Workaround GCC bug PR78489 - SFINAE order is not respected.

This patch works around variant test failures which are new to
GCC 8. GCC 8 either doesn't perform SFINAE in lexical order, or
it doesn't halt after encountering the first failure. This
causes hard error to occur instead of substitution failure.

See gcc.gnu.org/PR78489

llvm-svn: 328261

1 files changed, 6 insertions, 0 deletions

diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/in_place_index_init_list_args.pass.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/in_place_index_init_list_args.pass.cpp
index 608cdf9d6ef..9d0bf55fb53 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/in_place_index_init_list_args.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/in_place_index_init_list_args.pass.cpp
@@ -73,6 +73,12 @@ void test_ctor_sfinae() {
         !std::is_constructible<V, std::in_place_index_t<2>, IL>::value, "");
     static_assert(!test_convertible<V, std::in_place_index_t<2>, IL>(), "");
   }
+  { // index not in variant
+    using V = std::variant<InitList, InitListArg, int>;
+    static_assert(
+        !std::is_constructible<V, std::in_place_index_t<3>, IL>::value, "");
+    static_assert(!test_convertible<V, std::in_place_index_t<3>, IL>(), "");
+  }
 }
 
 void test_ctor_basic() {