From: Fariborz Jahanian <fjahanian@apple.com>
Date: Sat, 26 Oct 2013 00:35:39 +0000 (+0000)
Subject: ObjectiveC arc. Warn when an implicitly 'strong' property
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=9d9a9436246160fe1dc3fe768ba5f69874d4b6ed;p=clang

ObjectiveC arc. Warn when an implicitly 'strong' property
is redeclared as 'weak' in class extension.
// rdar://15304886


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@193453 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index e2fedbbbab..c90b54600a 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -678,6 +678,10 @@ def warn_objc_property_default_assign_on_object : Warning<
   InGroup<ObjCPropertyNoAttribute>;
 def warn_property_attr_mismatch : Warning<
   "property attribute in class extension does not match the primary class">;
+def warn_property_implicitly_mismatched : Warning <
+  "primary property declaration is implicitly strong while redeclaration "
+  "in class extension is weak">,
+  InGroup<DiagGroup<"objc-property-implicit-mismatch">>;
 def warn_objc_property_copy_missing_on_block : Warning<
     "'copy' attribute must be specified for the block property "
     "when -fobjc-gc-only is specified">;
diff --git a/lib/Sema/SemaObjCProperty.cpp b/lib/Sema/SemaObjCProperty.cpp
index 8658b687c1..9d18c659c2 100644
--- a/lib/Sema/SemaObjCProperty.cpp
+++ b/lib/Sema/SemaObjCProperty.cpp
@@ -459,6 +459,20 @@ Sema::HandlePropertyInClassExtension(Scope *S,
       Diag(AtLoc, diag::warn_property_attr_mismatch);
       Diag(PIDecl->getLocation(), diag::note_property_declare);
     }
+    else if (getLangOpts().ObjCAutoRefCount) {
+      QualType PrimaryPropertyQT =
+        Context.getCanonicalType(PIDecl->getType()).getUnqualifiedType();
+      if (isa<ObjCObjectPointerType>(PrimaryPropertyQT)) {
+        Qualifiers::ObjCLifetime PrimaryPropertyLifeTime =
+          PrimaryPropertyQT.getObjCLifetime();
+        if (PrimaryPropertyLifeTime == Qualifiers::OCL_None &&
+            (Attributes & ObjCDeclSpec::DQ_PR_weak)) {
+              Diag(AtLoc, diag::warn_property_implicitly_mismatched);
+              Diag(PIDecl->getLocation(), diag::note_property_declare);
+            }
+        }
+    }
+    
     DeclContext *DC = cast<DeclContext>(CCPrimary);
     if (!ObjCPropertyDecl::findPropertyDecl(DC,
                                  PIDecl->getDeclName().getAsIdentifierInfo())) {
diff --git a/test/SemaObjC/arc-decls.m b/test/SemaObjC/arc-decls.m
index 3d0ef686f9..f8e80c7819 100644
--- a/test/SemaObjC/arc-decls.m
+++ b/test/SemaObjC/arc-decls.m
@@ -105,3 +105,16 @@ struct __attribute__((objc_ownership(none))) S2 {}; // expected-error {{'objc_ow
 @interface I2
     @property __attribute__((objc_ownership(frob))) id i; // expected-warning {{'objc_ownership' attribute argument not supported: 'frob'}}
 @end
+
+// rdar://15304886
+@interface NSObject @end
+
+@interface ControllerClass : NSObject @end
+
+@interface SomeClassOwnedByController
+@property (readonly) ControllerClass *controller; // expected-note {{property declared here}}
+@end
+
+@interface SomeClassOwnedByController ()
+@property (readwrite, weak) ControllerClass *controller; // expected-warning {{primary property declaration is implicitly strong while redeclaration in class extension is weak}}
+@end