[committed] libstdc++: Add tests for std::invoke feature test macro

[Jonathan Wakely via Gcc-patches]

libstdc++-v3/ChangeLog:

        * testsuite/20_util/function_objects/invoke/3.cc: Check feature
        test macro.
        * testsuite/20_util/function_objects/invoke/version.cc: New test.

Tested powerpc64le-linux. Committed to trunk.


commit 29745bf06276b9628d08ef1c9e28890cc56df4aa
Author: Jonathan Wakely <jwak...@redhat.com>
Date:   Wed May 5 12:41:14 2021

    libstdc++: Add tests for std::invoke feature test macro
    
    libstdc++-v3/ChangeLog:
    
            * testsuite/20_util/function_objects/invoke/3.cc: Check feature
            test macro.
            * testsuite/20_util/function_objects/invoke/version.cc: New test.

diff --git a/libstdc++-v3/testsuite/20_util/function_objects/invoke/3.cc 
b/libstdc++-v3/testsuite/20_util/function_objects/invoke/3.cc
index 5ffc5dedbab..40e068e86fd 100644
--- a/libstdc++-v3/testsuite/20_util/function_objects/invoke/3.cc
+++ b/libstdc++-v3/testsuite/20_util/function_objects/invoke/3.cc
@@ -15,11 +15,16 @@
 // with this library; see the file COPYING3.  If not see
 // <http://www.gnu.org/licenses/>.
 
-// { dg-options "-std=gnu++17" }
 // { dg-do compile { target c++17 } }
 
 #include <functional>
 
+#ifndef __cpp_lib_invoke
+# error Feature-test macro for invoke is missing in <functional>
+#elif __cpp_lib_invoke < 201411L
+# error Feature-test macro for invoke has the wrong value in <functional>
+#endif
+
 struct abstract {
   virtual ~abstract() = 0;
   void operator()() noexcept;
diff --git a/libstdc++-v3/testsuite/20_util/function_objects/invoke/version.cc 
b/libstdc++-v3/testsuite/20_util/function_objects/invoke/version.cc
new file mode 100644
index 00000000000..cf1a46a1ada
--- /dev/null
+++ b/libstdc++-v3/testsuite/20_util/function_objects/invoke/version.cc
@@ -0,0 +1,9 @@
+// { dg-do compile { target c++17 } }
+
+#include <version>
+
+#ifndef __cpp_lib_invoke
+# error Feature-test macro for invoke is missing in <version>
+#elif __cpp_lib_invoke < 201411L
+# error Feature-test macro for invoke has the wrong value in <version>
+#endif