[FYI/PUSHED] Suppress the "unused function" warning for select_strerror_r

[Christian Biesinger via gdb-patches]

We only ever use one of the two overloads, so to avoid breaking -Werror
builds, supress the warning.

gdb/ChangeLog:

2019-12-10  Christian Biesinger  <cbiesinger@google.com>

	* gdbsupport/safe-strerror.c: Supress the unused function warning
	for select_strerror_r.

Change-Id: I344869a382bb36fe181b5b2a31838d1d20f58169
---
 gdb/gdbsupport/safe-strerror.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/gdb/gdbsupport/safe-strerror.c b/gdb/gdbsupport/safe-strerror.c
index 7425af590f..9973fa6785 100644
--- a/gdb/gdbsupport/safe-strerror.c
+++ b/gdb/gdbsupport/safe-strerror.c
@@ -18,6 +18,7 @@
    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #include "common-defs.h"
+#include "diagnostics.h"
 #include <string.h>
 
 /* There are two different versions of strerror_r; one is GNU-specific, the
@@ -26,6 +27,11 @@
    to solve this for us because IPA does not use Gnulib but uses this
    function.  */
 
+/* We only ever use one of the two overloads, so suppress the warning for
+   an unused function.  */
+DIAGNOSTIC_PUSH
+DIAGNOSTIC_IGNORE_UNUSED_FUNCTION
+
 /* Called if we have a XSI-compliant strerror_r.  */
 static char *
 select_strerror_r (int res, char *buf)
@@ -40,6 +46,8 @@ select_strerror_r (char *res, char *)
   return res;
 }
 
+DIAGNOSTIC_POP
+
 /* Implementation of safe_strerror as defined in common-utils.h.  */
 
 const char *
-- 
2.24.0.525.g8f36a354ae-goog