From 4088ec00f035cf3ced00aab7dac611ce6ec1988e Mon Sep 17 00:00:00 2001
From: Fariborz Jahanian <fjahanian@apple.com>
Date: Thu, 9 Sep 2010 23:01:10 +0000
Subject: [PATCH] property reference expression used on lhs of assignment
 follows objective's semantics and is not overload'able with an assignment
 operator. Fixes a crash and a missing diagnostics. Radar 8379892.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@113555 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/AST/ExprClassification.cpp         |  3 ++-
 lib/Sema/SemaExpr.cpp                  |  2 ++
 test/CodeGenObjCXX/property-objects.mm | 19 +++++++++++++++++++
 test/SemaObjCXX/propert-dot-error.mm   | 21 +++++++++++++++++++++
 4 files changed, 44 insertions(+), 1 deletion(-)
 create mode 100644 test/SemaObjCXX/propert-dot-error.mm

diff --git a/lib/AST/ExprClassification.cpp b/lib/AST/ExprClassification.cpp
index d7e38ebbf5..8ec81943b3 100644
--- a/lib/AST/ExprClassification.cpp
+++ b/lib/AST/ExprClassification.cpp
@@ -420,7 +420,8 @@ static Cl::ModifiableType IsModifiable(ASTContext &Ctx, const Expr *E,
 
   // Records with any const fields (recursively) are not modifiable.
   if (const RecordType *R = CT->getAs<RecordType>()) {
-    assert(!Ctx.getLangOptions().CPlusPlus &&
+    assert((isa<ObjCImplicitSetterGetterRefExpr>(E) || 
+            !Ctx.getLangOptions().CPlusPlus) &&
            "C++ struct assignment should be resolved by the "
            "copy assignment operator.");
     if (R->hasConstFields())
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index 6b3556cbaa..1836482fd8 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -6685,6 +6685,8 @@ ExprResult Sema::BuildBinOp(Scope *S, SourceLocation OpLoc,
                             BinaryOperatorKind Opc,
                             Expr *lhs, Expr *rhs) {
   if (getLangOptions().CPlusPlus &&
+      (!isa<ObjCImplicitSetterGetterRefExpr>(lhs) ||
+       rhs->isTypeDependent()) &&
       (lhs->getType()->isOverloadableType() ||
        rhs->getType()->isOverloadableType())) {
     // Find all of the overloaded operators visible from this
diff --git a/test/CodeGenObjCXX/property-objects.mm b/test/CodeGenObjCXX/property-objects.mm
index 724cf68268..8e98b0dae7 100644
--- a/test/CodeGenObjCXX/property-objects.mm
+++ b/test/CodeGenObjCXX/property-objects.mm
@@ -57,3 +57,22 @@ int main() {
   return 0;
 }
 
+// rdar://8379892
+// CHECK: define void @_Z1fP1A
+// CHECK: @objc_msgSend to void
+struct X {
+  X();
+  X(const X&);
+  ~X();
+};
+
+@interface A {
+  X xval;
+}
+- (X)x;
+- (void)setX:(X)x;
+@end
+
+void f(A* a) {
+  a.x = X();
+}
diff --git a/test/SemaObjCXX/propert-dot-error.mm b/test/SemaObjCXX/propert-dot-error.mm
new file mode 100644
index 0000000000..3113e17283
--- /dev/null
+++ b/test/SemaObjCXX/propert-dot-error.mm
@@ -0,0 +1,21 @@
+// RUN: %clang_cc1 -fsyntax-only -verify %s
+// rdar: // 8379892
+
+struct X {
+  X();
+  X(const X&);
+  ~X();
+};
+
+@interface A {
+  X xval;
+}
+
+- (X)x;
+- (void)setx:(X)x;
+@end
+
+void f(A* a) {
+  a.x = X(); // expected-error {{setter method is needed to assign to object using property assignment syntax}}
+}
+
-- 
2.40.0