From b2ab73d93cf5f73e5e49496c36e7bc58622c7f01 Mon Sep 17 00:00:00 2001
From: Fariborz Jahanian <fjahanian@apple.com>
Date: Fri, 8 May 2009 19:36:34 +0000
Subject: [PATCH] More type checking for properties, accessors and use of
 dot-syntax expression. This is to match gcc's.

llvm-svn: 71243
---
 .../clang/Basic/DiagnosticSemaKinds.td        |  2 +-
 clang/lib/Sema/SemaDeclObjC.cpp               | 18 +++--
 clang/lib/Sema/SemaExpr.cpp                   | 17 ++++-
 clang/test/SemaObjC/property-typecheck-1.m    | 72 ++++++++++++++++++-
 4 files changed, 99 insertions(+), 10 deletions(-)

diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td
index f4da72531487..a8d079d720a7 100644
--- a/clang/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td
@@ -174,7 +174,7 @@ def warn_conflicting_param_types : Warning<
   "conflicting parameter types in implementation of %0: %1 vs %2">;
 
 def warn_multiple_method_decl : Warning<"multiple methods named %0 found">;
-def err_accessor_property_type_mismatch : Error<
+def warn_accessor_property_type_mismatch : Warning<
   "type of property %0 does not match type of accessor %1">;
 def note_declared_at : Note<"declared at">;
 def err_setter_type_void : Error<"type of setter must be void">;
diff --git a/clang/lib/Sema/SemaDeclObjC.cpp b/clang/lib/Sema/SemaDeclObjC.cpp
index e35b7a919b49..34afdedba7da 100644
--- a/clang/lib/Sema/SemaDeclObjC.cpp
+++ b/clang/lib/Sema/SemaDeclObjC.cpp
@@ -1315,11 +1315,17 @@ void Sema::ProcessPropertyDecl(ObjCPropertyDecl *property,
   
   if (GetterMethod &&
       GetterMethod->getResultType() != property->getType()) {
-    Diag(property->getLocation(), 
-         diag::err_accessor_property_type_mismatch) 
-      << property->getDeclName()
-      << GetterMethod->getSelector();
-    Diag(GetterMethod->getLocation(), diag::note_declared_at);
+    AssignConvertType result = Incompatible;
+    if (Context.isObjCObjectPointerType(property->getType()))
+      result = CheckAssignmentConstraints(property->getType(), 
+                                          GetterMethod->getResultType());
+    if (result != Compatible) {
+      Diag(property->getLocation(), 
+           diag::warn_accessor_property_type_mismatch) 
+        << property->getDeclName()
+        << GetterMethod->getSelector();
+      Diag(GetterMethod->getLocation(), diag::note_declared_at);
+    }
   }
   
   if (SetterMethod) {
@@ -1329,7 +1335,7 @@ void Sema::ProcessPropertyDecl(ObjCPropertyDecl *property,
     if (SetterMethod->param_size() != 1 ||
         ((*SetterMethod->param_begin())->getType() != property->getType())) {
       Diag(property->getLocation(), 
-           diag::err_accessor_property_type_mismatch) 
+           diag::warn_accessor_property_type_mismatch) 
         << property->getDeclName()
         << SetterMethod->getSelector();
       Diag(SetterMethod->getLocation(), diag::note_declared_at);
diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp
index 79c471a2d485..f698620543fb 100644
--- a/clang/lib/Sema/SemaExpr.cpp
+++ b/clang/lib/Sema/SemaExpr.cpp
@@ -2096,8 +2096,21 @@ Sema::ActOnMemberReferenceExpr(Scope *S, ExprArg Base, SourceLocation OpLoc,
       // Check whether we can reference this property.
       if (DiagnoseUseOfDecl(PD, MemberLoc))
         return ExprError();
-
-      return Owned(new (Context) ObjCPropertyRefExpr(PD, PD->getType(),
+      QualType ResTy = PD->getType();
+      Selector Sel = PP.getSelectorTable().getNullarySelector(&Member);
+      ObjCMethodDecl *Getter = IFace->lookupInstanceMethod(Context, Sel);
+      if (Getter) {
+        AssignConvertType result =
+          CheckAssignmentConstraints(PD->getType(), Getter->getResultType());
+        if (result != Compatible) {
+          Diag(MemberLoc, diag::warn_accessor_property_type_mismatch) 
+            << PD->getDeclName() << Sel;
+          Diag(Getter->getLocation(), diag::note_declared_at);
+          ResTy = Getter->getResultType();
+        }
+      }
+      
+      return Owned(new (Context) ObjCPropertyRefExpr(PD, ResTy,
                                                      MemberLoc, BaseExpr));
     }
 
diff --git a/clang/test/SemaObjC/property-typecheck-1.m b/clang/test/SemaObjC/property-typecheck-1.m
index 1795da8599b5..c4d7cd2448d5 100644
--- a/clang/test/SemaObjC/property-typecheck-1.m
+++ b/clang/test/SemaObjC/property-typecheck-1.m
@@ -2,7 +2,7 @@
 
 @interface A
 -(float) x;	// expected-note {{declared at}}
-@property int x; // expected-error {{type of property 'x' does not match type of accessor 'x'}}
+@property int x; // expected-warning {{type of property 'x' does not match type of accessor 'x'}}
 @end
 
 @interface A (Cat)
@@ -29,3 +29,73 @@ typedef void (F)(void);
 @end
 
 
+@class SSyncSet;
+
+@interface SPeer
+  @property(nonatomic,readonly,retain) SSyncSet* syncSet;
+@end
+
+@class SSyncSet_iDisk;
+
+@interface SPeer_iDisk_remote1 : SPeer
+- (SSyncSet_iDisk*) syncSet; // expected-note {{declared at}}
+@end
+
+@interface SPeer_iDisk_local
+- (SSyncSet_iDisk*) syncSet;
+@end
+
+@interface SSyncSet
+@end
+
+@interface SSyncSet_iDisk
+@property(nonatomic,readonly,retain) SPeer_iDisk_local* localPeer;
+@end
+
+@interface SPeer_iDisk_remote1 (protected)
+@end
+
+@implementation SPeer_iDisk_remote1 (protected)
+- (id) preferredSource1
+{
+  return self.syncSet.localPeer; // expected-warning {{type of property 'syncSet' does not match type of accessor 'syncSet'}}
+}
+@end
+
+@interface NSArray @end
+
+@interface NSMutableArray : NSArray
+@end
+
+@interface Class1 
+{
+ NSMutableArray* pieces;
+ NSArray* first;
+}
+
+@property (readonly) NSArray* pieces;
+@property (readonly) NSMutableArray* first; // expected-warning {{type of property 'first' does not match type of accessor 'first'}}
+
+- (NSMutableArray*) pieces;
+- (NSArray*) first;	// expected-note {{declared at}}  // expected-note {{declared at}}
+@end
+
+@interface Class2  {
+ Class1* container;
+}
+
+@end
+
+@implementation Class2
+
+- (id) lastPiece
+{
+ return container.pieces;
+}
+
+- (id)firstPeice
+{
+  return container.first; // expected-warning {{type of property 'first' does not match type of accessor 'first'}}
+}
+@end
+