[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

llvm-svn: 358624

2 files changed, 42 insertions, 18 deletions

diff --git a/clang/test/SemaObjC/warn-implicit-self-in-block.m b/clang/test/SemaObjC/warn-implicit-self-in-block.m
deleted file mode 100644
index a7ee16ec700..00000000000
--- a/clang/test/SemaObjC/warn-implicit-self-in-block.m
+++ /dev/null
@@ -1,18 +0,0 @@
-// RUN: %clang_cc1 -x objective-c -fobjc-arc -fblocks -Wimplicit-retain-self -verify %s
-// rdar://11194874
-
-@interface Root @end
-
-@interface I : Root
-{
-  int _bar;
-}
-@end
-
-@implementation I
-  - (void)foo{
-      ^{
-           _bar = 3; // expected-warning {{block implicitly retains 'self'; explicitly mention 'self' to indicate this is intended behavior}}
-       }();
-  }
-@end
diff --git a/clang/test/SemaObjCXX/warn-implicit-self-in-block.mm b/clang/test/SemaObjCXX/warn-implicit-self-in-block.mm
new file mode 100644
index 00000000000..4842b4b10ba
--- /dev/null
+++ b/clang/test/SemaObjCXX/warn-implicit-self-in-block.mm
@@ -0,0 +1,42 @@
+// RUN: %clang_cc1 -x objective-c++ -std=c++11 -fobjc-arc -fblocks -Wimplicit-retain-self -verify %s
+// rdar://11194874
+
+typedef void (^BlockTy)();
+
+void noescapeFunc(__attribute__((noescape)) BlockTy);
+void escapeFunc(BlockTy);
+
+@interface Root @end
+
+@interface I : Root
+{
+  int _bar;
+}
+@end
+
+@implementation I
+  - (void)foo{
+      ^{
+           _bar = 3; // expected-warning {{block implicitly retains 'self'; explicitly mention 'self' to indicate this is intended behavior}}
+       }();
+  }
+
+  - (void)testNested{
+    noescapeFunc(^{
+      (void)_bar;
+      escapeFunc(^{
+        (void)_bar; // expected-warning {{block implicitly retains 'self'; explicitly mention 'self' to indicate this is intended behavior}}
+        noescapeFunc(^{
+          (void)_bar; // expected-warning {{block implicitly retains 'self'; explicitly mention 'self' to indicate this is intended behavior}}
+        });
+        (void)_bar; // expected-warning {{block implicitly retains 'self'; explicitly mention 'self' to indicate this is intended behavior}}
+      });
+      (void)_bar;
+    });
+  }
+
+  - (void)testLambdaInBlock{
+    noescapeFunc(^{ [&](){ (void)_bar; }(); });
+    escapeFunc(^{ [&](){ (void)_bar; }(); }); // expected-warning {{block implicitly retains 'self'; explicitly mention 'self' to indicate this is intended behavior}}
+  }
+@end