From 744147138cd2a77320c431578da130cc3d81a1d5 Mon Sep 17 00:00:00 2001
From: Fariborz Jahanian <fjahanian@apple.com>
Date: Tue, 15 May 2012 18:12:51 +0000
Subject: [PATCH] objc: avoid duplicate diagnostics on certain type mismatches
 between property and its backing ivar.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@156832 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Sema/SemaObjCProperty.cpp          | 34 ++++++++++++++------------
 test/SemaObjC/property-ivar-mismatch.m | 12 +++++++++
 2 files changed, 30 insertions(+), 16 deletions(-)

diff --git a/lib/Sema/SemaObjCProperty.cpp b/lib/Sema/SemaObjCProperty.cpp
index 5a98077bd7..e826b47784 100644
--- a/lib/Sema/SemaObjCProperty.cpp
+++ b/lib/Sema/SemaObjCProperty.cpp
@@ -658,6 +658,7 @@ Decl *Sema::ActOnPropertyImplDecl(Scope *S,
   }
   ObjCIvarDecl *Ivar = 0;
   bool CompleteTypeErr = false;
+  bool compat = true;
   // Check that we have a valid, previously declared ivar for @synthesize
   if (Synthesize) {
     // @synthesize
@@ -773,8 +774,8 @@ Decl *Sema::ActOnPropertyImplDecl(Scope *S,
     QualType IvarType = Context.getCanonicalType(Ivar->getType());
 
     // Check that type of property and its ivar are type compatible.
-    if (Context.getCanonicalType(PropertyIvarType) != IvarType) {
-      bool compat = false;
+    if (!Context.hasSameType(PropertyIvarType, IvarType)) {
+      compat = false;
       if (isa<ObjCObjectPointerType>(PropertyIvarType) 
           && isa<ObjCObjectPointerType>(IvarType))
         compat = 
@@ -794,19 +795,20 @@ Decl *Sema::ActOnPropertyImplDecl(Scope *S,
         // Note! I deliberately want it to fall thru so, we have a
         // a property implementation and to avoid future warnings.
       }
-
-      // FIXME! Rules for properties are somewhat different that those
-      // for assignments. Use a new routine to consolidate all cases;
-      // specifically for property redeclarations as well as for ivars.
-      QualType lhsType =Context.getCanonicalType(PropertyIvarType).getUnqualifiedType();
-      QualType rhsType =Context.getCanonicalType(IvarType).getUnqualifiedType();
-      if (lhsType != rhsType &&
-          lhsType->isArithmeticType()) {
-        Diag(PropertyDiagLoc, diag::error_property_ivar_type)
-          << property->getDeclName() << PropType
-          << Ivar->getDeclName() << IvarType;
-        Diag(Ivar->getLocation(), diag::note_ivar_decl);
-        // Fall thru - see previous comment
+      else {
+        // FIXME! Rules for properties are somewhat different that those
+        // for assignments. Use a new routine to consolidate all cases;
+        // specifically for property redeclarations as well as for ivars.
+        QualType lhsType =Context.getCanonicalType(PropertyIvarType).getUnqualifiedType();
+        QualType rhsType =Context.getCanonicalType(IvarType).getUnqualifiedType();
+        if (lhsType != rhsType &&
+            lhsType->isArithmeticType()) {
+          Diag(PropertyDiagLoc, diag::error_property_ivar_type)
+            << property->getDeclName() << PropType
+            << Ivar->getDeclName() << IvarType;
+          Diag(Ivar->getLocation(), diag::note_ivar_decl);
+          // Fall thru - see previous comment
+        }
       }
       // __weak is explicit. So it works on Canonical type.
       if ((PropType.isObjCGCWeak() && !IvarType.isObjCGCWeak() &&
@@ -840,7 +842,7 @@ Decl *Sema::ActOnPropertyImplDecl(Scope *S,
                                 : ObjCPropertyImplDecl::Dynamic),
                                Ivar, PropertyIvarLoc);
 
-  if (CompleteTypeErr)
+  if (CompleteTypeErr || !compat)
     PIDecl->setInvalidDecl();
 
   if (ObjCMethodDecl *getterMethod = property->getGetterMethodDecl()) {
diff --git a/test/SemaObjC/property-ivar-mismatch.m b/test/SemaObjC/property-ivar-mismatch.m
index 6abd6e662d..a0d1c9da7b 100644
--- a/test/SemaObjC/property-ivar-mismatch.m
+++ b/test/SemaObjC/property-ivar-mismatch.m
@@ -12,3 +12,15 @@
 @synthesize prop = ivar;  // expected-error {{type of property 'prop' ('int') does not match type of ivar 'ivar' ('char')}}
 @end
 
+
+@interface Test5
+{
+  void * _P; // expected-note {{ivar is declared here}}
+}
+@property int P;
+@end
+
+@implementation Test5
+@synthesize P=_P; // expected-error {{ype of property 'P' ('int') does not match type of ivar '_P' ('void *')}}
+@end
+
-- 
2.40.0