Fix uninitialized variable in assert_perror (bug 22761)

ChangeLog

@@ -1,3 +1,9 @@
+2018-02-05  Andreas Schwab  <schwab@suse.de>
+
+	[BZ #22761]
+	* assert/assert-perr.c (__assert_perror_fail): Append %n to format
+	string.
+
 2018-02-04  Samuel Thibault  <samuel.thibault@ens-lyon.org>
 
 	* stdlib/test-atexit-race-common.c [!defined PTHREAD_STACK_MIN]: Do

assert/assert-perr.c

@@ -32,7 +32,7 @@ __assert_perror_fail (int errnum,
   char errbuf[1024];
 
   char *e = __strerror_r (errnum, errbuf, sizeof errbuf);
-  __assert_fail_base (_("%s%s%s:%u: %s%sUnexpected error: %s.\n"),
+  __assert_fail_base (_("%s%s%s:%u: %s%sUnexpected error: %s.\n%n"),
 		      e, file, line, function);
 }
 libc_hidden_def (__assert_perror_fail)