Change warning to error when property setter names conflict.

// rdar://11528439


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@157517 91177308-0d34-0410-b5e6-96231b3b80d8

include/clang/Basic/DiagnosticSemaKinds.td

@@ -626,10 +626,9 @@ def warn_missing_explicit_synthesis : Warning <
 def warn_property_getter_owning_mismatch : Warning<
   "property declared as returning non-retained objects"
   "; getter returning retained objects">;
-def warn_property_setter_ambiguous_use : Warning<
+def error_property_setter_ambiguous_use : Error<
   "synthesized properties '%0' and '%1' both claim setter %2 -"
-  " use of this setter may cause unexpected behavior">,
-  InGroup<DiagGroup<"objc-multiple-property-setter-use">>;
+  " use of this setter will cause unexpected behavior">;
 def err_ownin_getter_rule : Error<
   "property's synthesized getter follows Cocoa naming"
   " convention for returning 'owned' objects">;

lib/Sema/SemaPseudoObject.cpp

@@ -543,7 +543,7 @@ bool ObjCPropertyOpBuilder::findSetter(bool warn) {
         IdentifierInfo *AltMember = &S.PP.getIdentifierTable().get(PropertyName);
         if (ObjCPropertyDecl *prop1 = IFace->FindPropertyDeclaration(AltMember))
           if (prop != prop1 && (prop1->getSetterMethodDecl() == setter)) {
-            S.Diag(RefExpr->getExprLoc(), diag::warn_property_setter_ambiguous_use)
+            S.Diag(RefExpr->getExprLoc(), diag::error_property_setter_ambiguous_use)
               << prop->getName() << prop1->getName() << setter->getSelector();
             S.Diag(prop->getLocation(), diag::note_property_declare);
             S.Diag(prop1->getLocation(), diag::note_property_declare);

test/SemaObjC/property-user-setter.m

@@ -127,10 +127,10 @@ int main (void) {
   self.P = 0; // expected-error {{property 'P' not found on object of type 'rdar11363363 *'}}
   self.q = 0; // expected-error {{property 'q' not found on object of type 'rdar11363363 *'}}
 // rdar://11528439
-  self.t = 0; // expected-warning {{synthesized properties 't' and 'T' both claim setter 'setT:'}}
-  self.T = 0; // expected-warning {{synthesized properties 'T' and 't' both claim setter 'setT:'}}
-  self.Pxyz = 0; // expected-warning {{synthesized properties 'Pxyz' and 'pxyz' both claim setter 'setPxyz:'}}
-  self.pxyz = 0; // expected-warning {{synthesized properties 'pxyz' and 'Pxyz' both claim setter 'setPxyz:'}}
+  self.t = 0; // expected-error {{synthesized properties 't' and 'T' both claim setter 'setT:'}}
+  self.T = 0; // expected-error {{synthesized properties 'T' and 't' both claim setter 'setT:'}}
+  self.Pxyz = 0; // expected-error {{synthesized properties 'Pxyz' and 'pxyz' both claim setter 'setPxyz:'}}
+  self.pxyz = 0; // expected-error {{synthesized properties 'pxyz' and 'Pxyz' both claim setter 'setPxyz:'}}
   self.R = 0; // expected-error {{property 'R' not found on object of type 'rdar11363363 *'; did you mean to access ivar 'R'?}}
   return self.R; // expected-error {{property 'R' not found on object of type 'rdar11363363 *'; did you mean to access ivar 'R'?}}
 }