Fix libstdc++ reserved names test to pass on AIX

	* testsuite/17_intro/names.cc: Undefine macros that clash with
	identifiers in AIX system headers.

From-SVN: r246037

libstdc++-v3/ChangeLog

 2017-03-10  Jonathan Wakely  <jwakely@redhat.com>
 
+	* testsuite/17_intro/names.cc: Undefine macros that clash with
+	identifiers in AIX system headers.
+
 	* include/bits/invoke.h (__invoke): Use __invoke_result instead of
 	result_of, and __is_nothrow_invocable instead of
 	__is_nothrow_callable.

libstdc++-v3/testsuite/17_intro/names.cc

@@ -98,4 +98,13 @@
 #define x (
 #define y (
 #define z (
+
+#ifdef _AIX
+// See https://gcc.gnu.org/ml/libstdc++/2017-03/msg00015.html
+#undef f
+#undef r
+#undef x
+#undef y
+#endif
+
 #include <bits/stdc++.h>