From c3f48cd3f08c384de50a3eeceaa79f4800a35f19 Mon Sep 17 00:00:00 2001
From: Fariborz Jahanian <fjahanian@apple.com>
Date: Mon, 14 Sep 2009 16:40:48 +0000
Subject: [PATCH] Using the property dot-syntax to invoke a non-eixsting
 structure-valued setter should cause a user error instead of crash.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@81769 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/AST/Expr.cpp                              | 19 ++++++++-------
 .../SemaObjC/property-error-readonly-assign.m | 23 +++++++++++++++++++
 2 files changed, 32 insertions(+), 10 deletions(-)

diff --git a/lib/AST/Expr.cpp b/lib/AST/Expr.cpp
index fa020de7a3..620b5b8901 100644
--- a/lib/AST/Expr.cpp
+++ b/lib/AST/Expr.cpp
@@ -1061,12 +1061,18 @@ Expr::isModifiableLvalue(ASTContext &Ctx, SourceLocation *Loc) const {
   //   void takeclosure(void (^C)(void));
   //   void func() { int x = 1; takeclosure(^{ x = 7; }); }
   //
-  if (isa<BlockDeclRefExpr>(this)) {
-    const BlockDeclRefExpr *BDR = cast<BlockDeclRefExpr>(this);
+  if (const BlockDeclRefExpr *BDR = dyn_cast<BlockDeclRefExpr>(this)) {
     if (!BDR->isByRef() && isa<VarDecl>(BDR->getDecl()))
       return MLV_NotBlockQualified;
   }
-
+  
+  // Assigning to an 'implicit' property?
+  if (const ObjCImplicitSetterGetterRefExpr* Expr = 
+        dyn_cast<ObjCImplicitSetterGetterRefExpr>(this)) {
+    if (Expr->getSetterMethod() == 0)
+      return MLV_NoSetterProperty;
+  }
+  
   QualType CT = Ctx.getCanonicalType(getType());
 
   if (CT.isConstQualified())
@@ -1081,13 +1087,6 @@ Expr::isModifiableLvalue(ASTContext &Ctx, SourceLocation *Loc) const {
       return MLV_ConstQualified;
   }
 
-  // Assigning to an 'implicit' property?
-  else if (isa<ObjCImplicitSetterGetterRefExpr>(this)) {
-    const ObjCImplicitSetterGetterRefExpr* Expr =
-      cast<ObjCImplicitSetterGetterRefExpr>(this);
-    if (Expr->getSetterMethod() == 0)
-      return MLV_NoSetterProperty;
-  }
   return MLV_Valid;
 }
 
diff --git a/test/SemaObjC/property-error-readonly-assign.m b/test/SemaObjC/property-error-readonly-assign.m
index edeff09dfa..d5cef78f18 100644
--- a/test/SemaObjC/property-error-readonly-assign.m
+++ b/test/SemaObjC/property-error-readonly-assign.m
@@ -19,3 +19,26 @@ void f0(A *a, B* b) {
   b.ok = 20;
 }
 
+typedef struct {
+  int i1, i2;
+} NSRect;
+
+NSRect NSMakeRect();
+
+@interface NSWindow 
+{
+    NSRect _frame;
+}
+- (NSRect)frame;
+@end
+
+@interface NSWindow (Category)
+-(void)methodToMakeClangCrash;
+@end
+
+@implementation NSWindow (Category)
+-(void)methodToMakeClangCrash
+{
+ self.frame =  NSMakeRect(); // expected-error {{setter method is needed to assign to object using property assignment syntax}}
+}
+@end
-- 
2.40.0