Mark the test using <experimental/memory_resource> to require c++experimental.
When built against the old libc++ version the test was causing linker error
Undefined symbols for architecture x86_64:
"std::experimental::fundamentals_v1::pmr::new_delete_resource()", referenced from:
void test_evil<WidgetV0, WidgetV0>() in construct_piecewise_pair_evil.pass.cpp.o
void test_evil<WidgetV0, WidgetV1>() in construct_piecewise_pair_evil.pass.cpp.o
void test_evil<WidgetV0, WidgetV2>() in construct_piecewise_pair_evil.pass.cpp.o
void test_evil<WidgetV0, WidgetV3>() in construct_piecewise_pair_evil.pass.cpp.o
void test_evil<WidgetV1, WidgetV0>() in construct_piecewise_pair_evil.pass.cpp.o
void test_evil<WidgetV1, WidgetV1>() in construct_piecewise_pair_evil.pass.cpp.o
void test_evil<WidgetV1, WidgetV2>() in construct_piecewise_pair_evil.pass.cpp.o
...
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@334431 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_piecewise_pair_evil.pass.cpp b/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_piecewise_pair_evil.pass.cpp
index f087ec2..7dc8f3a 100644
--- a/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_piecewise_pair_evil.pass.cpp
+++ b/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_piecewise_pair_evil.pass.cpp
@@ -7,6 +7,7 @@
//
//===----------------------------------------------------------------------===//
+// REQUIRES: c++experimental
// UNSUPPORTED: c++98, c++03
// <memory_resource>
