ObjC] Don't warn about an implicitly retained self if the

retaining block and all of the enclosing blocks are non-escaping.

If the block implicitly retaining self doesn't escape, there is no risk
of creating retain cycles, so clang shouldn't diagnose it and force
users to add self-> to silence the diagnostic.

Also, fix a bug where clang was failing to diagnose an implicitly
retained self inside a c++ lambda nested inside a block.

rdar://problem/25059955

Differential Revision: https://reviews.llvm.org/D60736

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@358624 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 3 insertions, 5 deletions

diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index ef39092821..e64eeecb2a 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -2575,11 +2575,9 @@ Sema::LookupInObjCMethod(LookupResult &Lookup, Scope *S,
             !Diags.isIgnored(diag::warn_arc_repeated_use_of_weak, Loc))
           getCurFunction()->recordUseOfWeak(Result);
       }
-      if (getLangOpts().ObjCAutoRefCount) {
-        if (CurContext->isClosure())
-          Diag(Loc, diag::warn_implicitly_retains_self)
-            << FixItHint::CreateInsertion(Loc, "self->");
-      }
+      if (getLangOpts().ObjCAutoRefCount)
+        if (const BlockDecl *BD = CurContext->getInnermostBlockDecl())
+          ImplicitlyRetainedSelfLocs.push_back({Loc, BD});
 
       return Result;
     }