diff --git a/ChangeLog b/ChangeLog
index de2e7ccbbd..59d95d166f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2014-12-11  Roland McGrath  <roland@hack.frob.com>
+
+	* posix/regexbug1.c (main): Use "%s" format with regerror results,
+	rather than assuming they won't contain any '%'s.
+
 2014-12-11  Chris Metcalf  <cmetcalf@ezchip.com>
 
 	* sysdeps/tile/tilegx/memset.c (__memcpy): Add
diff --git a/posix/regexbug1.c b/posix/regexbug1.c
index 28640968d0..17643e7e4d 100644
--- a/posix/regexbug1.c
+++ b/posix/regexbug1.c
@@ -18,7 +18,7 @@ main (void)
     {
       char buf[100];
       regerror (reerr, &re, buf, sizeof buf);
-      error (EXIT_FAILURE, 0, buf);
+      error (EXIT_FAILURE, 0, "%s", buf);
     }
 
   if (regexec (&re, "002", 2, ma, 0) != 0)
@@ -35,7 +35,7 @@ main (void)
     {
       char buf[100];
       regerror (reerr, &re, buf, sizeof buf);
-      error (EXIT_FAILURE, 0, buf);
+      error (EXIT_FAILURE, 0, "%s", buf);
     }
 
   if (regexec (&re, "002", 2, ma, 0) != 0)