Diagnose gc attribute mismatch of property and its ivar.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@65656 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 43 insertions, 0 deletions

diff --git a/include/clang/Basic/DiagnosticSemaKinds.def b/include/clang/Basic/DiagnosticSemaKinds.def
index af3c8672ac..e1c0af4659 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.def
+++ b/include/clang/Basic/DiagnosticSemaKinds.def
@@ -211,6 +211,10 @@ DIAG(error_missing_property_ivar_decl, ERROR,
      " ivar or must explicitly name an ivar")
 DIAG(error_property_ivar_type, ERROR,
      "type of property %0 does not match type of ivar %1") 
+DIAG(error_weak_property, ERROR,
+     "existing ivar %1 for __weak property %0 must be __weak")
+DIAG(error_strong_property, ERROR,
+     "existing ivar %1 for a __strong property %0 must be garbage collectable")
 DIAG(error_dynamic_property_ivar_decl, ERROR,
      "dynamic property can not have ivar specification")
 DIAG(error_duplicate_ivar_use, ERROR,
diff --git a/lib/Sema/SemaDeclObjC.cpp b/lib/Sema/SemaDeclObjC.cpp
index cb35890b3f..dc30ac2ea9 100644
--- a/lib/Sema/SemaDeclObjC.cpp
+++ b/lib/Sema/SemaDeclObjC.cpp
@@ -1751,6 +1751,18 @@ Sema::DeclTy *Sema::ActOnPropertyImplDecl(SourceLocation AtLoc,
           << property->getDeclName() << Ivar->getDeclName();
           return 0;
         }
+        // __weak is explicit. So it works on Canonical type.
+        if (PropType.isObjCGCWeak() && !IvarType.isObjCGCWeak()) {
+          Diag(PropertyLoc, diag::error_weak_property)
+          << property->getDeclName() << Ivar->getDeclName();
+          return 0;
+        }
+        if ((Context.isObjCObjectPointerType(property->getType()) || 
+             PropType.isObjCGCStrong()) && IvarType.isObjCGCWeak()) {
+          Diag(PropertyLoc, diag::error_strong_property)
+          << property->getDeclName() << Ivar->getDeclName();
+          return 0;
+        }
       }
     }
   } else if (PropertyIvar) {
diff --git a/test/SemaObjC/error-property-gc-attr.m b/test/SemaObjC/error-property-gc-attr.m
new file mode 100644
index 0000000000..3b646ac5f9
--- /dev/null
+++ b/test/SemaObjC/error-property-gc-attr.m
@@ -0,0 +1,27 @@
+// RUN: clang -fobjc-gc -fsyntax-only -verify %s
+
+@interface INTF
+{
+  id IVAR;
+  __weak id II;
+  __weak id WID;
+  id ID;
+  __weak INTF* AWEAK;
+  __weak INTF* WI;
+}
+@property (assign) __weak id pweak;
+@property (assign) __weak id WID;
+@property (assign) __strong id not;
+@property (assign)  id ID;
+@property (assign) INTF* AWEAK;
+@property (assign) __weak INTF* WI;
+@end	
+
+@implementation INTF
+@synthesize pweak=IVAR;  // expected-error {{existing ivar 'IVAR' for __weak property 'pweak' must be __weak}}
+@synthesize not=II; // expected-error {{existing ivar 'II' for a __strong property 'not' must be garbage collectable}}
+@synthesize WID;
+@synthesize ID;
+@synthesize AWEAK; // expected-error {{existing ivar 'AWEAK' for a __strong property 'AWEAK' must be garbage collectable}}
+@synthesize WI;
+@end