commit 6850fafd27ba804d4d4ca8af404beed5574e3749
author Richard Smith <richard-llvm@metafoo.co.uk> Sun Apr 29 08:24:44 2012 +0000
committer Richard Smith <richard-llvm@metafoo.co.uk> Sun Apr 29 08:24:44 2012 +0000
tree 2ba9aa54501f863dc19b7e2ea65999461c1f3aeb
parent e531001b7e44bee5c4ec0be93efbc75adb37a0e3

PR9546, DR1268: A prvalue cannot be reinterpret_cast to an rvalue reference
type. But a glvalue can be reinterpret_cast to either flavor of reference.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@155789 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Sema/SemaCast.cpp

diff --git a/lib/Sema/SemaCast.cpp b/lib/Sema/SemaCast.cpp
index 54683e1..a67d1de 100644
--- a/lib/Sema/SemaCast.cpp
+++ b/lib/Sema/SemaCast.cpp
@@ -1504,10 +1504,9 @@
   }
 
   if (const ReferenceType *DestTypeTmp = DestType->getAs<ReferenceType>()) {
-    bool LValue = DestTypeTmp->isLValueReferenceType();
-    if (LValue && !SrcExpr.get()->isLValue()) {
-      // Cannot cast non-lvalue to lvalue reference type. See the similar 
-      // comment in const_cast.
+    if (!SrcExpr.get()->isGLValue()) {
+      // Cannot cast non-glvalue to (lvalue or rvalue) reference type. See the
+      // similar comment in const_cast.
       msg = diag::err_bad_cxx_cast_rvalue;
       return TC_NotApplicable;
     }

test/CXX/expr/expr.post/expr.reinterpret.cast/p1-0x.cpp

diff --git a/test/CXX/expr/expr.post/expr.reinterpret.cast/p1-0x.cpp b/test/CXX/expr/expr.post/expr.reinterpret.cast/p1-0x.cpp
index 22892a6..212adc8 100644
--- a/test/CXX/expr/expr.post/expr.reinterpret.cast/p1-0x.cpp
+++ b/test/CXX/expr/expr.post/expr.reinterpret.cast/p1-0x.cpp
@@ -10,7 +10,10 @@
 void test_classification(char *ptr) {
   int (&fr0)(int) = reinterpret_cast<int (&&)(int)>(f);
   int &&ir0 = reinterpret_cast<int &&>(*ptr);
-  int &&ir1 = reinterpret_cast<int &&>(0);
-  int &&ir2 = reinterpret_cast<int &&>('a');
+  int &&ir1 = reinterpret_cast<int &&>(0); // expected-error {{rvalue to reference type}}
+  int &&ir2 = reinterpret_cast<int &&>('a'); // expected-error {{rvalue to reference type}}
   int &&ir3 = reinterpret_cast<int &&>(xvalue<char>());
+  // Per DR1268, reinterpret_cast can convert between lvalues and xvalues.
+  int &ir4 = reinterpret_cast<int &>(xvalue<char>());
+  int &&ir5 = reinterpret_cast<int &&>(*ptr);
 }