libstc++: Add dg-error for additional error in C++11 mode

When the comparison with a nullptr_t is ill-formed, there is an
additional error for C++11 mode due to the constexpr function body being
invalid.

Signed-off-by: Jonathan Wakely <jwakely@redhat.com>
libstdc++-v3/ChangeLog:

	* testsuite/20_util/tuple/comparison_operators/overloaded2.cc:
	Add dg-error for c++11_only target.

diff --git a/libstdc++-v3/testsuite/20_util/tuple/comparison_operators/overloaded2.cc b/libstdc++-v3/testsuite/20_util/tuple/comparison_operators/overloaded2.cc
index fc3118f..a66a931 100644 (file)
--- a/libstdc++-v3/testsuite/20_util/tuple/comparison_operators/overloaded2.cc
+++ b/libstdc++-v3/testsuite/20_util/tuple/comparison_operators/overloaded2.cc
@@ -50,3 +50,4 @@ auto a = std::make_tuple(nullptr, Compares{}, 2, 'U');
 auto b = a < a;
 
 // { dg-error "ordered comparison" "" { target *-*-* } 0 }
+// { dg-error "not a return-statement" "" { target c++11_only } 0 }