From: Douglas Gregor <dgregor@apple.com>
Date: Tue, 8 Feb 2011 02:14:35 +0000 (+0000)
Subject: Sema::MaybeBindToTemporary() shouldn't treat any expression returning
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=5e6fcd4ba9cc4cab5a6be0a76bca9d51480ea346;p=clang

Sema::MaybeBindToTemporary() shouldn't treat any expression returning
a glvalue as a temporary. Previously, we were enumerating all of the
cases that coul return glvalues and might be called with
Sema::MaybeBindToTemporary(), but that was gross and we missed the
Objective-C property reference case.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@125070 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Sema/SemaExprCXX.cpp b/lib/Sema/SemaExprCXX.cpp
index 81031a54ee..ea1ad51e9d 100644
--- a/lib/Sema/SemaExprCXX.cpp
+++ b/lib/Sema/SemaExprCXX.cpp
@@ -3370,17 +3370,9 @@ ExprResult Sema::MaybeBindToTemporary(Expr *E) {
   if (!RT)
     return Owned(E);
 
-  // If this is the result of a call or an Objective-C message send expression,
-  // our source might actually be a reference, in which case we shouldn't bind.
-  if (CallExpr *CE = dyn_cast<CallExpr>(E)) {
-    if (CE->getCallReturnType()->isReferenceType())
-      return Owned(E);
-  } else if (ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(E)) {
-    if (const ObjCMethodDecl *MD = ME->getMethodDecl()) {
-      if (MD->getResultType()->isReferenceType())
-        return Owned(E);
-    }
-  }
+  // If the result is a glvalue, we shouldn't bind it.
+  if (E->Classify(Context).isGLValue())
+    return Owned(E);
 
   // That should be enough to guarantee that this type is complete.
   // If it has a trivial destructor, we can avoid the extra copy.
diff --git a/test/SemaObjCXX/properties.mm b/test/SemaObjCXX/properties.mm
new file mode 100644
index 0000000000..f148b3395d
--- /dev/null
+++ b/test/SemaObjCXX/properties.mm
@@ -0,0 +1,24 @@
+// RUN: %clang_cc1 -fsyntax-only -verify %s
+
+struct X { 
+  void f() const;
+  ~X();
+};
+
+@interface A {
+  X x_;
+}
+
+- (const X&)x;
+- (void)setx:(const X&)other;
+@end
+
+@implementation A
+
+- (const X&)x { return x_; }
+- (void)setx:(const X&)other { x_ = other; }
+- (void)method {
+  self.x.f();
+} 
+@end
+