Make error about using bridge casts in non-ARC mode a warning that is default mapped to an error.  This is to ease the transition of large apps moving from non-ARC to ARC.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@149659 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/clang/Basic/DiagnosticParseKinds.td b/include/clang/Basic/DiagnosticParseKinds.td
index 047d6ce..73d7883 100644
--- a/include/clang/Basic/DiagnosticParseKinds.td
+++ b/include/clang/Basic/DiagnosticParseKinds.td
@@ -330,8 +330,10 @@
 let CategoryName = "ARC Parse Issue" in {
 def err_arc_bridge_retain : Error<
   "unknown cast annotation __bridge_retain; did you mean __bridge_retained?">;
-def err_arc_bridge_cast_nonarc : Error<
-  "'%0' casts are only allowed when using ARC">;
+def err_arc_bridge_cast_nonarc : Warning<
+  "'%0' casts are only allowed when using ARC">,
+  InGroup<DiagGroup<"arc-bridge-casts-disallowed-in-nonarc">>,
+  DefaultError;
 }
   
 def err_objc_illegal_visibility_spec : Error<
diff --git a/test/SemaObjC/illegal-nonarc-bridged-cast.m b/test/SemaObjC/illegal-nonarc-bridged-cast.m
index b0d1e82..fe6b24a 100644
--- a/test/SemaObjC/illegal-nonarc-bridged-cast.m
+++ b/test/SemaObjC/illegal-nonarc-bridged-cast.m
@@ -35,3 +35,10 @@
   id obj1 = (id)CFCreateSomething();
   CFTypeRef cf1 = (CFTypeRef)CreateSomething();
 }
+
+#pragma clang diagnostic ignored "-Warc-bridge-casts-disallowed-in-nonarc"
+
+void to_cf_ignored(id obj) {
+  CFTypeRef cf1 = (__bridge_retained CFTypeRef)CreateSomething(); // no-warning
+  CFTypeRef cf3 = (__bridge CFTypeRef)CreateSomething(); // no-warning
+}