r180211 - Objective-C arc: Improve disgnostics when 'weak'

[Fariborz Jahanian]

Author: fjahanian
Date: Wed Apr 24 14:13:05 2013
New Revision: 180211

URL: http://llvm.org/viewvc/llvm-project?rev=180211&view=rev
Log:
Objective-C arc: Improve disgnostics when 'weak'
property cannot be synthesized because its backing
ivar does not support weak references.
// rdar://13676793

Modified:
    cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td
    cfe/trunk/lib/Sema/SemaObjCProperty.cpp
    cfe/trunk/test/SemaObjC/arc-unavailable-for-weakref.m

Modified: cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td?rev=180211&r1=180210&r2=180211&view=diff
==============================================================================
--- cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td (original)
+++ cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td Wed Apr 24 14:13:05 2013
@@ -3789,8 +3789,10 @@ def err_arc_unsupported_weak_class : Err
 def err_arc_weak_unavailable_assign : Error<
   "assignment of a weak-unavailable object to a __weak object">;
 def err_arc_weak_unavailable_property : Error<
-  "synthesis of a weak-unavailable property is disallowed "
-  "because it requires synthesis of an instance variable of the __weak object">;
+  "synthesizing __weak instance variable of type %0, which does not "
+  "support weak references">;
+def note_implemented_by_class : Note<
+  "when implemented by class %0">;
 def err_arc_convesion_of_weak_unavailable : Error<
   "%select{implicit conversion|cast}0 of weak-unavailable object of type %1 to"
   " a __weak object of type %2">;

Modified: cfe/trunk/lib/Sema/SemaObjCProperty.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaObjCProperty.cpp?rev=180211&r1=180210&r2=180211&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaObjCProperty.cpp (original)
+++ cfe/trunk/lib/Sema/SemaObjCProperty.cpp Wed Apr 24 14:13:05 2013
@@ -996,8 +996,10 @@ Decl *Sema::ActOnPropertyImplDecl(Scope
                 PropertyIvarType->getAs<ObjCObjectPointerType>()) {
               const ObjCInterfaceDecl *ObjI = ObjT->getInterfaceDecl();
               if (ObjI && ObjI->isArcWeakrefUnavailable()) {
-                Diag(PropertyDiagLoc, diag::err_arc_weak_unavailable_property);
-                Diag(property->getLocation(), diag::note_property_declare);
+                Diag(property->getLocation(),
+                     diag::err_arc_weak_unavailable_property) << PropertyIvarType;
+                Diag(ClassImpDecl->getLocation(), diag::note_implemented_by_class)
+                  << ClassImpDecl->getName();
                 err = true;
               }
             }

Modified: cfe/trunk/test/SemaObjC/arc-unavailable-for-weakref.m
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaObjC/arc-unavailable-for-weakref.m?rev=180211&r1=180210&r2=180211&view=diff
==============================================================================
--- cfe/trunk/test/SemaObjC/arc-unavailable-for-weakref.m (original)
+++ cfe/trunk/test/SemaObjC/arc-unavailable-for-weakref.m Wed Apr 24 14:13:05 2013
@@ -56,9 +56,33 @@ __attribute__((objc_arc_weak_reference_u
 @interface I
 {
 }
- at property (weak) NSFont *font; // expected-note {{property declared here}}
+ at property (weak) NSFont *font; // expected-error {{synthesizing __weak instance variable of type 'NSFont *', which does not support weak references}}
 @end
 
- at implementation I
- at synthesize font = _font; // expected-error {{synthesis of a weak-unavailable property is disallowed because it requires synthesis of an instance variable of the __weak object}}
+ at implementation I // expected-note {{when implemented by class I}}
+ at synthesize font = _font;
+ at end
+
+// rdar://13676793
+ at protocol MyProtocol
+ at property (weak) NSFont *font; // expected-error {{synthesizing __weak instance variable of type 'NSFont *', which does not support weak references}}
+ at end
+
+ at interface I1 <MyProtocol>
+ at end
+
+ at implementation I1 // expected-note {{when implemented by class I1}}
+ at synthesize font = _font;
+ at end
+
+ at interface Super
+ at property (weak) NSFont *font;  // expected-error {{synthesizing __weak instance variable of type 'NSFont *', which does not support weak references}}
+ at end
+
+
+ at interface I2 : Super
+ at end
+
+ at implementation I2 // expected-note {{when implemented by class I2}}
+ at synthesize font = _font;
 @end