Permit the ssl locking callback to be unused

Sufficiently modern ssl does not need a locking callback so
crypto_set_locking_cb is a no-op.  That leads to the locking callback
being an unused static function.  Let gcc know this is OK.

1 files changed, 3 insertions, 2 deletions

diff --git a/tls.c b/tls.c
index ba3cab5..7b33d8e 100644
--- a/tls.c
+++ b/tls.c
@@ -7,6 +7,7 @@
 
 #include <stdlib.h>
 #include <unistd.h>
+#include <string.h>
 #include <assert.h>
 #include <fcntl.h>
 #include <limits.h>
@@ -194,8 +195,8 @@ static pthread_mutex_t *s_openssl_mutexes = NULL;
 static int s_openssl_mutexes_count = 0;
 
 /** Callback for OpenSSL when a lock is to be held or released. */
-static void
-openssl_locking_cb_ (int mode, int i, const char *file, int line)
+__attribute__((unused)) static void
+openssl_locking_cb_ (int mode, int i, const char *file, int line) 
 {
   if (s_openssl_mutexes == NULL || i >= s_openssl_mutexes_count)
     return;