diff --git a/ap/libc/glibc/glibc-2.23/posix/bug-regex12.c b/ap/libc/glibc/glibc-2.23/posix/bug-regex12.c
new file mode 100644
index 0000000..44a3848
--- /dev/null
+++ b/ap/libc/glibc/glibc-2.23/posix/bug-regex12.c
@@ -0,0 +1,72 @@
+/* Regular expression tests.
+   Copyright (C) 2002-2016 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Jakub Jelinek <jakub@redhat.com>, 2002.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <sys/types.h>
+#include <mcheck.h>
+#include <regex.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+/* Tests supposed to not match.  */
+struct
+{
+  const char *pattern;
+  const char *string;
+  int flags, nmatch;
+} tests[] = {
+  { "^<\\([^~]*\\)\\([^~]\\)[^~]*~\\1\\(.\\).*|=.*\\3.*\\2",
+    "<,.8~2,~so-|=-~.0,123456789<><", REG_NOSUB, 0 },
+  /* In ERE, all carets must be treated as anchors.  */
+  { "a^b", "a^b", REG_EXTENDED, 0 }
+};
+
+int
+main (void)
+{
+  regex_t re;
+  regmatch_t rm[4];
+  size_t i;
+  int n, ret = 0;
+
+  mtrace ();
+
+  for (i = 0; i < sizeof (tests) / sizeof (tests[0]); ++i)
+    {
+      n = regcomp (&re, tests[i].pattern, tests[i].flags);
+      if (n != 0)
+	{
+	  char buf[500];
+	  regerror (n, &re, buf, sizeof (buf));
+	  printf ("regcomp %zd failed: %s\n", i, buf);
+	  ret = 1;
+	  continue;
+	}
+
+      if (! regexec (&re, tests[i].string, tests[i].nmatch,
+		     tests[i].nmatch ? rm : NULL, 0))
+	{
+	  printf ("regexec %zd incorrectly matched\n", i);
+	  ret = 1;
+	}
+
+      regfree (&re);
+    }
+
+  return ret;
+}