libstdc++: Fix test that uses C++17 variable template in C++14

This test fails if run with -std=gnu++14 because it should be using
is_convertible instead of is_convertible_v.

libstdc++-v3/ChangeLog:

	* testsuite/experimental/propagate_const/observers/107525.cc:
	Use type trait instead of C++17 variable template.

diff --git a/libstdc++-v3/testsuite/experimental/propagate_const/observers/107525.cc b/libstdc++-v3/testsuite/experimental/propagate_const/observers/107525.cc
index e7ecff73c1ae7fea8c6044ce3bc2ce7909e0026f..37e970c3af45e6e36abeba793328fc4d3ce7233f 100644 (file)
--- a/libstdc++-v3/testsuite/experimental/propagate_const/observers/107525.cc
+++ b/libstdc++-v3/testsuite/experimental/propagate_const/observers/107525.cc
@@ -32,10 +32,10 @@ test_const_conversion()
     operator const int*() const = delete;
   };
 
-  static_assert(!std::is_convertible_v<const X, const int*>,
+  static_assert(!std::is_convertible<const X, const int*>::value,
                "Cannot convert const X to const int*");
   // So should not be able to convert const propagate_const<X> to const int*.
-  static_assert(!std::is_convertible_v<const propagate_const<X>, const int*>,
+  static_assert(!std::is_convertible<const propagate_const<X>, const int*>::value,
                "So should not be able to convert const propagate_const<X> to "
                "const int* (although this is not what LFTSv3 says)");
 }