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diff --git a/gcc-4.7/libiberty/memmem.c b/gcc-4.7/libiberty/memmem.c
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+/* Copyright (C) 1991,92,93,94,96,97,98,2000,2004,2007,2011 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program 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 General Public License for more details.
+
+ You should have received a copy of the GNU General Public License along
+ with this program; if not, write to the Free Software Foundation,
+ Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
+
+/*
+
+@deftypefn Supplemental void* memmem (const void *@var{haystack}, @
+ size_t @var{haystack_len} const void *@var{needle}, size_t @var{needle_len})
+
+Returns a pointer to the first occurrence of @var{needle} (length
+@var{needle_len}) in @var{haystack} (length @var{haystack_len}).
+Returns @code{NULL} if not found.
+
+@end deftypefn
+
+*/
+
+#ifndef _LIBC
+# include <config.h>
+#endif
+
+#include <stddef.h>
+#include <string.h>
+
+#ifndef _LIBC
+# define __builtin_expect(expr, val) (expr)
+#endif
+
+#undef memmem
+
+/* Return the first occurrence of NEEDLE in HAYSTACK. */
+void *
+memmem (const void *haystack, size_t haystack_len, const void *needle,
+ size_t needle_len)
+{
+ const char *begin;
+ const char *const last_possible
+ = (const char *) haystack + haystack_len - needle_len;
+
+ if (needle_len == 0)
+ /* The first occurrence of the empty string is deemed to occur at
+ the beginning of the string. */
+ return (void *) haystack;
+
+ /* Sanity check, otherwise the loop might search through the whole
+ memory. */
+ if (__builtin_expect (haystack_len < needle_len, 0))
+ return NULL;
+
+ for (begin = (const char *) haystack; begin <= last_possible; ++begin)
+ if (begin[0] == ((const char *) needle)[0] &&
+ !memcmp ((const void *) &begin[1],
+ (const void *) ((const char *) needle + 1),
+ needle_len - 1))
+ return (void *) begin;
+
+ return NULL;
+}