[PATCH] libstdc++: testsuite: adjust name_fortify test for pre-defined _FORTIFY_SOURCE

[Sam James]

Otherwise we get failures with toolchains that have _FORTIFY_SOURCE
defined already to a different value like 3.

libstdc++-v3/ChangeLog:

	* testsuite/17_intro/names_fortify.cc: Undefine _FORTIFY_SOURCE.
---
I'll commit later if no objections.

 libstdc++-v3/testsuite/17_intro/names_fortify.cc | 1 +
 1 file changed, 1 insertion(+)

diff --git a/libstdc++-v3/testsuite/17_intro/names_fortify.cc b/libstdc++-v3/testsuite/17_intro/names_fortify.cc
index c975412074be..f24af21f8a70 100644
--- a/libstdc++-v3/testsuite/17_intro/names_fortify.cc
+++ b/libstdc++-v3/testsuite/17_intro/names_fortify.cc
@@ -1,6 +1,7 @@
 // { dg-do compile { target *-*-linux* } }
 // { dg-add-options no_pch }
 
+#undef _FORTIFY_SOURCE
 #define _FORTIFY_SOURCE 2
 // Now we can define the macros to poison uses of non-reserved names:
 #include "names.cc"
-- 
2.47.0