diff --git a/ap/libc/glibc/glibc-2.23/posix/bug-regex18.c b/ap/libc/glibc/glibc-2.23/posix/bug-regex18.c
new file mode 100644
index 0000000..6902f52
--- /dev/null
+++ b/ap/libc/glibc/glibc-2.23/posix/bug-regex18.c
@@ -0,0 +1,99 @@
+/* Turkish 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>
+#include <locale.h>
+
+/* Tests supposed to match.  */
+struct
+{
+  const char *pattern;
+  const char *string;
+  int flags, nmatch;
+  regmatch_t rm[5];
+} tests[] = {
+  /* \xc4\xb0		LATIN CAPITAL LETTER I WITH DOT ABOVE
+     \xc4\xb1		LATIN SMALL LETTER DOTLESS I
+     \xe2\x80\x94	EM DASH  */
+  { "\xc4\xb0I*\xc4\xb1$", "aBi\xc4\xb1\xc4\xb1I", REG_ICASE, 2,
+    { { 2, 8 }, { -1, -1 } } },
+  { "[\xc4\xb0x]I*\xc4\xb1$", "aBi\xc4\xb1\xc4\xb1I", REG_ICASE, 2,
+    { { 2, 8 }, { -1, -1 } } },
+  { "[^x]I*\xc4\xb1$", "aBi\xc4\xb1\xc4\xb1I", REG_ICASE, 2,
+    { { 2, 8 }, { -1, -1 } } },
+  { "([[:alpha:]]i[[:xdigit:]])(\xc4\xb1*)(\xc4\xb0{2})",
+    "\xe2\x80\x94\xc4\xb1\xc4\xb0""fIi\xc4\xb0ii", REG_ICASE | REG_EXTENDED,
+    4, { { 3, 12 }, { 3, 8 }, { 8, 9 }, { 9, 12 } } },
+  { "\xc4\xb1i(i)*()(\\s\xc4\xb0|\\SI)", "SIi\xc4\xb0\xc4\xb0 is",
+    REG_ICASE | REG_EXTENDED, 4, { { 1, 9 }, { 5, 7 }, { 7, 7 }, { 7, 9 } } },
+  { "\xc4\xb1i(i)*()(\\s\xc4\xb0|\\SI)", "\xc4\xb1\xc4\xb0\xc4\xb0iJ\xc4\xb1",
+    REG_ICASE | REG_EXTENDED, 4,
+    { { 0, 10 }, { 6, 7 }, { 7, 7 }, { 7, 10 } } },
+};
+
+int
+main (void)
+{
+  regex_t re;
+  regmatch_t rm[5];
+  size_t i;
+  int n, ret = 0;
+
+  setlocale (LC_ALL, "tr_TR.UTF-8");
+  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, rm, 0))
+	{
+	  printf ("regexec %zd failed\n", i);
+	  ret = 1;
+	  regfree (&re);
+	  continue;
+	}
+
+      for (n = 0; n < tests[i].nmatch; ++n)
+	if (rm[n].rm_so != tests[i].rm[n].rm_so
+              || rm[n].rm_eo != tests[i].rm[n].rm_eo)
+	  {
+	    if (tests[i].rm[n].rm_so == -1 && tests[i].rm[n].rm_eo == -1)
+	      break;
+	    printf ("regexec match failure rm[%d] %d..%d\n",
+		    n, rm[n].rm_so, rm[n].rm_eo);
+	    ret = 1;
+	    break;
+	  }
+
+      regfree (&re);
+    }
+
+  return ret;
+}