From edc08821d3f73514291b339db29aca1a17485e39 Mon Sep 17 00:00:00 2001
From: Fariborz Jahanian <fjahanian@apple.com>
Date: Wed, 7 Sep 2011 16:24:21 +0000
Subject: [PATCH] objc-gc: More sema work for properties declared 'weak' in GC
 mode. // rdar://10073896

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@139235 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/clang/Basic/DiagnosticSemaKinds.td |  3 +++
 lib/Sema/SemaObjCProperty.cpp              | 19 +++++++++++++------
 test/SemaObjC/error-property-gc-attr.m     |  2 +-
 3 files changed, 17 insertions(+), 7 deletions(-)

diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index e39a2c72f3..a90849cc19 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -549,6 +549,9 @@ def err_arc_perform_selector_retains : Error<
 def warn_arc_perform_selector_leaks : Warning<
   "performSelector may cause a leak because its selector is unknown">,
   InGroup<DiagGroup<"arc-performSelector-leaks">>;
+def err_gc_weak_property_strong_type : Error<
+  "weak attribute declared on a __strong type property"
+  "in GC mode">;
 
 def error_synthesized_ivar_yet_not_supported : Error<
   "instance variable synthesis not yet supported"
diff --git a/lib/Sema/SemaObjCProperty.cpp b/lib/Sema/SemaObjCProperty.cpp
index 9695b811ee..9f50dea233 100644
--- a/lib/Sema/SemaObjCProperty.cpp
+++ b/lib/Sema/SemaObjCProperty.cpp
@@ -594,12 +594,18 @@ Decl *Sema::ActOnPropertyImplDecl(Scope *S,
     ObjCPropertyDecl::PropertyAttributeKind kind 
       = property->getPropertyAttributes();
     QualType PropType = Context.getCanonicalType(property->getType());
-    bool PropertyIsGCWeak = (kind & ObjCPropertyDecl::OBJC_PR_weak &&
-                             !getLangOptions().ObjCAutoRefCount &&
-                             getLangOptions().getGCMode() != 
-                             LangOptions::NonGC);
-    if (PropertyIsGCWeak && !PropType.isObjCGCStrong())
-      PropType = Context.getObjCGCQualType(PropType, Qualifiers::Weak);
+    
+    if ((kind & ObjCPropertyDecl::OBJC_PR_weak) &&
+        !getLangOptions().ObjCAutoRefCount &&
+        getLangOptions().getGCMode() != LangOptions::NonGC) {
+      if (PropType.isObjCGCStrong()) {
+          Diag(PropertyLoc,
+               diag::err_gc_weak_property_strong_type);
+          Diag(property->getLocation(), diag::note_property_declare);    
+      }
+      else
+        PropType = Context.getObjCGCQualType(PropType, Qualifiers::Weak);
+    }
     QualType PropertyIvarType = PropType;
     if (PropType->isReferenceType())
       PropertyIvarType = cast<ReferenceType>(PropType)->getPointeeType();
@@ -721,6 +727,7 @@ Decl *Sema::ActOnPropertyImplDecl(Scope *S,
            getLangOptions().getGCMode() != LangOptions::NonGC)) {
         Diag(PropertyLoc, diag::error_weak_property)
         << property->getDeclName() << Ivar->getDeclName();
+        Diag(Ivar->getLocation(), diag::note_ivar_decl);
         // Fall thru - see previous comment
       }
       // Fall thru - see previous comment
diff --git a/test/SemaObjC/error-property-gc-attr.m b/test/SemaObjC/error-property-gc-attr.m
index 829c082287..25fee05117 100644
--- a/test/SemaObjC/error-property-gc-attr.m
+++ b/test/SemaObjC/error-property-gc-attr.m
@@ -3,7 +3,7 @@
 
 @interface INTF
 {
-  id IVAR;
+  id IVAR; // expected-note {{ivar is declared here}}
   __weak id II;
   __weak id WID;
   id ID;
-- 
2.40.0