A smaller, kinder, gentler regexp implementation.

1 files changed, 5725 insertions, 0 deletions

diff --git a/libc/misc/regex/regex.c b/libc/misc/regex/regex.c
new file mode 100644
index 000000000..64e754ee0
--- /dev/null
+++ b/libc/misc/regex/regex.c
@@ -0,0 +1,5725 @@
+/* Extended regular expression matching and search library,
+   version 0.12.
+   (Implements POSIX draft P1003.2/D11.2, except for some of the
+   internationalization features.)
+   Copyright (C) 1993-1999, 2000 Free Software Foundation, Inc.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+/* AIX requires this to be the first thing in the file. */
+#if defined _AIX && !defined REGEX_MALLOC
+#pragma alloca
+#endif
+
+#undef	_GNU_SOURCE
+#define _GNU_SOURCE
+#define STDC_HEADERS
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#ifndef PARAMS
+# if defined __GNUC__ || (defined __STDC__ && __STDC__)
+#  define PARAMS(args) args
+# else
+#  define PARAMS(args) ()
+# endif							/* GCC.  */
+#endif							/* Not PARAMS.  */
+
+#if defined STDC_HEADERS && !defined emacs
+# include <stddef.h>
+#else
+/* We need this for `regex.h', and perhaps for the Emacs include files.  */
+# include <sys/types.h>
+#endif
+
+#define WIDE_CHAR_SUPPORT (HAVE_WCTYPE_H && HAVE_WCHAR_H && HAVE_BTOWC)
+
+/* For platform which support the ISO C amendement 1 functionality we
+   support user defined character classes.  */
+#if defined _LIBC || WIDE_CHAR_SUPPORT
+/* Solaris 2.5 has a bug: <wchar.h> must be included before <wctype.h>.  */
+# include <wchar.h>
+# include <wctype.h>
+#endif
+
+#ifdef _LIBC
+/* We have to keep the namespace clean.  */
+# define regfree(preg) __regfree (preg)
+# define regexec(pr, st, nm, pm, ef) __regexec (pr, st, nm, pm, ef)
+# define regcomp(preg, pattern, cflags) __regcomp (preg, pattern, cflags)
+# define regerror(errcode, preg, errbuf, errbuf_size) \
+	__regerror(errcode, preg, errbuf, errbuf_size)
+# define re_set_registers(bu, re, nu, st, en) \
+	__re_set_registers (bu, re, nu, st, en)
+# define re_match_2(bufp, string1, size1, string2, size2, pos, regs, stop) \
+	__re_match_2 (bufp, string1, size1, string2, size2, pos, regs, stop)
+# define re_match(bufp, string, size, pos, regs) \
+	__re_match (bufp, string, size, pos, regs)
+# define re_search(bufp, string, size, startpos, range, regs) \
+	__re_search (bufp, string, size, startpos, range, regs)
+# define re_compile_pattern(pattern, length, bufp) \
+	__re_compile_pattern (pattern, length, bufp)
+# define re_set_syntax(syntax) __re_set_syntax (syntax)
+# define re_search_2(bufp, st1, s1, st2, s2, startpos, range, regs, stop) \
+	__re_search_2 (bufp, st1, s1, st2, s2, startpos, range, regs, stop)
+# define re_compile_fastmap(bufp) __re_compile_fastmap (bufp)
+
+#define btowc __btowc
+#endif
+
+/* This is for other GNU distributions with internationalized messages.  */
+#if HAVE_LIBINTL_H || defined _LIBC
+# include <libintl.h>
+#else
+# define gettext(msgid) (msgid)
+#endif
+
+#ifndef gettext_noop
+/* This define is so xgettext can find the internationalizable
+   strings.  */
+# define gettext_noop(String) String
+#endif
+
+/* The `emacs' switch turns on certain matching commands
+   that make sense only in Emacs. */
+#ifdef emacs
+
+# include "lisp.h"
+# include "buffer.h"
+# include "syntax.h"
+
+#else							/* not emacs */
+
+/* If we are not linking with Emacs proper,
+   we can't use the relocating allocator
+   even if config.h says that we can.  */
+# undef REL_ALLOC
+
+# if defined STDC_HEADERS || defined _LIBC
+#  include <stdlib.h>
+# else
+char *malloc();
+char *realloc();
+# endif
+
+/* When used in Emacs's lib-src, we need to get bzero and bcopy somehow.
+   If nothing else has been done, use the method below.  */
+# ifdef INHIBIT_STRING_HEADER
+#  if !(defined HAVE_BZERO && defined HAVE_BCOPY)
+#   if !defined bzero && !defined bcopy
+#    undef INHIBIT_STRING_HEADER
+#   endif
+#  endif
+# endif
+
+/* This is the normal way of making sure we have a bcopy and a bzero.
+   This is used in most programs--a few other programs avoid this
+   by defining INHIBIT_STRING_HEADER.  */
+# ifndef INHIBIT_STRING_HEADER
+#  if defined HAVE_STRING_H || defined STDC_HEADERS || defined _LIBC
+#   include <string.h>
+#   ifndef bzero
+#    ifndef _LIBC
+#     define bzero(s, n)	(memset (s, '\0', n), (s))
+#    else
+#     define bzero(s, n)	__bzero (s, n)
+#    endif
+#   endif
+#  else
+#   include <strings.h>
+#   ifndef memcmp
+#    define memcmp(s1, s2, n)	bcmp (s1, s2, n)
+#   endif
+#   ifndef memcpy
+#    define memcpy(d, s, n)	(bcopy (s, d, n), (d))
+#   endif
+#  endif
+# endif
+
+/* Define the syntax stuff for \<, \>, etc.  */
+
+/* This must be nonzero for the wordchar and notwordchar pattern
+   commands in re_match_2.  */
+# ifndef Sword
+#  define Sword 1
+# endif
+
+# ifdef SWITCH_ENUM_BUG
+#  define SWITCH_ENUM_CAST(x) ((int)(x))
+# else
+#  define SWITCH_ENUM_CAST(x) (x)
+# endif
+
+#endif							/* not emacs */
+
+/* Get the interface, including the syntax bits.  */
+#include <regex.h>
+
+/* isalpha etc. are used for the character classes.  */
+#include <ctype.h>
+
+/* Jim Meyering writes:
+
+   "... Some ctype macros are valid only for character codes that
+   isascii says are ASCII (SGI's IRIX-4.0.5 is one such system --when
+   using /bin/cc or gcc but without giving an ansi option).  So, all
+   ctype uses should be through macros like ISPRINT...  If
+   STDC_HEADERS is defined, then autoconf has verified that the ctype
+   macros don't need to be guarded with references to isascii. ...
+   Defining isascii to 1 should let any compiler worth its salt
+   eliminate the && through constant folding."
+   Solaris defines some of these symbols so we must undefine them first.  */
+
+#undef ISASCII
+#if defined STDC_HEADERS || (!defined isascii && !defined HAVE_ISASCII)
+# define ISASCII(c) 1
+#else
+# define ISASCII(c) isascii(c)
+#endif
+
+#ifdef isblank
+# define ISBLANK(c) (ISASCII (c) && isblank (c))
+#else
+# define ISBLANK(c) ((c) == ' ' || (c) == '\t')
+#endif
+#ifdef isgraph
+# define ISGRAPH(c) (ISASCII (c) && isgraph (c))
+#else
+# define ISGRAPH(c) (ISASCII (c) && isprint (c) && !isspace (c))
+#endif
+
+#undef ISPRINT
+#define ISPRINT(c) (ISASCII (c) && isprint (c))
+#define ISDIGIT(c) (ISASCII (c) && isdigit (c))
+#define ISALNUM(c) (ISASCII (c) && isalnum (c))
+#define ISALPHA(c) (ISASCII (c) && isalpha (c))
+#define ISCNTRL(c) (ISASCII (c) && iscntrl (c))
+#define ISLOWER(c) (ISASCII (c) && islower (c))
+#define ISPUNCT(c) (ISASCII (c) && ispunct (c))
+#define ISSPACE(c) (ISASCII (c) && isspace (c))
+#define ISUPPER(c) (ISASCII (c) && isupper (c))
+#define ISXDIGIT(c) (ISASCII (c) && isxdigit (c))
+
+#ifdef _tolower
+# define TOLOWER(c) _tolower(c)
+#else
+# define TOLOWER(c) tolower(c)
+#endif
+
+#ifndef NULL
+# define NULL (void *)0
+#endif
+
+/* We remove any previous definition of `SIGN_EXTEND_CHAR',
+   since ours (we hope) works properly with all combinations of
+   machines, compilers, `char' and `unsigned char' argument types.
+   (Per Bothner suggested the basic approach.)  */
+#undef SIGN_EXTEND_CHAR
+#if __STDC__
+# define SIGN_EXTEND_CHAR(c) ((signed char) (c))
+#else							/* not __STDC__ */
+/* As in Harbison and Steele.  */
+# define SIGN_EXTEND_CHAR(c) ((((unsigned char) (c)) ^ 128) - 128)
+#endif
+
+#ifndef emacs
+/* How many characters in the character set.  */
+# define CHAR_SET_SIZE 256
+
+# ifdef SYNTAX_TABLE
+
+extern char *re_syntax_table;
+
+# else							/* not SYNTAX_TABLE */
+
+static char re_syntax_table[CHAR_SET_SIZE];
+
+static void init_syntax_once()
+{
+	register int c;
+	static int done = 0;
+
+	if (done)
+		return;
+	bzero(re_syntax_table, sizeof re_syntax_table);
+
+	for (c = 0; c < CHAR_SET_SIZE; ++c)
+		if (ISALNUM(c))
+			re_syntax_table[c] = Sword;
+
+	re_syntax_table['_'] = Sword;
+
+	done = 1;
+}
+
+# endif							/* not SYNTAX_TABLE */
+
+# define SYNTAX(c) re_syntax_table[((c) & 0xFF)]
+
+#endif							/* emacs */
+
+/* Should we use malloc or alloca?  If REGEX_MALLOC is not defined, we
+   use `alloca' instead of `malloc'.  This is because using malloc in
+   re_search* or re_match* could cause memory leaks when C-g is used in
+   Emacs; also, malloc is slower and causes storage fragmentation.  On
+   the other hand, malloc is more portable, and easier to debug.
+
+   Because we sometimes use alloca, some routines have to be macros,
+   not functions -- `alloca'-allocated space disappears at the end of the
+   function it is called in.  */
+
+#ifdef REGEX_MALLOC
+
+# define REGEX_ALLOCATE malloc
+# define REGEX_REALLOCATE(source, osize, nsize) realloc (source, nsize)
+# define REGEX_FREE free
+
+#else							/* not REGEX_MALLOC  */
+
+/* Emacs already defines alloca, sometimes.  */
+# ifndef alloca
+
+/* Make alloca work the best possible way.  */
+#  ifdef __GNUC__
+#   define alloca __builtin_alloca
+#  else							/* not __GNUC__ */
+#   if HAVE_ALLOCA_H
+#    include <alloca.h>
+#   endif						/* HAVE_ALLOCA_H */
+#  endif						/* not __GNUC__ */
+
+# endif							/* not alloca */
+
+# define REGEX_ALLOCATE alloca
+
+/* Assumes a `char *destination' variable.  */
+# define REGEX_REALLOCATE(source, osize, nsize)				\
+  (destination = (char *) alloca (nsize),				\
+   memcpy (destination, source, osize))
+
+/* No need to do anything to free, after alloca.  */
+# define REGEX_FREE(arg) ((void)0)	/* Do nothing!  But inhibit gcc warning.  */
+
+#endif							/* not REGEX_MALLOC */
+
+/* Define how to allocate the failure stack.  */
+
+#if defined REL_ALLOC && defined REGEX_MALLOC
+
+# define REGEX_ALLOCATE_STACK(size)				\
+  r_alloc (&failure_stack_ptr, (size))
+# define REGEX_REALLOCATE_STACK(source, osize, nsize)		\
+  r_re_alloc (&failure_stack_ptr, (nsize))
+# define REGEX_FREE_STACK(ptr)					\
+  r_alloc_free (&failure_stack_ptr)
+
+#else							/* not using relocating allocator */
+
+# ifdef REGEX_MALLOC
+
+#  define REGEX_ALLOCATE_STACK malloc
+#  define REGEX_REALLOCATE_STACK(source, osize, nsize) realloc (source, nsize)
+#  define REGEX_FREE_STACK free
+
+# else							/* not REGEX_MALLOC */
+
+#  define REGEX_ALLOCATE_STACK alloca
+
+#  define REGEX_REALLOCATE_STACK(source, osize, nsize)			\
+   REGEX_REALLOCATE (source, osize, nsize)
+/* No need to explicitly free anything.  */
+#  define REGEX_FREE_STACK(arg)
+
+# endif							/* not REGEX_MALLOC */
+#endif							/* not using relocating allocator */
+
+
+/* True if `size1' is non-NULL and PTR is pointing anywhere inside
+   `string1' or just past its end.  This works if PTR is NULL, which is
+   a good thing.  */
+#define FIRST_STRING_P(ptr) 					\
+  (size1 && string1 <= (ptr) && (ptr) <= string1 + size1)
+
+/* (Re)Allocate N items of type T using malloc, or fail.  */
+#define TALLOC(n, t) ((t *) malloc ((n) * sizeof (t)))
+#define RETALLOC(addr, n, t) ((addr) = (t *) realloc (addr, (n) * sizeof (t)))
+#define RETALLOC_IF(addr, n, t) \
+  if (addr) RETALLOC((addr), (n), t); else (addr) = TALLOC ((n), t)
+#define REGEX_TALLOC(n, t) ((t *) REGEX_ALLOCATE ((n) * sizeof (t)))
+
+#define BYTEWIDTH 8				/* In bits.  */
+
+#define STREQ(s1, s2) ((strcmp (s1, s2) == 0))
+
+#undef MAX
+#undef MIN
+#define MAX(a, b) ((a) > (b) ? (a) : (b))
+#define MIN(a, b) ((a) < (b) ? (a) : (b))
+
+typedef char boolean;
+
+#define false 0
+#define true 1
+
+static int re_match_2_internal PARAMS((struct re_pattern_buffer * bufp,
+									   const char *string1, int size1,
+									   const char *string2, int size2,
+									   int pos,
+									   struct re_registers * regs,
+
+									   int stop));
+
+/* These are the command codes that appear in compiled regular
+   expressions.  Some opcodes are followed by argument bytes.  A
+   command code can specify any interpretation whatsoever for its
+   arguments.  Zero bytes may appear in the compiled regular expression.  */
+
+typedef enum {
+	no_op = 0,
+
+	/* Succeed right away--no more backtracking.  */
+	succeed,
+
+	/* Followed by one byte giving n, then by n literal bytes.  */
+	exactn,
+
+	/* Matches any (more or less) character.  */
+	anychar,
+
+	/* Matches any one char belonging to specified set.  First
+	   following byte is number of bitmap bytes.  Then come bytes
+	   for a bitmap saying which chars are in.  Bits in each byte
+	   are ordered low-bit-first.  A character is in the set if its
+	   bit is 1.  A character too large to have a bit in the map is
+	   automatically not in the set.  */
+	charset,
+
+	/* Same parameters as charset, but match any character that is
+	   not one of those specified.  */
+	charset_not,
+
+	/* Start remembering the text that is matched, for storing in a
+	   register.  Followed by one byte with the register number, in
+	   the range 0 to one less than the pattern buffer's re_nsub
+	   field.  Then followed by one byte with the number of groups
+	   inner to this one.  (This last has to be part of the
+	   start_memory only because we need it in the on_failure_jump
+	   of re_match_2.)  */
+	start_memory,
+
+	/* Stop remembering the text that is matched and store it in a
+	   memory register.  Followed by one byte with the register
+	   number, in the range 0 to one less than `re_nsub' in the
+	   pattern buffer, and one byte with the number of inner groups,
+	   just like `start_memory'.  (We need the number of inner
+	   groups here because we don't have any easy way of finding the
+	   corresponding start_memory when we're at a stop_memory.)  */
+	stop_memory,
+
+	/* Match a duplicate of something remembered. Followed by one
+	   byte containing the register number.  */
+	duplicate,
+
+	/* Fail unless at beginning of line.  */
+	begline,
+
+	/* Fail unless at end of line.  */
+	endline,
+
+	/* Succeeds if at beginning of buffer (if emacs) or at beginning
+	   of string to be matched (if not).  */
+	begbuf,
+
+	/* Analogously, for end of buffer/string.  */
+	endbuf,
+
+	/* Followed by two byte relative address to which to jump.  */
+	jump,
+
+	/* Same as jump, but marks the end of an alternative.  */
+	jump_past_alt,
+
+	/* Followed by two-byte relative address of place to resume at
+	   in case of failure.  */
+	on_failure_jump,
+
+	/* Like on_failure_jump, but pushes a placeholder instead of the
+	   current string position when executed.  */
+	on_failure_keep_string_jump,
+
+	/* Throw away latest failure point and then jump to following
+	   two-byte relative address.  */
+	pop_failure_jump,
+
+	/* Change to pop_failure_jump if know won't have to backtrack to
+	   match; otherwise change to jump.  This is used to jump
+	   back to the beginning of a repeat.  If what follows this jump
+	   clearly won't match what the repeat does, such that we can be
+	   sure that there is no use backtracking out of repetitions
+	   already matched, then we change it to a pop_failure_jump.
+	   Followed by two-byte address.  */
+	maybe_pop_jump,
+
+	/* Jump to following two-byte address, and push a dummy failure
+	   point. This failure point will be thrown away if an attempt
+	   is made to use it for a failure.  A `+' construct makes this
+	   before the first repeat.  Also used as an intermediary kind
+	   of jump when compiling an alternative.  */
+	dummy_failure_jump,
+
+	/* Push a dummy failure point and continue.  Used at the end of
+	   alternatives.  */
+	push_dummy_failure,
+
+	/* Followed by two-byte relative address and two-byte number n.
+	   After matching N times, jump to the address upon failure.  */
+	succeed_n,
+
+	/* Followed by two-byte relative address, and two-byte number n.
+	   Jump to the address N times, then fail.  */
+	jump_n,
+
+	/* Set the following two-byte relative address to the
+	   subsequent two-byte number.  The address *includes* the two
+	   bytes of number.  */
+	set_number_at,
+
+	wordchar,					/* Matches any word-constituent character.  */
+	notwordchar,				/* Matches any char that is not a word-constituent.  */
+
+	wordbeg,					/* Succeeds if at word beginning.  */
+	wordend,					/* Succeeds if at word end.  */
+
+	wordbound,					/* Succeeds if at a word boundary.  */
+	notwordbound				/* Succeeds if not at a word boundary.  */
+#ifdef emacs
+		, before_dot,			/* Succeeds if before point.  */
+	at_dot,						/* Succeeds if at point.  */
+	after_dot,					/* Succeeds if after point.  */
+
+	/* Matches any character whose syntax is specified.  Followed by
+	   a byte which contains a syntax code, e.g., Sword.  */
+	syntaxspec,
+
+	/* Matches any character whose syntax is not that specified.  */
+	notsyntaxspec
+#endif							/* emacs */
+} re_opcode_t;
+
+/* Common operations on the compiled pattern.  */
+
+/* Store NUMBER in two contiguous bytes starting at DESTINATION.  */
+
+#define STORE_NUMBER(destination, number)				\
+  do {									\
+    (destination)[0] = (number) & 0377;					\
+    (destination)[1] = (number) >> 8;					\
+  } while (0)
+
+/* Same as STORE_NUMBER, except increment DESTINATION to
+   the byte after where the number is stored.  Therefore, DESTINATION
+   must be an lvalue.  */
+
+#define STORE_NUMBER_AND_INCR(destination, number)			\
+  do {									\
+    STORE_NUMBER (destination, number);					\
+    (destination) += 2;							\
+  } while (0)
+
+/* Put into DESTINATION a number stored in two contiguous bytes starting
+   at SOURCE.  */
+
+#define EXTRACT_NUMBER(destination, source)				\
+  do {									\
+    (destination) = *(source) & 0377;					\
+    (destination) += SIGN_EXTEND_CHAR (*((source) + 1)) << 8;		\
+  } while (0)
+
+#ifdef DEBUG
+static void extract_number _RE_ARGS((int *dest, unsigned char *source));
+static void extract_number(dest, source)
+int *dest;
+unsigned char *source;
+{
+	int temp = SIGN_EXTEND_CHAR(*(source + 1));
+
+	*dest = *source & 0377;
+	*dest += temp << 8;
+}
+
+# ifndef EXTRACT_MACROS			/* To debug the macros.  */
+#  undef EXTRACT_NUMBER
+#  define EXTRACT_NUMBER(dest, src) extract_number (&dest, src)
+# endif							/* not EXTRACT_MACROS */
+
+#endif							/* DEBUG */
+
+/* Same as EXTRACT_NUMBER, except increment SOURCE to after the number.
+   SOURCE must be an lvalue.  */
+
+#define EXTRACT_NUMBER_AND_INCR(destination, source)			\
+  do {									\
+    EXTRACT_NUMBER (destination, source);				\
+    (source) += 2; 							\
+  } while (0)
+
+#ifdef DEBUG
+static void extract_number_and_incr _RE_ARGS((int *destination,
+											  unsigned char **source));
+static void extract_number_and_incr(destination, source)
+int *destination;
+unsigned char **source;
+{
+	extract_number(destination, *source);
+	*source += 2;
+}
+
+# ifndef EXTRACT_MACROS
+#  undef EXTRACT_NUMBER_AND_INCR
+#  define EXTRACT_NUMBER_AND_INCR(dest, src) \
+  extract_number_and_incr (&dest, &src)
+# endif							/* not EXTRACT_MACROS */
+
+#endif							/* DEBUG */
+
+/* If DEBUG is defined, Regex prints many voluminous messages about what
+   it is doing (if the variable `debug' is nonzero).  If linked with the
+   main program in `iregex.c', you can enter patterns and strings
+   interactively.  And if linked with the main program in `main.c' and
+   the other test files, you can run the already-written tests.  */
+
+#ifdef DEBUG
+
+/* We use standard I/O for debugging.  */
+# include <stdio.h>
+
+/* It is useful to test things that ``must'' be true when debugging.  */
+# include <assert.h>
+
+static int debug;
+
+# define DEBUG_STATEMENT(e) e
+# define DEBUG_PRINT1(x) if (debug) printf (x)
+# define DEBUG_PRINT2(x1, x2) if (debug) printf (x1, x2)
+# define DEBUG_PRINT3(x1, x2, x3) if (debug) printf (x1, x2, x3)
+# define DEBUG_PRINT4(x1, x2, x3, x4) if (debug) printf (x1, x2, x3, x4)
+# define DEBUG_PRINT_COMPILED_PATTERN(p, s, e) 				\
+  if (debug) print_partial_compiled_pattern (s, e)
+# define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2)			\
+  if (debug) print_double_string (w, s1, sz1, s2, sz2)
+
+
+/* Print the fastmap in human-readable form.  */
+
+void print_fastmap(fastmap)
+char *fastmap;
+{
+	unsigned was_a_range = 0;
+	unsigned i = 0;
+
+	while (i < (1 << BYTEWIDTH)) {
+		if (fastmap[i++]) {
+			was_a_range = 0;
+			putchar(i - 1);
+			while (i < (1 << BYTEWIDTH) && fastmap[i]) {
+				was_a_range = 1;
+				i++;
+			}
+			if (was_a_range) {
+				printf("-");
+				putchar(i - 1);
+			}
+		}
+	}
+	putchar('\n');
+}
+
+
+/* Print a compiled pattern string in human-readable form, starting at
+   the START pointer into it and ending just before the pointer END.  */
+
+void print_partial_compiled_pattern(start, end)
+unsigned char *start;
+unsigned char *end;
+{
+	int mcnt, mcnt2;
+	unsigned char *p1;
+	unsigned char *p = start;
+	unsigned char *pend = end;
+
+	if (start == NULL) {
+		printf("(null)\n");
+		return;
+	}
+
+	/* Loop over pattern commands.  */
+	while (p < pend) {
+		printf("%d:\t", p - start);
+
+		switch ((re_opcode_t) * p++) {
+		case no_op:
+			printf("/no_op");
+			break;
+
+		case exactn:
+			mcnt = *p++;
+			printf("/exactn/%d", mcnt);
+			do {
+				putchar('/');
+				putchar(*p++);
+			}
+			while (--mcnt);
+			break;
+
+		case start_memory:
+			mcnt = *p++;
+			printf("/start_memory/%d/%d", mcnt, *p++);
+			break;
+
+		case stop_memory:
+			mcnt = *p++;
+			printf("/stop_memory/%d/%d", mcnt, *p++);
+			break;
+
+		case duplicate:
+			printf("/duplicate/%d", *p++);
+			break;
+
+		case anychar:
+			printf("/anychar");
+			break;
+
+		case charset:
+		case charset_not:
+		{
+			register int c, last = -100;
+			register int in_range = 0;
+
+			printf("/charset [%s",
+				   (re_opcode_t) * (p - 1) == charset_not ? "^" : "");
+
+			assert(p + *p < pend);
+
+			for (c = 0; c < 256; c++)
+				if (c / 8 < *p && (p[1 + (c / 8)] & (1 << (c % 8)))) {
+					/* Are we starting a range?  */
+					if (last + 1 == c && !in_range) {
+						putchar('-');
+						in_range = 1;
+					}
+					/* Have we broken a range?  */
+					else if (last + 1 != c && in_range) {
+						putchar(last);
+						in_range = 0;
+					}
+
+					if (!in_range)
+						putchar(c);
+
+					last = c;
+				}
+
+			if (in_range)
+				putchar(last);
+
+			putchar(']');
+
+			p += 1 + *p;
+		}
+			break;
+
+		case begline:
+			printf("/begline");
+			break;
+
+		case endline:
+			printf("/endline");
+			break;
+
+		case on_failure_jump:
+			extract_number_and_incr(&mcnt, &p);
+			printf("/on_failure_jump to %d", p + mcnt - start);
+			break;
+
+		case on_failure_keep_string_jump:
+			extract_number_and_incr(&mcnt, &p);
+			printf("/on_failure_keep_string_jump to %d", p + mcnt - start);
+			break;
+
+		case dummy_failure_jump:
+			extract_number_and_incr(&mcnt, &p);
+			printf("/dummy_failure_jump to %d", p + mcnt - start);
+			break;
+
+		case push_dummy_failure:
+			printf("/push_dummy_failure");
+			break;
+
+		case maybe_pop_jump:
+			extract_number_and_incr(&mcnt, &p);
+			printf("/maybe_pop_jump to %d", p + mcnt - start);
+			break;
+
+		case pop_failure_jump:
+			extract_number_and_incr(&mcnt, &p);
+			printf("/pop_failure_jump to %d", p + mcnt - start);
+			break;
+
+		case jump_past_alt:
+			extract_number_and_incr(&mcnt, &p);
+			printf("/jump_past_alt to %d", p + mcnt - start);
+			break;
+
+		case jump:
+			extract_number_and_incr(&mcnt, &p);
+			printf("/jump to %d", p + mcnt - start);
+			break;
+
+		case succeed_n:
+			extract_number_and_incr(&mcnt, &p);
+			p1 = p + mcnt;
+			extract_number_and_incr(&mcnt2, &p);
+			printf("/succeed_n to %d, %d times", p1 - start, mcnt2);
+			break;
+
+		case jump_n:
+			extract_number_and_incr(&mcnt, &p);
+			p1 = p + mcnt;
+			extract_number_and_incr(&mcnt2, &p);
+			printf("/jump_n to %d, %d times", p1 - start, mcnt2);
+			break;
+
+		case set_number_at:
+			extract_number_and_incr(&mcnt, &p);
+			p1 = p + mcnt;
+			extract_number_and_incr(&mcnt2, &p);
+			printf("/set_number_at location %d to %d", p1 - start, mcnt2);
+			break;
+
+		case wordbound:
+			printf("/wordbound");
+			break;
+
+		case notwordbound:
+			printf("/notwordbound");
+			break;
+
+		case wordbeg:
+			printf("/wordbeg");
+			break;
+
+		case wordend:
+			printf("/wordend");
+
+# ifdef emacs
+		case before_dot:
+			printf("/before_dot");
+			break;
+
+		case at_dot:
+			printf("/at_dot");
+			break;
+
+		case after_dot:
+			printf("/after_dot");
+			break;
+
+		case syntaxspec:
+			printf("/syntaxspec");
+			mcnt = *p++;
+			printf("/%d", mcnt);
+			break;
+
+		case notsyntaxspec:
+			printf("/notsyntaxspec");
+			mcnt = *p++;
+			printf("/%d", mcnt);
+			break;
+# endif							/* emacs */
+
+		case wordchar:
+			printf("/wordchar");
+			break;
+
+		case notwordchar:
+			printf("/notwordchar");
+			break;
+
+		case begbuf:
+			printf("/begbuf");
+			break;
+
+		case endbuf:
+			printf("/endbuf");
+			break;
+
+		default:
+			printf("?%d", *(p - 1));
+		}
+
+		putchar('\n');
+	}
+
+	printf("%d:\tend of pattern.\n", p - start);
+}
+
+
+void print_compiled_pattern(bufp)
+struct re_pattern_buffer *bufp;
+{
+	unsigned char *buffer = bufp->buffer;
+
+	print_partial_compiled_pattern(buffer, buffer + bufp->used);
+	printf("%ld bytes used/%ld bytes allocated.\n",
+		   bufp->used, bufp->allocated);
+
+	if (bufp->fastmap_accurate && bufp->fastmap) {
+		printf("fastmap: ");
+		print_fastmap(bufp->fastmap);
+	}
+
+	printf("re_nsub: %d\t", bufp->re_nsub);
+	printf("regs_alloc: %d\t", bufp->regs_allocated);
+	printf("can_be_null: %d\t", bufp->can_be_null);
+	printf("newline_anchor: %d\n", bufp->newline_anchor);
+	printf("no_sub: %d\t", bufp->no_sub);
+	printf("not_bol: %d\t", bufp->not_bol);
+	printf("not_eol: %d\t", bufp->not_eol);
+	printf("syntax: %lx\n", bufp->syntax);
+	/* Perhaps we should print the translate table?  */
+}
+
+
+void print_double_string(where, string1, size1, string2, size2)
+const char *where;
+const char *string1;
+const char *string2;
+int size1;
+int size2;
+{
+	int this_char;
+
+	if (where == NULL)
+		printf("(null)");
+	else {
+		if (FIRST_STRING_P(where)) {
+			for (this_char = where - string1; this_char < size1;
+				 this_char++)
+				putchar(string1[this_char]);
+
+			where = string2;
+		}
+
+		for (this_char = where - string2; this_char < size2; this_char++)
+			putchar(string2[this_char]);
+	}
+}
+
+void printchar(c)
+int c;
+{
+	putc(c, stderr);
+}
+
+#else							/* not DEBUG */
+
+# undef assert
+# define assert(e)
+
+# define DEBUG_STATEMENT(e)
+# define DEBUG_PRINT1(x)
+# define DEBUG_PRINT2(x1, x2)
+# define DEBUG_PRINT3(x1, x2, x3)
+# define DEBUG_PRINT4(x1, x2, x3, x4)
+# define DEBUG_PRINT_COMPILED_PATTERN(p, s, e)
+# define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2)
+
+#endif							/* not DEBUG */
+
+/* Set by `re_set_syntax' to the current regexp syntax to recognize.  Can
+   also be assigned to arbitrarily: each pattern buffer stores its own
+   syntax, so it can be changed between regex compilations.  */
+/* This has no initializer because initialized variables in Emacs
+   become read-only after dumping.  */
+reg_syntax_t re_syntax_options;
+
+
+/* Specify the precise syntax of regexps for compilation.  This provides
+   for compatibility for various utilities which historically have
+   different, incompatible syntaxes.
+
+   The argument SYNTAX is a bit mask comprised of the various bits
+   defined in regex.h.  We return the old syntax.  */
+
+reg_syntax_t re_set_syntax(syntax)
+reg_syntax_t syntax;
+{
+	reg_syntax_t ret = re_syntax_options;
+
+	re_syntax_options = syntax;
+#ifdef DEBUG
+	if (syntax & RE_DEBUG)
+		debug = 1;
+	else if (debug)				/* was on but now is not */
+		debug = 0;
+#endif							/* DEBUG */
+	return ret;
+}
+
+#ifdef _LIBC
+weak_alias(__re_set_syntax, re_set_syntax)
+#endif
+/* This table gives an error message for each of the error codes listed
+   in regex.h.  Obviously the order here has to be same as there.
+   POSIX doesn't require that we do anything for REG_NOERROR,
+   but why not be nice?  */
+static const char re_error_msgid[] = {
+#define REG_NOERROR_IDX	0
+	gettext_noop("Success")		/* REG_NOERROR */
+		"\0"
+#define REG_NOMATCH_IDX (REG_NOERROR_IDX + sizeof "Success")
+		gettext_noop("No match")	/* REG_NOMATCH */
+		"\0"
+#define REG_BADPAT_IDX	(REG_NOMATCH_IDX + sizeof "No match")
+		gettext_noop("Invalid regular expression")	/* REG_BADPAT */
+		"\0"
+#define REG_ECOLLATE_IDX (REG_BADPAT_IDX + sizeof "Invalid regular expression")
+		gettext_noop("Invalid collation character")	/* REG_ECOLLATE */
+		"\0"
+#define REG_ECTYPE_IDX	(REG_ECOLLATE_IDX + sizeof "Invalid collation character")
+		gettext_noop("Invalid character class name")	/* REG_ECTYPE */
+		"\0"
+#define REG_EESCAPE_IDX	(REG_ECTYPE_IDX + sizeof "Invalid character class name")
+		gettext_noop("Trailing backslash")	/* REG_EESCAPE */
+		"\0"
+#define REG_ESUBREG_IDX	(REG_EESCAPE_IDX + sizeof "Trailing backslash")
+		gettext_noop("Invalid back reference")	/* REG_ESUBREG */
+		"\0"
+#define REG_EBRACK_IDX	(REG_ESUBREG_IDX + sizeof "Invalid back reference")
+		gettext_noop("Unmatched [ or [^")	/* REG_EBRACK */
+		"\0"
+#define REG_EPAREN_IDX	(REG_EBRACK_IDX + sizeof "Unmatched [ or [^")
+		gettext_noop("Unmatched ( or \\(")	/* REG_EPAREN */
+		"\0"
+#define REG_EBRACE_IDX	(REG_EPAREN_IDX + sizeof "Unmatched ( or \\(")
+		gettext_noop("Unmatched \\{")	/* REG_EBRACE */
+		"\0"
+#define REG_BADBR_IDX	(REG_EBRACE_IDX + sizeof "Unmatched \\{")
+		gettext_noop("Invalid content of \\{\\}")	/* REG_BADBR */
+		"\0"
+#define REG_ERANGE_IDX	(REG_BADBR_IDX + sizeof "Invalid content of \\{\\}")
+		gettext_noop("Invalid range end")	/* REG_ERANGE */
+		"\0"
+#define REG_ESPACE_IDX	(REG_ERANGE_IDX + sizeof "Invalid range end")
+		gettext_noop("Memory exhausted")	/* REG_ESPACE */
+		"\0"
+#define REG_BADRPT_IDX	(REG_ESPACE_IDX + sizeof "Memory exhausted")
+		gettext_noop("Invalid preceding regular expression")	/* REG_BADRPT */
+		"\0"
+#define REG_EEND_IDX	(REG_BADRPT_IDX + sizeof "Invalid preceding regular expression")
+		gettext_noop("Premature end of regular expression")	/* REG_EEND */
+		"\0"
+#define REG_ESIZE_IDX	(REG_EEND_IDX + sizeof "Premature end of regular expression")
+		gettext_noop("Regular expression too big")	/* REG_ESIZE */
+		"\0"
+#define REG_ERPAREN_IDX	(REG_ESIZE_IDX + sizeof "Regular expression too big")
+		gettext_noop("Unmatched ) or \\)")	/* REG_ERPAREN */
+};
+
+static const size_t re_error_msgid_idx[] = {
+	REG_NOERROR_IDX,
+	REG_NOMATCH_IDX,
+	REG_BADPAT_IDX,
+	REG_ECOLLATE_IDX,
+	REG_ECTYPE_IDX,
+	REG_EESCAPE_IDX,
+	REG_ESUBREG_IDX,
+	REG_EBRACK_IDX,
+	REG_EPAREN_IDX,
+	REG_EBRACE_IDX,
+	REG_BADBR_IDX,
+	REG_ERANGE_IDX,
+	REG_ESPACE_IDX,
+	REG_BADRPT_IDX,
+	REG_EEND_IDX,
+	REG_ESIZE_IDX,
+	REG_ERPAREN_IDX
+};
+
+/* Avoiding alloca during matching, to placate r_alloc.  */
+
+/* Define MATCH_MAY_ALLOCATE unless we need to make sure that the
+   searching and matching functions should not call alloca.  On some
+   systems, alloca is implemented in terms of malloc, and if we're
+   using the relocating allocator routines, then malloc could cause a
+   relocation, which might (if the strings being searched are in the
+   ralloc heap) shift the data out from underneath the regexp
+   routines.
+
+   Here's another reason to avoid allocation: Emacs
+   processes input from X in a signal handler; processing X input may
+   call malloc; if input arrives while a matching routine is calling
+   malloc, then we're scrod.  But Emacs can't just block input while
+   calling matching routines; then we don't notice interrupts when
+   they come in.  So, Emacs blocks input around all regexp calls
+   except the matching calls, which it leaves unprotected, in the
+   faith that they will not malloc.  */
+
+/* Normally, this is fine.  */
+#define MATCH_MAY_ALLOCATE
+
+/* When using GNU C, we are not REALLY using the C alloca, no matter
+   what config.h may say.  So don't take precautions for it.  */
+#ifdef __GNUC__
+# undef C_ALLOCA
+#endif
+
+/* The match routines may not allocate if (1) they would do it with malloc
+   and (2) it's not safe for them to use malloc.
+   Note that if REL_ALLOC is defined, matching would not use malloc for the
+   failure stack, but we would still use it for the register vectors;
+   so REL_ALLOC should not affect this.  */
+#if (defined C_ALLOCA || defined REGEX_MALLOC) && defined emacs
+# undef MATCH_MAY_ALLOCATE
+#endif
+
+
+/* Failure stack declarations and macros; both re_compile_fastmap and
+   re_match_2 use a failure stack.  These have to be macros because of
+   REGEX_ALLOCATE_STACK.  */
+
+
+/* Number of failure points for which to initially allocate space
+   when matching.  If this number is exceeded, we allocate more
+   space, so it is not a hard limit.  */
+#ifndef INIT_FAILURE_ALLOC
+# define INIT_FAILURE_ALLOC 5
+#endif
+
+/* Roughly the maximum number of failure points on the stack.  Would be
+   exactly that if always used MAX_FAILURE_ITEMS items each time we failed.
+   This is a variable only so users of regex can assign to it; we never
+   change it ourselves.  */
+
+#ifdef INT_IS_16BIT
+
+# if defined MATCH_MAY_ALLOCATE
+/* 4400 was enough to cause a crash on Alpha OSF/1,
+   whose default stack limit is 2mb.  */
+long int re_max_failures = 4000;
+# else
+long int re_max_failures = 2000;
+# endif
+
+union fail_stack_elt {
+	unsigned char *pointer;
+	long int integer;
+};
+
+typedef union fail_stack_elt fail_stack_elt_t;
+
+typedef struct {
+	fail_stack_elt_t *stack;
+	unsigned long int size;
+	unsigned long int avail;	/* Offset of next open position.  */
+} fail_stack_type;
+
+#else							/* not INT_IS_16BIT */
+
+# if defined MATCH_MAY_ALLOCATE
+/* 4400 was enough to cause a crash on Alpha OSF/1,
+   whose default stack limit is 2mb.  */
+int re_max_failures = 20000;
+# else
+int re_max_failures = 2000;
+# endif
+
+union fail_stack_elt {
+	unsigned char *pointer;
+	int integer;
+};
+
+typedef union fail_stack_elt fail_stack_elt_t;
+
+typedef struct {
+	fail_stack_elt_t *stack;
+	unsigned size;
+	unsigned avail;				/* Offset of next open position.  */
+} fail_stack_type;
+
+#endif							/* INT_IS_16BIT */
+
+#define FAIL_STACK_EMPTY()     (fail_stack.avail == 0)
+#define FAIL_STACK_PTR_EMPTY() (fail_stack_ptr->avail == 0)
+#define FAIL_STACK_FULL()      (fail_stack.avail == fail_stack.size)
+
+
+/* Define macros to initialize and free the failure stack.
+   Do `return -2' if the alloc fails.  */
+
+#ifdef MATCH_MAY_ALLOCATE
+# define INIT_FAIL_STACK()						\
+  do {									\
+    fail_stack.stack = (fail_stack_elt_t *)				\
+      REGEX_ALLOCATE_STACK (INIT_FAILURE_ALLOC * sizeof (fail_stack_elt_t)); \
+									\
+    if (fail_stack.stack == NULL)					\
+      return -2;							\
+									\
+    fail_stack.size = INIT_FAILURE_ALLOC;				\
+    fail_stack.avail = 0;						\
+  } while (0)
+
+# define RESET_FAIL_STACK()  REGEX_FREE_STACK (fail_stack.stack)
+#else
+# define INIT_FAIL_STACK()						\
+  do {									\
+    fail_stack.avail = 0;						\
+  } while (0)
+
+# define RESET_FAIL_STACK()
+#endif
+
+
+/* Double the size of FAIL_STACK, up to approximately `re_max_failures' items.
+
+   Return 1 if succeeds, and 0 if either ran out of memory
+   allocating space for it or it was already too large.
+
+   REGEX_REALLOCATE_STACK requires `destination' be declared.   */
+
+#define DOUBLE_FAIL_STACK(fail_stack)					\
+  ((fail_stack).size > (unsigned) (re_max_failures * MAX_FAILURE_ITEMS)	\
+   ? 0									\
+   : ((fail_stack).stack = (fail_stack_elt_t *)				\
+        REGEX_REALLOCATE_STACK ((fail_stack).stack, 			\
+          (fail_stack).size * sizeof (fail_stack_elt_t),		\
+          ((fail_stack).size << 1) * sizeof (fail_stack_elt_t)),	\
+									\
+      (fail_stack).stack == NULL					\
+      ? 0								\
+      : ((fail_stack).size <<= 1, 					\
+         1)))
+
+
+/* Push pointer POINTER on FAIL_STACK.
+   Return 1 if was able to do so and 0 if ran out of memory allocating
+   space to do so.  */
+#define PUSH_PATTERN_OP(POINTER, FAIL_STACK)				\
+  ((FAIL_STACK_FULL ()							\
+    && !DOUBLE_FAIL_STACK (FAIL_STACK))					\
+   ? 0									\
+   : ((FAIL_STACK).stack[(FAIL_STACK).avail++].pointer = POINTER,	\
+      1))
+
+/* Push a pointer value onto the failure stack.
+   Assumes the variable `fail_stack'.  Probably should only
+   be called from within `PUSH_FAILURE_POINT'.  */
+#define PUSH_FAILURE_POINTER(item)					\
+  fail_stack.stack[fail_stack.avail++].pointer = (unsigned char *) (item)
+
+/* This pushes an integer-valued item onto the failure stack.
+   Assumes the variable `fail_stack'.  Probably should only
+   be called from within `PUSH_FAILURE_POINT'.  */
+#define PUSH_FAILURE_INT(item)					\
+  fail_stack.stack[fail_stack.avail++].integer = (item)
+
+/* Push a fail_stack_elt_t value onto the failure stack.
+   Assumes the variable `fail_stack'.  Probably should only
+   be called from within `PUSH_FAILURE_POINT'.  */
+#define PUSH_FAILURE_ELT(item)					\
+  fail_stack.stack[fail_stack.avail++] =  (item)
+
+/* These three POP... operations complement the three PUSH... operations.
+   All assume that `fail_stack' is nonempty.  */
+#define POP_FAILURE_POINTER() fail_stack.stack[--fail_stack.avail].pointer
+#define POP_FAILURE_INT() fail_stack.stack[--fail_stack.avail].integer
+#define POP_FAILURE_ELT() fail_stack.stack[--fail_stack.avail]
+
+/* Used to omit pushing failure point id's when we're not debugging.  */
+#ifdef DEBUG
+# define DEBUG_PUSH PUSH_FAILURE_INT
+# define DEBUG_POP(item_addr) *(item_addr) = POP_FAILURE_INT ()
+#else
+# define DEBUG_PUSH(item)
+# define DEBUG_POP(item_addr)
+#endif
+
+
+/* Push the information about the state we will need
+   if we ever fail back to it.
+
+   Requires variables fail_stack, regstart, regend, reg_info, and
+   num_regs_pushed be declared.  DOUBLE_FAIL_STACK requires `destination'
+   be declared.
+
+   Does `return FAILURE_CODE' if runs out of memory.  */
+
+#define PUSH_FAILURE_POINT(pattern_place, string_place, failure_code)	\
+  do {									\
+    char *destination;							\
+    /* Must be int, so when we don't save any registers, the arithmetic	\
+       of 0 + -1 isn't done as unsigned.  */				\
+    /* Can't be int, since there is not a shred of a guarantee that int	\
+       is wide enough to hold a value of something to which pointer can	\
+       be assigned */							\
+    active_reg_t this_reg;						\
+    									\
+    DEBUG_STATEMENT (failure_id++);					\
+    DEBUG_STATEMENT (nfailure_points_pushed++);				\
+    DEBUG_PRINT2 ("\nPUSH_FAILURE_POINT #%u:\n", failure_id);		\
+    DEBUG_PRINT2 ("  Before push, next avail: %d\n", (fail_stack).avail);\
+    DEBUG_PRINT2 ("                     size: %d\n", (fail_stack).size);\
+									\
+    DEBUG_PRINT2 ("  slots needed: %ld\n", NUM_FAILURE_ITEMS);		\
+    DEBUG_PRINT2 ("     available: %d\n", REMAINING_AVAIL_SLOTS);	\
+									\
+    /* Ensure we have enough space allocated for what we will push.  */	\
+    while (REMAINING_AVAIL_SLOTS < NUM_FAILURE_ITEMS)			\
+      {									\
+        if (!DOUBLE_FAIL_STACK (fail_stack))				\
+          return failure_code;						\
+									\
+        DEBUG_PRINT2 ("\n  Doubled stack; size now: %d\n",		\
+		       (fail_stack).size);				\
+        DEBUG_PRINT2 ("  slots available: %d\n", REMAINING_AVAIL_SLOTS);\
+      }									\
+									\
+    /* Push the info, starting with the registers.  */			\
+    DEBUG_PRINT1 ("\n");						\
+									\
+    if (1)								\
+      for (this_reg = lowest_active_reg; this_reg <= highest_active_reg; \
+	   this_reg++)							\
+	{								\
+	  DEBUG_PRINT2 ("  Pushing reg: %lu\n", this_reg);		\
+	  DEBUG_STATEMENT (num_regs_pushed++);				\
+									\
+	  DEBUG_PRINT2 ("    start: %p\n", regstart[this_reg]);		\
+	  PUSH_FAILURE_POINTER (regstart[this_reg]);			\
+									\
+	  DEBUG_PRINT2 ("    end: %p\n", regend[this_reg]);		\
+	  PUSH_FAILURE_POINTER (regend[this_reg]);			\
+									\
+	  DEBUG_PRINT2 ("    info: %p\n      ",				\
+			reg_info[this_reg].word.pointer);		\
+	  DEBUG_PRINT2 (" match_null=%d",				\
+			REG_MATCH_NULL_STRING_P (reg_info[this_reg]));	\
+	  DEBUG_PRINT2 (" active=%d", IS_ACTIVE (reg_info[this_reg]));	\
+	  DEBUG_PRINT2 (" matched_something=%d",			\
+			MATCHED_SOMETHING (reg_info[this_reg]));	\
+	  DEBUG_PRINT2 (" ever_matched=%d",				\
+			EVER_MATCHED_SOMETHING (reg_info[this_reg]));	\
+	  DEBUG_PRINT1 ("\n");						\
+	  PUSH_FAILURE_ELT (reg_info[this_reg].word);			\
+	}								\
+									\
+    DEBUG_PRINT2 ("  Pushing  low active reg: %ld\n", lowest_active_reg);\
+    PUSH_FAILURE_INT (lowest_active_reg);				\
+									\
+    DEBUG_PRINT2 ("  Pushing high active reg: %ld\n", highest_active_reg);\
+    PUSH_FAILURE_INT (highest_active_reg);				\
+									\
+    DEBUG_PRINT2 ("  Pushing pattern %p:\n", pattern_place);		\
+    DEBUG_PRINT_COMPILED_PATTERN (bufp, pattern_place, pend);		\
+    PUSH_FAILURE_POINTER (pattern_place);				\
+									\
+    DEBUG_PRINT2 ("  Pushing string %p: `", string_place);		\
+    DEBUG_PRINT_DOUBLE_STRING (string_place, string1, size1, string2,   \
+				 size2);				\
+    DEBUG_PRINT1 ("'\n");						\
+    PUSH_FAILURE_POINTER (string_place);				\
+									\
+    DEBUG_PRINT2 ("  Pushing failure id: %u\n", failure_id);		\
+    DEBUG_PUSH (failure_id);						\
+  } while (0)
+
+/* This is the number of items that are pushed and popped on the stack
+   for each register.  */
+#define NUM_REG_ITEMS  3
+
+/* Individual items aside from the registers.  */
+#ifdef DEBUG
+# define NUM_NONREG_ITEMS 5		/* Includes failure point id.  */
+#else
+# define NUM_NONREG_ITEMS 4
+#endif
+
+/* We push at most this many items on the stack.  */
+/* We used to use (num_regs - 1), which is the number of registers
+   this regexp will save; but that was changed to 5
+   to avoid stack overflow for a regexp with lots of parens.  */
+#define MAX_FAILURE_ITEMS (5 * NUM_REG_ITEMS + NUM_NONREG_ITEMS)
+
+/* We actually push this many items.  */
+#define NUM_FAILURE_ITEMS				\
+  (((0							\
+     ? 0 : highest_active_reg - lowest_active_reg + 1)	\
+    * NUM_REG_ITEMS)					\
+   + NUM_NONREG_ITEMS)
+
+/* How many items can still be added to the stack without overflowing it.  */
+#define REMAINING_AVAIL_SLOTS ((fail_stack).size - (fail_stack).avail)
+
+
+/* Pops what PUSH_FAIL_STACK pushes.
+
+   We restore into the parameters, all of which should be lvalues:
+     STR -- the saved data position.
+     PAT -- the saved pattern position.
+     LOW_REG, HIGH_REG -- the highest and lowest active registers.
+     REGSTART, REGEND -- arrays of string positions.
+     REG_INFO -- array of information about each subexpression.
+
+   Also assumes the variables `fail_stack' and (if debugging), `bufp',
+   `pend', `string1', `size1', `string2', and `size2'.  */
+
+#define POP_FAILURE_POINT(str, pat, low_reg, high_reg, regstart, regend, reg_info)\
+{									\
+  DEBUG_STATEMENT (unsigned failure_id;)				\
+  active_reg_t this_reg;						\
+  const unsigned char *string_temp;					\
+									\
+  assert (!FAIL_STACK_EMPTY ());					\
+									\
+  /* Remove failure points and point to how many regs pushed.  */	\
+  DEBUG_PRINT1 ("POP_FAILURE_POINT:\n");				\
+  DEBUG_PRINT2 ("  Before pop, next avail: %d\n", fail_stack.avail);	\
+  DEBUG_PRINT2 ("                    size: %d\n", fail_stack.size);	\
+									\
+  assert (fail_stack.avail >= NUM_NONREG_ITEMS);			\
+									\
+  DEBUG_POP (&failure_id);						\
+  DEBUG_PRINT2 ("  Popping failure id: %u\n", failure_id);		\
+									\
+  /* If the saved string location is NULL, it came from an		\
+     on_failure_keep_string_jump opcode, and we want to throw away the	\
+     saved NULL, thus retaining our current position in the string.  */	\
+  string_temp = POP_FAILURE_POINTER ();					\
+  if (string_temp != NULL)						\
+    str = (const char *) string_temp;					\
+									\
+  DEBUG_PRINT2 ("  Popping string %p: `", str);				\
+  DEBUG_PRINT_DOUBLE_STRING (str, string1, size1, string2, size2);	\
+  DEBUG_PRINT1 ("'\n");							\
+									\
+  pat = (unsigned char *) POP_FAILURE_POINTER ();			\
+  DEBUG_PRINT2 ("  Popping pattern %p:\n", pat);			\
+  DEBUG_PRINT_COMPILED_PATTERN (bufp, pat, pend);			\
+									\
+  /* Restore register info.  */						\
+  high_reg = (active_reg_t) POP_FAILURE_INT ();				\
+  DEBUG_PRINT2 ("  Popping high active reg: %ld\n", high_reg);		\
+									\
+  low_reg = (active_reg_t) POP_FAILURE_INT ();				\
+  DEBUG_PRINT2 ("  Popping  low active reg: %ld\n", low_reg);		\
+									\
+  if (1)								\
+    for (this_reg = high_reg; this_reg >= low_reg; this_reg--)		\
+      {									\
+	DEBUG_PRINT2 ("    Popping reg: %ld\n", this_reg);		\
+									\
+	reg_info[this_reg].word = POP_FAILURE_ELT ();			\
+	DEBUG_PRINT2 ("      info: %p\n",				\
+		      reg_info[this_reg].word.pointer);			\
+									\
+	regend[this_reg] = (const char *) POP_FAILURE_POINTER ();	\
+	DEBUG_PRINT2 ("      end: %p\n", regend[this_reg]);		\
+									\
+	regstart[this_reg] = (const char *) POP_FAILURE_POINTER ();	\
+	DEBUG_PRINT2 ("      start: %p\n", regstart[this_reg]);		\
+      }									\
+  else									\
+    {									\
+      for (this_reg = highest_active_reg; this_reg > high_reg; this_reg--) \
+	{								\
+	  reg_info[this_reg].word.integer = 0;				\
+	  regend[this_reg] = 0;						\
+	  regstart[this_reg] = 0;					\
+	}								\
+      highest_active_reg = high_reg;					\
+    }									\
+									\
+  set_regs_matched_done = 0;						\
+  DEBUG_STATEMENT (nfailure_points_popped++);				\
+}								/* POP_FAILURE_POINT */
+
+
+
+/* Structure for per-register (a.k.a. per-group) information.
+   Other register information, such as the
+   starting and ending positions (which are addresses), and the list of
+   inner groups (which is a bits list) are maintained in separate
+   variables.
+
+   We are making a (strictly speaking) nonportable assumption here: that
+   the compiler will pack our bit fields into something that fits into
+   the type of `word', i.e., is something that fits into one item on the
+   failure stack.  */
+
+
+/* Declarations and macros for re_match_2.  */
+
+typedef union {
+	fail_stack_elt_t word;
+	struct {
+		/* This field is one if this group can match the empty string,
+		   zero if not.  If not yet determined,  `MATCH_NULL_UNSET_VALUE'.  */
+#define MATCH_NULL_UNSET_VALUE 3
+		unsigned match_null_string_p:2;
+		unsigned is_active:1;
+		unsigned matched_something:1;
+		unsigned ever_matched_something:1;
+	} bits;
+} register_info_type;
+
+#define REG_MATCH_NULL_STRING_P(R)  ((R).bits.match_null_string_p)
+#define IS_ACTIVE(R)  ((R).bits.is_active)
+#define MATCHED_SOMETHING(R)  ((R).bits.matched_something)
+#define EVER_MATCHED_SOMETHING(R)  ((R).bits.ever_matched_something)
+
+
+/* Call this when have matched a real character; it sets `matched' flags
+   for the subexpressions which we are currently inside.  Also records
+   that those subexprs have matched.  */
+#define SET_REGS_MATCHED()						\
+  do									\
+    {									\
+      if (!set_regs_matched_done)					\
+	{								\
+	  active_reg_t r;						\
+	  set_regs_matched_done = 1;					\
+	  for (r = lowest_active_reg; r <= highest_active_reg; r++)	\
+	    {								\
+	      MATCHED_SOMETHING (reg_info[r])				\
+		= EVER_MATCHED_SOMETHING (reg_info[r])			\
+		= 1;							\
+	    }								\
+	}								\
+    }									\
+  while (0)
+
+/* Registers are set to a sentinel when they haven't yet matched.  */
+static char reg_unset_dummy;
+
+#define REG_UNSET_VALUE (&reg_unset_dummy)
+#define REG_UNSET(e) ((e) == REG_UNSET_VALUE)
+
+/* Subroutine declarations and macros for regex_compile.  */
+
+static reg_errcode_t regex_compile
+_RE_ARGS(
+		 (const char *pattern, size_t size, reg_syntax_t syntax,
+		  struct re_pattern_buffer * bufp));
+static void store_op1
+
+_RE_ARGS((re_opcode_t op, unsigned char *loc, int arg));
+static void store_op2
+_RE_ARGS((re_opcode_t op, unsigned char *loc, int arg1, int arg2));
+static void insert_op1
+_RE_ARGS(
+
+		 (re_opcode_t op, unsigned char *loc, int arg,
+		  unsigned char *end));
+static void insert_op2
+_RE_ARGS(
+		 (re_opcode_t op, unsigned char *loc, int arg1, int arg2,
+
+		  unsigned char *end));
+static boolean at_begline_loc_p
+_RE_ARGS((const char *pattern, const char *p, reg_syntax_t syntax));
+static boolean at_endline_loc_p
+_RE_ARGS((const char *p, const char *pend, reg_syntax_t syntax));
+static reg_errcode_t compile_range
+_RE_ARGS(
+		 (const char **p_ptr, const char *pend, char *translate,
+		  reg_syntax_t syntax, unsigned char *b));
+
+/* Fetch the next character in the uncompiled pattern---translating it
+   if necessary.  Also cast from a signed character in the constant
+   string passed to us by the user to an unsigned char that we can use
+   as an array index (in, e.g., `translate').  */
+#ifndef PATFETCH
+# define PATFETCH(c)							\
+  do {if (p == pend) return REG_EEND;					\
+    c = (unsigned char) *p++;						\
+    if (translate) c = (unsigned char) translate[c];			\
+  } while (0)
+#endif
+
+/* Fetch the next character in the uncompiled pattern, with no
+   translation.  */
+#define PATFETCH_RAW(c)							\
+  do {if (p == pend) return REG_EEND;					\
+    c = (unsigned char) *p++; 						\
+  } while (0)
+
+/* Go backwards one character in the pattern.  */
+#define PATUNFETCH p--
+
+
+/* If `translate' is non-null, return translate[D], else just D.  We
+   cast the subscript to translate because some data is declared as
+   `char *', to avoid warnings when a string constant is passed.  But
+   when we use a character as a subscript we must make it unsigned.  */
+#ifndef TRANSLATE
+# define TRANSLATE(d) \
+  (translate ? (char) translate[(unsigned char) (d)] : (d))
+#endif
+
+
+/* Macros for outputting the compiled pattern into `buffer'.  */
+
+/* If the buffer isn't allocated when it comes in, use this.  */
+#define INIT_BUF_SIZE  32
+
+/* Make sure we have at least N more bytes of space in buffer.  */
+#define GET_BUFFER_SPACE(n)						\
+    while ((unsigned long) (b - bufp->buffer + (n)) > bufp->allocated)	\
+      EXTEND_BUFFER ()
+
+/* Make sure we have one more byte of buffer space and then add C to it.  */
+#define BUF_PUSH(c)							\
+  do {									\
+    GET_BUFFER_SPACE (1);						\
+    *b++ = (unsigned char) (c);						\
+  } while (0)
+
+
+/* Ensure we have two more bytes of buffer space and then append C1 and C2.  */
+#define BUF_PUSH_2(c1, c2)						\
+  do {									\
+    GET_BUFFER_SPACE (2);						\
+    *b++ = (unsigned char) (c1);					\
+    *b++ = (unsigned char) (c2);					\
+  } while (0)
+
+
+/* As with BUF_PUSH_2, except for three bytes.  */
+#define BUF_PUSH_3(c1, c2, c3)						\
+  do {									\
+    GET_BUFFER_SPACE (3);						\
+    *b++ = (unsigned char) (c1);					\
+    *b++ = (unsigned char) (c2);					\
+    *b++ = (unsigned char) (c3);					\
+  } while (0)
+
+
+/* Store a jump with opcode OP at LOC to location TO.  We store a
+   relative address offset by the three bytes the jump itself occupies.  */
+#define STORE_JUMP(op, loc, to) \
+  store_op1 (op, loc, (int) ((to) - (loc) - 3))
+
+/* Likewise, for a two-argument jump.  */
+#define STORE_JUMP2(op, loc, to, arg) \
+  store_op2 (op, loc, (int) ((to) - (loc) - 3), arg)
+
+/* Like `STORE_JUMP', but for inserting.  Assume `b' is the buffer end.  */
+#define INSERT_JUMP(op, loc, to) \
+  insert_op1 (op, loc, (int) ((to) - (loc) - 3), b)
+
+/* Like `STORE_JUMP2', but for inserting.  Assume `b' is the buffer end.  */
+#define INSERT_JUMP2(op, loc, to, arg) \
+  insert_op2 (op, loc, (int) ((to) - (loc) - 3), arg, b)
+
+
+/* This is not an arbitrary limit: the arguments which represent offsets
+   into the pattern are two bytes long.  So if 2^16 bytes turns out to
+   be too small, many things would have to change.  */
+/* Any other compiler which, like MSC, has allocation limit below 2^16
+   bytes will have to use approach similar to what was done below for
+   MSC and drop MAX_BUF_SIZE a bit.  Otherwise you may end up
+   reallocating to 0 bytes.  Such thing is not going to work too well.
+   You have been warned!!  */
+#if defined _MSC_VER  && !defined WIN32
+/* Microsoft C 16-bit versions limit malloc to approx 65512 bytes.
+   The REALLOC define eliminates a flurry of conversion warnings,
+   but is not required. */
+# define MAX_BUF_SIZE  65500L
+# define REALLOC(p,s) realloc ((p), (size_t) (s))
+#else
+# define MAX_BUF_SIZE (1L << 16)
+# define REALLOC(p,s) realloc ((p), (s))
+#endif
+
+/* Extend the buffer by twice its current size via realloc and
+   reset the pointers that pointed into the old block to point to the
+   correct places in the new one.  If extending the buffer results in it
+   being larger than MAX_BUF_SIZE, then flag memory exhausted.  */
+#define EXTEND_BUFFER()							\
+  do { 									\
+    unsigned char *old_buffer = bufp->buffer;				\
+    if (bufp->allocated == MAX_BUF_SIZE) 				\
+      return REG_ESIZE;							\
+    bufp->allocated <<= 1;						\
+    if (bufp->allocated > MAX_BUF_SIZE)					\
+      bufp->allocated = MAX_BUF_SIZE; 					\
+    bufp->buffer = (unsigned char *) REALLOC (bufp->buffer, bufp->allocated);\
+    if (bufp->buffer == NULL)						\
+      return REG_ESPACE;						\
+    /* If the buffer moved, move all the pointers into it.  */		\
+    if (old_buffer != bufp->buffer)					\
+      {									\
+        b = (b - old_buffer) + bufp->buffer;				\
+        begalt = (begalt - old_buffer) + bufp->buffer;			\
+        if (fixup_alt_jump)						\
+          fixup_alt_jump = (fixup_alt_jump - old_buffer) + bufp->buffer;\
+        if (laststart)							\
+          laststart = (laststart - old_buffer) + bufp->buffer;		\
+        if (pending_exact)						\
+          pending_exact = (pending_exact - old_buffer) + bufp->buffer;	\
+      }									\
+  } while (0)
+
+
+/* Since we have one byte reserved for the register number argument to
+   {start,stop}_memory, the maximum number of groups we can report
+   things about is what fits in that byte.  */
+#define MAX_REGNUM 255
+
+/* But patterns can have more than `MAX_REGNUM' registers.  We just
+   ignore the excess.  */
+typedef unsigned regnum_t;
+
+
+/* Macros for the compile stack.  */
+
+/* Since offsets can go either forwards or backwards, this type needs to
+   be able to hold values from -(MAX_BUF_SIZE - 1) to MAX_BUF_SIZE - 1.  */
+/* int may be not enough when sizeof(int) == 2.  */
+typedef long pattern_offset_t;
+
+typedef struct {
+	pattern_offset_t begalt_offset;
+	pattern_offset_t fixup_alt_jump;
+	pattern_offset_t inner_group_offset;
+	pattern_offset_t laststart_offset;
+	regnum_t regnum;
+} compile_stack_elt_t;
+
+
+typedef struct {
+	compile_stack_elt_t *stack;
+	unsigned size;
+	unsigned avail;				/* Offset of next open position.  */
+} compile_stack_type;
+
+
+#define INIT_COMPILE_STACK_SIZE 32
+
+#define COMPILE_STACK_EMPTY  (compile_stack.avail == 0)
+#define COMPILE_STACK_FULL  (compile_stack.avail == compile_stack.size)
+
+/* The next available element.  */
+#define COMPILE_STACK_TOP (compile_stack.stack[compile_stack.avail])
+
+
+/* Set the bit for character C in a list.  */
+#define SET_LIST_BIT(c)                               \
+  (b[((unsigned char) (c)) / BYTEWIDTH]               \
+   |= 1 << (((unsigned char) c) % BYTEWIDTH))
+
+
+/* Get the next unsigned number in the uncompiled pattern.  */
+#define GET_UNSIGNED_NUMBER(num) 					\
+  { if (p != pend)							\
+     {									\
+       PATFETCH (c); 							\
+       while ('0' <= c && c <= '9')					\
+         { 								\
+           if (num < 0)							\
+              num = 0;							\
+           num = num * 10 + c - '0'; 					\
+           if (p == pend) 						\
+              break; 							\
+           PATFETCH (c);						\
+         } 								\
+       } 								\
+    }
+
+#if defined _LIBC || WIDE_CHAR_SUPPORT
+/* The GNU C library provides support for user-defined character classes
+   and the functions from ISO C amendement 1.  */
+# ifdef CHARCLASS_NAME_MAX
+#  define CHAR_CLASS_MAX_LENGTH CHARCLASS_NAME_MAX
+# else
+/* This shouldn't happen but some implementation might still have this
+   problem.  Use a reasonable default value.  */
+#  define CHAR_CLASS_MAX_LENGTH 256
+# endif
+
+# ifdef _LIBC
+#  define IS_CHAR_CLASS(string) __wctype (string)
+# else
+#  define IS_CHAR_CLASS(string) wctype (string)
+# endif
+#else
+# define CHAR_CLASS_MAX_LENGTH  6	/* Namely, `xdigit'.  */
+
+# define IS_CHAR_CLASS(string)						\
+   (STREQ (string, "alpha") || STREQ (string, "upper")			\
+    || STREQ (string, "lower") || STREQ (string, "digit")		\
+    || STREQ (string, "alnum") || STREQ (string, "xdigit")		\
+    || STREQ (string, "space") || STREQ (string, "print")		\
+    || STREQ (string, "punct") || STREQ (string, "graph")		\
+    || STREQ (string, "cntrl") || STREQ (string, "blank"))
+#endif
+
+#ifndef MATCH_MAY_ALLOCATE
+
+/* If we cannot allocate large objects within re_match_2_internal,
+   we make the fail stack and register vectors global.
+   The fail stack, we grow to the maximum size when a regexp
+   is compiled.
+   The register vectors, we adjust in size each time we
+   compile a regexp, according to the number of registers it needs.  */
+
+static fail_stack_type fail_stack;
+
+/* Size with which the following vectors are currently allocated.
+   That is so we can make them bigger as needed,
+   but never make them smaller.  */
+static int regs_allocated_size;
+
+static const char **regstart, **regend;
+static const char **old_regstart, **old_regend;
+static const char **best_regstart, **best_regend;
+static register_info_type *reg_info;
+static const char **reg_dummy;
+static register_info_type *reg_info_dummy;
+
+/* Make the register vectors big enough for NUM_REGS registers,
+   but don't make them smaller.  */
+
+static regex_grow_registers(num_regs)
+int num_regs;
+{
+	if (num_regs > regs_allocated_size) {
+		RETALLOC_IF(regstart, num_regs, const char *);
+		RETALLOC_IF(regend, num_regs, const char *);
+		RETALLOC_IF(old_regstart, num_regs, const char *);
+		RETALLOC_IF(old_regend, num_regs, const char *);
+		RETALLOC_IF(best_regstart, num_regs, const char *);
+		RETALLOC_IF(best_regend, num_regs, const char *);
+
+		RETALLOC_IF(reg_info, num_regs, register_info_type);
+		RETALLOC_IF(reg_dummy, num_regs, const char *);
+
+		RETALLOC_IF(reg_info_dummy, num_regs, register_info_type);
+
+		regs_allocated_size = num_regs;
+	}
+}
+
+#endif							/* not MATCH_MAY_ALLOCATE */
+
+static boolean group_in_compile_stack _RE_ARGS((compile_stack_type
+												compile_stack,
+
+												regnum_t regnum));
+
+/* `regex_compile' compiles PATTERN (of length SIZE) according to SYNTAX.
+   Returns one of error codes defined in `regex.h', or zero for success.
+
+   Assumes the `allocated' (and perhaps `buffer') and `translate'
+   fields are set in BUFP on entry.
+
+   If it succeeds, results are put in BUFP (if it returns an error, the
+   contents of BUFP are undefined):
+     `buffer' is the compiled pattern;
+     `syntax' is set to SYNTAX;
+     `used' is set to the length of the compiled pattern;
+     `fastmap_accurate' is zero;
+     `re_nsub' is the number of subexpressions in PATTERN;
+     `not_bol' and `not_eol' are zero;
+
+   The `fastmap' and `newline_anchor' fields are neither
+   examined nor set.  */
+
+/* Return, freeing storage we allocated.  */
+#define FREE_STACK_RETURN(value)		\
+  return (free (compile_stack.stack), value)
+
+static reg_errcode_t regex_compile(pattern, size, syntax, bufp)
+const char *pattern;
+size_t size;
+reg_syntax_t syntax;
+struct re_pattern_buffer *bufp;
+{
+	/* We fetch characters from PATTERN here.  Even though PATTERN is
+	   `char *' (i.e., signed), we declare these variables as unsigned, so
+	   they can be reliably used as array indices.  */
+	register unsigned char c, c1;
+
+	/* A random temporary spot in PATTERN.  */
+	const char *p1;
+
+	/* Points to the end of the buffer, where we should append.  */
+	register unsigned char *b;
+
+	/* Keeps track of unclosed groups.  */
+	compile_stack_type compile_stack;
+
+	/* Points to the current (ending) position in the pattern.  */
+	const char *p = pattern;
+	const char *pend = pattern + size;
+
+	/* How to translate the characters in the pattern.  */
+	RE_TRANSLATE_TYPE translate = bufp->translate;
+
+	/* Address of the count-byte of the most recently inserted `exactn'
+	   command.  This makes it possible to tell if a new exact-match
+	   character can be added to that command or if the character requires
+	   a new `exactn' command.  */
+	unsigned char *pending_exact = 0;
+
+	/* Address of start of the most recently finished expression.
+	   This tells, e.g., postfix * where to find the start of its
+	   operand.  Reset at the beginning of groups and alternatives.  */
+	unsigned char *laststart = 0;
+
+	/* Address of beginning of regexp, or inside of last group.  */
+	unsigned char *begalt;
+
+	/* Place in the uncompiled pattern (i.e., the {) to
+	   which to go back if the interval is invalid.  */
+	const char *beg_interval;
+
+	/* Address of the place where a forward jump should go to the end of
+	   the containing expression.  Each alternative of an `or' -- except the
+	   last -- ends with a forward jump of this sort.  */
+	unsigned char *fixup_alt_jump = 0;
+
+	/* Counts open-groups as they are encountered.  Remembered for the
+	   matching close-group on the compile stack, so the same register
+	   number is put in the stop_memory as the start_memory.  */
+	regnum_t regnum = 0;
+
+#ifdef DEBUG
+	DEBUG_PRINT1("\nCompiling pattern: ");
+	if (debug) {
+		unsigned debug_count;
+
+		for (debug_count = 0; debug_count < size; debug_count++)
+			putchar(pattern[debug_count]);
+		putchar('\n');
+	}
+#endif							/* DEBUG */
+
+	/* Initialize the compile stack.  */
+	compile_stack.stack =
+		TALLOC(INIT_COMPILE_STACK_SIZE, compile_stack_elt_t);
+	if (compile_stack.stack == NULL)
+		return REG_ESPACE;
+
+	compile_stack.size = INIT_COMPILE_STACK_SIZE;
+	compile_stack.avail = 0;
+
+	/* Initialize the pattern buffer.  */
+	bufp->syntax = syntax;
+	bufp->fastmap_accurate = 0;
+	bufp->not_bol = bufp->not_eol = 0;
+
+	/* Set `used' to zero, so that if we return an error, the pattern
+	   printer (for debugging) will think there's no pattern.  We reset it
+	   at the end.  */
+	bufp->used = 0;
+
+	/* Always count groups, whether or not bufp->no_sub is set.  */
+	bufp->re_nsub = 0;
+
+#if !defined emacs && !defined SYNTAX_TABLE
+	/* Initialize the syntax table.  */
+	init_syntax_once();
+#endif
+
+	if (bufp->allocated == 0) {
+		if (bufp->buffer) {		/* If zero allocated, but buffer is non-null, try to realloc
+								   enough space.  This loses if buffer's address is bogus, but
+								   that is the user's responsibility.  */
+			RETALLOC(bufp->buffer, INIT_BUF_SIZE, unsigned char);
+		} else {				/* Caller did not allocate a buffer.  Do it for them.  */
+			bufp->buffer = TALLOC(INIT_BUF_SIZE, unsigned char);
+		}
+		if (!bufp->buffer)
+			FREE_STACK_RETURN(REG_ESPACE);
+
+		bufp->allocated = INIT_BUF_SIZE;
+	}
+
+	begalt = b = bufp->buffer;
+
+	/* Loop through the uncompiled pattern until we're at the end.  */
+	while (p != pend) {
+		PATFETCH(c);
+
+		switch (c) {
+		case '^':
+		{
+			if (				/* If at start of pattern, it's an operator.  */
+				   p == pattern + 1
+				   /* If context independent, it's an operator.  */
+				   || syntax & RE_CONTEXT_INDEP_ANCHORS
+				   /* Otherwise, depends on what's come before.  */
+				   || at_begline_loc_p(pattern, p, syntax))
+				BUF_PUSH(begline);
+			else
+				goto normal_char;
+		}
+			break;
+
+
+		case '$':
+		{
+			if (				/* If at end of pattern, it's an operator.  */
+				   p == pend
+				   /* If context independent, it's an operator.  */
+				   || syntax & RE_CONTEXT_INDEP_ANCHORS
+				   /* Otherwise, depends on what's next.  */
+				   || at_endline_loc_p(p, pend, syntax))
+				BUF_PUSH(endline);
+			else
+				goto normal_char;
+		}
+			break;
+
+
+		case '+':
+		case '?':
+			if ((syntax & RE_BK_PLUS_QM)
+				|| (syntax & RE_LIMITED_OPS))
+				goto normal_char;
+		  handle_plus:
+		case '*':
+			/* If there is no previous pattern... */
+			if (!laststart) {
+				if (syntax & RE_CONTEXT_INVALID_OPS)
+					FREE_STACK_RETURN(REG_BADRPT);
+				else if (!(syntax & RE_CONTEXT_INDEP_OPS))
+					goto normal_char;
+			}
+
+			{
+				/* Are we optimizing this jump?  */
+				boolean keep_string_p = false;
+
+				/* 1 means zero (many) matches is allowed.  */
+				char zero_times_ok = 0, many_times_ok = 0;
+
+				/* If there is a sequence of repetition chars, collapse it
+				   down to just one (the right one).  We can't combine
+				   interval operators with these because of, e.g., `a{2}*',
+				   which should only match an even number of `a's.  */
+
+				for (;;) {
+					zero_times_ok |= c != '+';
+					many_times_ok |= c != '?';
+
+					if (p == pend)
+						break;
+
+					PATFETCH(c);
+
+					if (c == '*'
+						|| (!(syntax & RE_BK_PLUS_QM)
+							&& (c == '+' || c == '?')));
+
+					else if (syntax & RE_BK_PLUS_QM && c == '\\') {
+						if (p == pend)
+							FREE_STACK_RETURN(REG_EESCAPE);
+
+						PATFETCH(c1);
+						if (!(c1 == '+' || c1 == '?')) {
+							PATUNFETCH;
+							PATUNFETCH;
+							break;
+						}
+
+						c = c1;
+					} else {
+						PATUNFETCH;
+						break;
+					}
+
+					/* If we get here, we found another repeat character.  */
+				}
+
+				/* Star, etc. applied to an empty pattern is equivalent
+				   to an empty pattern.  */
+				if (!laststart)
+					break;
+
+				/* Now we know whether or not zero matches is allowed
+				   and also whether or not two or more matches is allowed.  */
+				if (many_times_ok) {	/* More than one repetition is allowed, so put in at the
+										   end a backward relative jump from `b' to before the next
+										   jump we're going to put in below (which jumps from
+										   laststart to after this jump).
+
+										   But if we are at the `*' in the exact sequence `.*\n',
+										   insert an unconditional jump backwards to the .,
+										   instead of the beginning of the loop.  This way we only
+										   push a failure point once, instead of every time
+										   through the loop.  */
+					assert(p - 1 > pattern);
+
+					/* Allocate the space for the jump.  */
+					GET_BUFFER_SPACE(3);
+
+					/* We know we are not at the first character of the pattern,
+					   because laststart was nonzero.  And we've already
+					   incremented `p', by the way, to be the character after
+					   the `*'.  Do we have to do something analogous here
+					   for null bytes, because of RE_DOT_NOT_NULL?  */
+					if (TRANSLATE(*(p - 2)) == TRANSLATE('.')
+						&& zero_times_ok
+						&& p < pend && TRANSLATE(*p) == TRANSLATE('\n')
+						&& !(syntax & RE_DOT_NEWLINE)) {	/* We have .*\n.  */
+						STORE_JUMP(jump, b, laststart);
+						keep_string_p = true;
+					} else
+						/* Anything else.  */
+						STORE_JUMP(maybe_pop_jump, b, laststart - 3);
+
+					/* We've added more stuff to the buffer.  */
+					b += 3;
+				}
+
+				/* On failure, jump from laststart to b + 3, which will be the
+				   end of the buffer after this jump is inserted.  */
+				GET_BUFFER_SPACE(3);
+				INSERT_JUMP(keep_string_p ? on_failure_keep_string_jump
+							: on_failure_jump, laststart, b + 3);
+				pending_exact = 0;
+				b += 3;
+
+				if (!zero_times_ok) {
+					/* At least one repetition is required, so insert a
+					   `dummy_failure_jump' before the initial
+					   `on_failure_jump' instruction of the loop. This
+					   effects a skip over that instruction the first time
+					   we hit that loop.  */
+					GET_BUFFER_SPACE(3);
+					INSERT_JUMP(dummy_failure_jump, laststart,
+								laststart + 6);
+					b += 3;
+				}
+			}
+			break;
+
+
+		case '.':
+			laststart = b;
+			BUF_PUSH(anychar);
+			break;
+
+
+		case '[':
+		{
+			boolean had_char_class = false;
+
+			if (p == pend)
+				FREE_STACK_RETURN(REG_EBRACK);
+
+			/* Ensure that we have enough space to push a charset: the
+			   opcode, the length count, and the bitset; 34 bytes in all.  */
+			GET_BUFFER_SPACE(34);
+
+			laststart = b;
+
+			/* We test `*p == '^' twice, instead of using an if
+			   statement, so we only need one BUF_PUSH.  */
+			BUF_PUSH(*p == '^' ? charset_not : charset);
+			if (*p == '^')
+				p++;
+
+			/* Remember the first position in the bracket expression.  */
+			p1 = p;
+
+			/* Push the number of bytes in the bitmap.  */
+			BUF_PUSH((1 << BYTEWIDTH) / BYTEWIDTH);
+
+			/* Clear the whole map.  */
+			bzero(b, (1 << BYTEWIDTH) / BYTEWIDTH);
+
+			/* charset_not matches newline according to a syntax bit.  */
+			if ((re_opcode_t) b[-2] == charset_not
+				&& (syntax & RE_HAT_LISTS_NOT_NEWLINE)) SET_LIST_BIT('\n');
+
+			/* Read in characters and ranges, setting map bits.  */
+			for (;;) {
+				if (p == pend)
+					FREE_STACK_RETURN(REG_EBRACK);
+
+				PATFETCH(c);
+
+				/* \ might escape characters inside [...] and [^...].  */
+				if ((syntax & RE_BACKSLASH_ESCAPE_IN_LISTS) && c == '\\') {
+					if (p == pend)
+						FREE_STACK_RETURN(REG_EESCAPE);
+
+					PATFETCH(c1);
+					SET_LIST_BIT(c1);
+					continue;
+				}
+
+				/* Could be the end of the bracket expression.  If it's
+				   not (i.e., when the bracket expression is `[]' so
+				   far), the ']' character bit gets set way below.  */
+				if (c == ']' && p != p1 + 1)
+					break;
+
+				/* Look ahead to see if it's a range when the last thing
+				   was a character class.  */
+				if (had_char_class && c == '-' && *p != ']')
+					FREE_STACK_RETURN(REG_ERANGE);
+
+				/* Look ahead to see if it's a range when the last thing
+				   was a character: if this is a hyphen not at the
+				   beginning or the end of a list, then it's the range
+				   operator.  */
+				if (c == '-' && !(p - 2 >= pattern && p[-2] == '[')
+					&& !(p - 3 >= pattern && p[-3] == '[' && p[-2] == '^')
+					&& *p != ']') {
+					reg_errcode_t ret
+						= compile_range(&p, pend, translate, syntax, b);
+
+					if (ret != REG_NOERROR)
+						FREE_STACK_RETURN(ret);
+				}
+
+				else if (p[0] == '-' && p[1] != ']') {	/* This handles ranges made up of characters only.  */
+					reg_errcode_t ret;
+
+					/* Move past the `-'.  */
+					PATFETCH(c1);
+
+					ret = compile_range(&p, pend, translate, syntax, b);
+					if (ret != REG_NOERROR)
+						FREE_STACK_RETURN(ret);
+				}
+
+				/* See if we're at the beginning of a possible character
+				   class.  */
+
+				else if (syntax & RE_CHAR_CLASSES && c == '[' && *p == ':') {	/* Leave room for the null.  */
+					char str[CHAR_CLASS_MAX_LENGTH + 1];
+
+					PATFETCH(c);
+					c1 = 0;
+
+					/* If pattern is `[[:'.  */
+					if (p == pend)
+						FREE_STACK_RETURN(REG_EBRACK);
+
+					for (;;) {
+						PATFETCH(c);
+						if ((c == ':' && *p == ']') || p == pend)
+							break;
+						if (c1 < CHAR_CLASS_MAX_LENGTH)
+							str[c1++] = c;
+						else
+							/* This is in any case an invalid class name.  */
+							str[0] = '\0';
+					}
+					str[c1] = '\0';
+
+					/* If isn't a word bracketed by `[:' and `:]':
+					   undo the ending character, the letters, and leave
+					   the leading `:' and `[' (but set bits for them).  */
+					if (c == ':' && *p == ']') {
+#if defined _LIBC || WIDE_CHAR_SUPPORT
+						boolean is_lower = STREQ(str, "lower");
+						boolean is_upper = STREQ(str, "upper");
+						wctype_t wt;
+						int ch;
+
+						wt = IS_CHAR_CLASS(str);
+						if (wt == 0)
+							FREE_STACK_RETURN(REG_ECTYPE);
+
+						/* Throw away the ] at the end of the character
+						   class.  */
+						PATFETCH(c);
+
+						if (p == pend)
+							FREE_STACK_RETURN(REG_EBRACK);
+
+						for (ch = 0; ch < 1 << BYTEWIDTH; ++ch) {
+# ifdef _LIBC
+							if (__iswctype(__btowc(ch), wt))
+								SET_LIST_BIT(ch);
+# else
+							if (iswctype(btowc(ch), wt))
+								SET_LIST_BIT(ch);
+# endif
+
+							if (translate && (is_upper || is_lower)
+								&& (ISUPPER(ch) || ISLOWER(ch)))
+								SET_LIST_BIT(ch);
+						}
+
+						had_char_class = true;
+#else
+						int ch;
+						boolean is_alnum = STREQ(str, "alnum");
+						boolean is_alpha = STREQ(str, "alpha");
+						boolean is_blank = STREQ(str, "blank");
+						boolean is_cntrl = STREQ(str, "cntrl");
+						boolean is_digit = STREQ(str, "digit");
+						boolean is_graph = STREQ(str, "graph");
+						boolean is_lower = STREQ(str, "lower");
+						boolean is_print = STREQ(str, "print");
+						boolean is_punct = STREQ(str, "punct");
+						boolean is_space = STREQ(str, "space");
+						boolean is_upper = STREQ(str, "upper");
+						boolean is_xdigit = STREQ(str, "xdigit");
+
+						if (!IS_CHAR_CLASS(str))
+							FREE_STACK_RETURN(REG_ECTYPE);
+
+						/* Throw away the ] at the end of the character
+						   class.  */
+						PATFETCH(c);
+
+						if (p == pend)
+							FREE_STACK_RETURN(REG_EBRACK);
+
+						for (ch = 0; ch < 1 << BYTEWIDTH; ch++) {
+							/* This was split into 3 if's to
+							   avoid an arbitrary limit in some compiler.  */
+							if ((is_alnum && ISALNUM(ch))
+								|| (is_alpha && ISALPHA(ch))
+								|| (is_blank && ISBLANK(ch))
+								|| (is_cntrl && ISCNTRL(ch)))
+								SET_LIST_BIT(ch);
+							if ((is_digit && ISDIGIT(ch))
+								|| (is_graph && ISGRAPH(ch))
+								|| (is_lower && ISLOWER(ch))
+								|| (is_print && ISPRINT(ch)))
+								SET_LIST_BIT(ch);
+							if ((is_punct && ISPUNCT(ch))
+								|| (is_space && ISSPACE(ch))
+								|| (is_upper && ISUPPER(ch))
+								|| (is_xdigit && ISXDIGIT(ch)))
+								SET_LIST_BIT(ch);
+							if (translate && (is_upper || is_lower)
+								&& (ISUPPER(ch) || ISLOWER(ch)))
+								SET_LIST_BIT(ch);
+						}
+						had_char_class = true;
+#endif							/* libc || wctype.h */
+					} else {
+						c1++;
+						while (c1--)
+							PATUNFETCH;
+						SET_LIST_BIT('[');
+						SET_LIST_BIT(':');
+						had_char_class = false;
+					}
+				} else {
+					had_char_class = false;
+					SET_LIST_BIT(c);
+				}
+			}
+
+			/* Discard any (non)matching list bytes that are all 0 at the
+			   end of the map.  Decrease the map-length byte too.  */
+			while ((int) b[-1] > 0 && b[b[-1] - 1] == 0)
+				b[-1]--;
+			b += b[-1];
+		}
+			break;
+
+
+		case '(':
+			if (syntax & RE_NO_BK_PARENS)
+				goto handle_open;
+			else
+				goto normal_char;
+
+
+		case ')':
+			if (syntax & RE_NO_BK_PARENS)
+				goto handle_close;
+			else
+				goto normal_char;
+
+
+		case '\n':
+			if (syntax & RE_NEWLINE_ALT)
+				goto handle_alt;
+			else
+				goto normal_char;
+
+
+		case '|':
+			if (syntax & RE_NO_BK_VBAR)
+				goto handle_alt;
+			else
+				goto normal_char;
+
+
+		case '{':
+			if (syntax & RE_INTERVALS && syntax & RE_NO_BK_BRACES)
+				goto handle_interval;
+			else
+				goto normal_char;
+
+
+		case '\\':
+			if (p == pend)
+				FREE_STACK_RETURN(REG_EESCAPE);
+
+			/* Do not translate the character after the \, so that we can
+			   distinguish, e.g., \B from \b, even if we normally would
+			   translate, e.g., B to b.  */
+			PATFETCH_RAW(c);
+
+			switch (c) {
+			case '(':
+				if (syntax & RE_NO_BK_PARENS)
+					goto normal_backslash;
+
+			  handle_open:
+				bufp->re_nsub++;
+				regnum++;
+
+				if (COMPILE_STACK_FULL) {
+					RETALLOC(compile_stack.stack, compile_stack.size << 1,
+							 compile_stack_elt_t);
+					if (compile_stack.stack == NULL)
+						return REG_ESPACE;
+
+					compile_stack.size <<= 1;
+				}
+
+				/* These are the values to restore when we hit end of this
+				   group.  They are all relative offsets, so that if the
+				   whole pattern moves because of realloc, they will still
+				   be valid.  */
+				COMPILE_STACK_TOP.begalt_offset = begalt - bufp->buffer;
+				COMPILE_STACK_TOP.fixup_alt_jump
+					=
+					fixup_alt_jump ? fixup_alt_jump - bufp->buffer + 1 : 0;
+				COMPILE_STACK_TOP.laststart_offset = b - bufp->buffer;
+				COMPILE_STACK_TOP.regnum = regnum;
+
+				/* We will eventually replace the 0 with the number of
+				   groups inner to this one.  But do not push a
+				   start_memory for groups beyond the last one we can
+				   represent in the compiled pattern.  */
+				if (regnum <= MAX_REGNUM) {
+					COMPILE_STACK_TOP.inner_group_offset =
+						b - bufp->buffer + 2;
+					BUF_PUSH_3(start_memory, regnum, 0);
+				}
+
+				compile_stack.avail++;
+
+				fixup_alt_jump = 0;
+				laststart = 0;
+				begalt = b;
+				/* If we've reached MAX_REGNUM groups, then this open
+				   won't actually generate any code, so we'll have to
+				   clear pending_exact explicitly.  */
+				pending_exact = 0;
+				break;
+
+
+			case ')':
+				if (syntax & RE_NO_BK_PARENS)
+					goto normal_backslash;
+
+				if (COMPILE_STACK_EMPTY) {
+					if (syntax & RE_UNMATCHED_RIGHT_PAREN_ORD)
+						goto normal_backslash;
+					else
+						FREE_STACK_RETURN(REG_ERPAREN);
+				}
+
+			  handle_close:
+				if (fixup_alt_jump) {	/* Push a dummy failure point at the end of the
+										   alternative for a possible future
+										   `pop_failure_jump' to pop.  See comments at
+										   `push_dummy_failure' in `re_match_2'.  */
+					BUF_PUSH(push_dummy_failure);
+
+					/* We allocated space for this jump when we assigned
+					   to `fixup_alt_jump', in the `handle_alt' case below.  */
+					STORE_JUMP(jump_past_alt, fixup_alt_jump, b - 1);
+				}
+
+				/* See similar code for backslashed left paren above.  */
+				if (COMPILE_STACK_EMPTY) {
+					if (syntax & RE_UNMATCHED_RIGHT_PAREN_ORD)
+						goto normal_char;
+					else
+						FREE_STACK_RETURN(REG_ERPAREN);
+				}
+
+				/* Since we just checked for an empty stack above, this
+				   ``can't happen''.  */
+				assert(compile_stack.avail != 0);
+				{
+					/* We don't just want to restore into `regnum', because
+					   later groups should continue to be numbered higher,
+					   as in `(ab)c(de)' -- the second group is #2.  */
+					regnum_t this_group_regnum;
+
+					compile_stack.avail--;
+					begalt =
+						bufp->buffer + COMPILE_STACK_TOP.begalt_offset;
+					fixup_alt_jump =
+						COMPILE_STACK_TOP.fixup_alt_jump ? bufp->buffer +
+						COMPILE_STACK_TOP.fixup_alt_jump - 1 : 0;
+					laststart =
+						bufp->buffer + COMPILE_STACK_TOP.laststart_offset;
+					this_group_regnum = COMPILE_STACK_TOP.regnum;
+					/* If we've reached MAX_REGNUM groups, then this open
+					   won't actually generate any code, so we'll have to
+					   clear pending_exact explicitly.  */
+					pending_exact = 0;
+
+					/* We're at the end of the group, so now we know how many
+					   groups were inside this one.  */
+					if (this_group_regnum <= MAX_REGNUM) {
+						unsigned char *inner_group_loc
+
+							=
+							bufp->buffer +
+							COMPILE_STACK_TOP.inner_group_offset;
+
+						*inner_group_loc = regnum - this_group_regnum;
+						BUF_PUSH_3(stop_memory, this_group_regnum,
+								   regnum - this_group_regnum);
+					}
+				}
+				break;
+
+
+			case '|':			/* `\|'.  */
+				if (syntax & RE_LIMITED_OPS || syntax & RE_NO_BK_VBAR)
+					goto normal_backslash;
+			  handle_alt:
+				if (syntax & RE_LIMITED_OPS)
+					goto normal_char;
+
+				/* Insert before the previous alternative a jump which
+				   jumps to this alternative if the former fails.  */
+				GET_BUFFER_SPACE(3);
+				INSERT_JUMP(on_failure_jump, begalt, b + 6);
+				pending_exact = 0;
+				b += 3;
+
+				/* The alternative before this one has a jump after it
+				   which gets executed if it gets matched.  Adjust that
+				   jump so it will jump to this alternative's analogous
+				   jump (put in below, which in turn will jump to the next
+				   (if any) alternative's such jump, etc.).  The last such
+				   jump jumps to the correct final destination.  A picture:
+				   _____ _____
+				   |   | |   |
+				   |   v |   v
+				   a | b   | c
+
+				   If we are at `b', then fixup_alt_jump right now points to a
+				   three-byte space after `a'.  We'll put in the jump, set
+				   fixup_alt_jump to right after `b', and leave behind three
+				   bytes which we'll fill in when we get to after `c'.  */
+
+				if (fixup_alt_jump)
+					STORE_JUMP(jump_past_alt, fixup_alt_jump, b);
+
+				/* Mark and leave space for a jump after this alternative,
+				   to be filled in later either by next alternative or
+				   when know we're at the end of a series of alternatives.  */
+				fixup_alt_jump = b;
+				GET_BUFFER_SPACE(3);
+				b += 3;
+
+				laststart = 0;
+				begalt = b;
+				break;
+
+
+			case '{':
+				/* If \{ is a literal.  */
+				if (!(syntax & RE_INTERVALS)
+					/* If we're at `\{' and it's not the open-interval
+					   operator.  */
+					|| ((syntax & RE_INTERVALS)
+						&& (syntax & RE_NO_BK_BRACES)) || (p - 2 == pattern
+														   && p == pend))
+					goto normal_backslash;
+
+			  handle_interval:
+				{
+					/* If got here, then the syntax allows intervals.  */
+
+					/* At least (most) this many matches must be made.  */
+					int lower_bound = -1, upper_bound = -1;
+
+					beg_interval = p - 1;
+
+					if (p == pend) {
+						if (!(syntax & RE_INTERVALS)
+							&& (syntax & RE_NO_BK_BRACES)) goto
+								unfetch_interval;
+						else
+							FREE_STACK_RETURN(REG_EBRACE);
+					}
+
+					GET_UNSIGNED_NUMBER(lower_bound);
+
+					if (c == ',') {
+						GET_UNSIGNED_NUMBER(upper_bound);
+						if ((!(syntax & RE_NO_BK_BRACES) && c != '\\')
+							|| ((syntax & RE_NO_BK_BRACES) && c != '}'))
+							FREE_STACK_RETURN(REG_BADBR);
+
+						if (upper_bound < 0)
+							upper_bound = RE_DUP_MAX;
+					} else
+						/* Interval such as `{1}' => match exactly once. */
+						upper_bound = lower_bound;
+
+					if (lower_bound < 0 || upper_bound > RE_DUP_MAX
+						|| lower_bound > upper_bound) {
+						if (!(syntax & RE_INTERVALS)
+							&& (syntax & RE_NO_BK_BRACES)) goto
+								unfetch_interval;
+						else
+							FREE_STACK_RETURN(REG_BADBR);
+					}
+
+					if (!(syntax & RE_NO_BK_BRACES)) {
+						if (c != '\\')
+							FREE_STACK_RETURN(REG_EBRACE);
+
+						PATFETCH(c);
+					}
+
+					if (c != '}') {
+						if (!(syntax & RE_INTERVALS)
+							&& (syntax & RE_NO_BK_BRACES)) goto
+								unfetch_interval;
+						else
+							FREE_STACK_RETURN(REG_BADBR);
+					}
+
+					/* We just parsed a valid interval.  */
+
+					/* If it's invalid to have no preceding re.  */
+					if (!laststart) {
+						if (syntax & RE_CONTEXT_INVALID_OPS)
+							FREE_STACK_RETURN(REG_BADRPT);
+						else if (syntax & RE_CONTEXT_INDEP_OPS)
+							laststart = b;
+						else
+							goto unfetch_interval;
+					}
+
+					/* If the upper bound is zero, don't want to succeed at
+					   all; jump from `laststart' to `b + 3', which will be
+					   the end of the buffer after we insert the jump.  */
+					if (upper_bound == 0) {
+						GET_BUFFER_SPACE(3);
+						INSERT_JUMP(jump, laststart, b + 3);
+						b += 3;
+					}
+
+					/* Otherwise, we have a nontrivial interval.  When
+					   we're all done, the pattern will look like:
+					   set_number_at <jump count> <upper bound>
+					   set_number_at <succeed_n count> <lower bound>
+					   succeed_n <after jump addr> <succeed_n count>
+					   <body of loop>
+					   jump_n <succeed_n addr> <jump count>
+					   (The upper bound and `jump_n' are omitted if
+					   `upper_bound' is 1, though.)  */
+					else {		/* If the upper bound is > 1, we need to insert
+								   more at the end of the loop.  */
+						unsigned nbytes = 10 + (upper_bound > 1) * 10;
+
+						GET_BUFFER_SPACE(nbytes);
+
+						/* Initialize lower bound of the `succeed_n', even
+						   though it will be set during matching by its
+						   attendant `set_number_at' (inserted next),
+						   because `re_compile_fastmap' needs to know.
+						   Jump to the `jump_n' we might insert below.  */
+						INSERT_JUMP2(succeed_n, laststart,
+									 b + 5 + (upper_bound > 1) * 5,
+									 lower_bound);
+						b += 5;
+
+						/* Code to initialize the lower bound.  Insert
+						   before the `succeed_n'.  The `5' is the last two
+						   bytes of this `set_number_at', plus 3 bytes of
+						   the following `succeed_n'.  */
+						insert_op2(set_number_at, laststart, 5,
+								   lower_bound, b);
+						b += 5;
+
+						if (upper_bound > 1) {	/* More than one repetition is allowed, so
+												   append a backward jump to the `succeed_n'
+												   that starts this interval.
+
+												   When we've reached this during matching,
+												   we'll have matched the interval once, so
+												   jump back only `upper_bound - 1' times.  */
+							STORE_JUMP2(jump_n, b, laststart + 5,
+										upper_bound - 1);
+							b += 5;
+
+							/* The location we want to set is the second
+							   parameter of the `jump_n'; that is `b-2' as
+							   an absolute address.  `laststart' will be
+							   the `set_number_at' we're about to insert;
+							   `laststart+3' the number to set, the source
+							   for the relative address.  But we are
+							   inserting into the middle of the pattern --
+							   so everything is getting moved up by 5.
+							   Conclusion: (b - 2) - (laststart + 3) + 5,
+							   i.e., b - laststart.
+
+							   We insert this at the beginning of the loop
+							   so that if we fail during matching, we'll
+							   reinitialize the bounds.  */
+							insert_op2(set_number_at, laststart,
+									   b - laststart, upper_bound - 1, b);
+							b += 5;
+						}
+					}
+					pending_exact = 0;
+					beg_interval = NULL;
+				}
+				break;
+
+			  unfetch_interval:
+				/* If an invalid interval, match the characters as literals.  */
+				assert(beg_interval);
+				p = beg_interval;
+				beg_interval = NULL;
+
+				/* normal_char and normal_backslash need `c'.  */
+				PATFETCH(c);
+
+				if (!(syntax & RE_NO_BK_BRACES)) {
+					if (p > pattern && p[-1] == '\\')
+						goto normal_backslash;
+				}
+				goto normal_char;
+
+#ifdef emacs
+				/* There is no way to specify the before_dot and after_dot
+				   operators.  rms says this is ok.  --karl  */
+			case '=':
+				BUF_PUSH(at_dot);
+				break;
+
+			case 's':
+				laststart = b;
+				PATFETCH(c);
+				BUF_PUSH_2(syntaxspec, syntax_spec_code[c]);
+				break;
+
+			case 'S':
+				laststart = b;
+				PATFETCH(c);
+				BUF_PUSH_2(notsyntaxspec, syntax_spec_code[c]);
+				break;
+#endif							/* emacs */
+
+
+			case 'w':
+				if (syntax & RE_NO_GNU_OPS)
+					goto normal_char;
+				laststart = b;
+				BUF_PUSH(wordchar);
+				break;
+
+
+			case 'W':
+				if (syntax & RE_NO_GNU_OPS)
+					goto normal_char;
+				laststart = b;
+				BUF_PUSH(notwordchar);
+				break;
+
+
+			case '<':
+				if (syntax & RE_NO_GNU_OPS)
+					goto normal_char;
+				BUF_PUSH(wordbeg);
+				break;
+
+			case '>':
+				if (syntax & RE_NO_GNU_OPS)
+					goto normal_char;
+				BUF_PUSH(wordend);
+				break;
+
+			case 'b':
+				if (syntax & RE_NO_GNU_OPS)
+					goto normal_char;
+				BUF_PUSH(wordbound);
+				break;
+
+			case 'B':
+				if (syntax & RE_NO_GNU_OPS)
+					goto normal_char;
+				BUF_PUSH(notwordbound);
+				break;
+
+			case '`':
+				if (syntax & RE_NO_GNU_OPS)
+					goto normal_char;
+				BUF_PUSH(begbuf);
+				break;
+
+			case '\'':
+				if (syntax & RE_NO_GNU_OPS)
+					goto normal_char;
+				BUF_PUSH(endbuf);
+				break;
+
+			case '1':
+			case '2':
+			case '3':
+			case '4':
+			case '5':
+			case '6':
+			case '7':
+			case '8':
+			case '9':
+				if (syntax & RE_NO_BK_REFS)
+					goto normal_char;
+
+				c1 = c - '0';
+
+				if (c1 > regnum)
+					FREE_STACK_RETURN(REG_ESUBREG);
+
+				/* Can't back reference to a subexpression if inside of it.  */
+				if (group_in_compile_stack(compile_stack, (regnum_t) c1))
+					goto normal_char;
+
+				laststart = b;
+				BUF_PUSH_2(duplicate, c1);
+				break;
+
+
+			case '+':
+			case '?':
+				if (syntax & RE_BK_PLUS_QM)
+					goto handle_plus;
+				else
+					goto normal_backslash;
+
+			default:
+			  normal_backslash:
+				/* You might think it would be useful for \ to mean
+				   not to translate; but if we don't translate it
+				   it will never match anything.  */
+				c = TRANSLATE(c);
+				goto normal_char;
+			}
+			break;
+
+
+		default:
+			/* Expects the character in `c'.  */
+		  normal_char:
+			/* If no exactn currently being built.  */
+			if (!pending_exact
+				/* If last exactn not at current position.  */
+				|| pending_exact + *pending_exact + 1 != b
+				/* We have only one byte following the exactn for the count.  */
+				|| *pending_exact == (1 << BYTEWIDTH) - 1
+				/* If followed by a repetition operator.  */
+				|| *p == '*' || *p == '^' || ((syntax & RE_BK_PLUS_QM)
+											  ? *p == '\\' && (p[1] == '+'
+															   || p[1] ==
+															   '?') : (*p
+																	   ==
+																	   '+'
+																	   ||
+																	   *p
+																	   ==
+																	   '?'))
+				|| ((syntax & RE_INTERVALS)
+					&& ((syntax & RE_NO_BK_BRACES)
+						? *p == '{' : (p[0] == '\\' && p[1] == '{')))) {
+				/* Start building a new exactn.  */
+
+				laststart = b;
+
+				BUF_PUSH_2(exactn, 0);
+				pending_exact = b - 1;
+			}
+
+			BUF_PUSH(c);
+			(*pending_exact)++;
+			break;
+		}						/* switch (c) */
+	}							/* while p != pend */
+
+
+	/* Through the pattern now.  */
+
+	if (fixup_alt_jump)
+		STORE_JUMP(jump_past_alt, fixup_alt_jump, b);
+
+	if (!COMPILE_STACK_EMPTY)
+		FREE_STACK_RETURN(REG_EPAREN);
+
+	/* If we don't want backtracking, force success
+	   the first time we reach the end of the compiled pattern.  */
+	if (syntax & RE_NO_POSIX_BACKTRACKING)
+		BUF_PUSH(succeed);
+
+	free(compile_stack.stack);
+
+	/* We have succeeded; set the length of the buffer.  */
+	bufp->used = b - bufp->buffer;
+
+#ifdef DEBUG
+	if (debug) {
+		DEBUG_PRINT1("\nCompiled pattern: \n");
+		print_compiled_pattern(bufp);
+	}
+#endif							/* DEBUG */
+
+#ifndef MATCH_MAY_ALLOCATE
+	/* Initialize the failure stack to the largest possible stack.  This
+	   isn't necessary unless we're trying to avoid calling alloca in
+	   the search and match routines.  */
+	{
+		int num_regs = bufp->re_nsub + 1;
+
+		/* Since DOUBLE_FAIL_STACK refuses to double only if the current size
+		   is strictly greater than re_max_failures, the largest possible stack
+		   is 2 * re_max_failures failure points.  */
+		if (fail_stack.size < (2 * re_max_failures * MAX_FAILURE_ITEMS)) {
+			fail_stack.size = (2 * re_max_failures * MAX_FAILURE_ITEMS);
+
+# ifdef emacs
+			if (!fail_stack.stack)
+				fail_stack.stack
+					= (fail_stack_elt_t *) xmalloc(fail_stack.size
+												   *
+												   sizeof
+												   (fail_stack_elt_t));
+			else
+				fail_stack.stack =
+					(fail_stack_elt_t *) xrealloc(fail_stack.stack,
+												  (fail_stack.size *
+												   sizeof
+												   (fail_stack_elt_t)));
+# else							/* not emacs */
+			if (!fail_stack.stack)
+				fail_stack.stack
+					= (fail_stack_elt_t *) malloc(fail_stack.size
+												  *
+												  sizeof
+												  (fail_stack_elt_t));
+			else
+				fail_stack.stack =
+					(fail_stack_elt_t *) realloc(fail_stack.stack,
+												 (fail_stack.size *
+												  sizeof
+												  (fail_stack_elt_t)));
+# endif							/* not emacs */
+		}
+
+		regex_grow_registers(num_regs);
+	}
+#endif							/* not MATCH_MAY_ALLOCATE */
+
+	return REG_NOERROR;
+}								/* regex_compile */
+
+/* Subroutines for `regex_compile'.  */
+
+/* Store OP at LOC followed by two-byte integer parameter ARG.  */
+
+static void store_op1(op, loc, arg)
+re_opcode_t op;
+unsigned char *loc;
+int arg;
+{
+	*loc = (unsigned char) op;
+	STORE_NUMBER(loc + 1, arg);
+}
+
+
+/* Like `store_op1', but for two two-byte parameters ARG1 and ARG2.  */
+
+static void store_op2(op, loc, arg1, arg2)
+re_opcode_t op;
+unsigned char *loc;
+int arg1, arg2;
+{
+	*loc = (unsigned char) op;
+	STORE_NUMBER(loc + 1, arg1);
+	STORE_NUMBER(loc + 3, arg2);
+}
+
+
+/* Copy the bytes from LOC to END to open up three bytes of space at LOC
+   for OP followed by two-byte integer parameter ARG.  */
+
+static void insert_op1(op, loc, arg, end)
+re_opcode_t op;
+unsigned char *loc;
+int arg;
+unsigned char *end;
+{
+	register unsigned char *pfrom = end;
+	register unsigned char *pto = end + 3;
+
+	while (pfrom != loc)
+		*--pto = *--pfrom;
+
+	store_op1(op, loc, arg);
+}
+
+
+/* Like `insert_op1', but for two two-byte parameters ARG1 and ARG2.  */
+
+static void insert_op2(op, loc, arg1, arg2, end)
+re_opcode_t op;
+unsigned char *loc;
+int arg1, arg2;
+unsigned char *end;
+{
+	register unsigned char *pfrom = end;
+	register unsigned char *pto = end + 5;
+
+	while (pfrom != loc)
+		*--pto = *--pfrom;
+
+	store_op2(op, loc, arg1, arg2);
+}
+
+
+/* P points to just after a ^ in PATTERN.  Return true if that ^ comes
+   after an alternative or a begin-subexpression.  We assume there is at
+   least one character before the ^.  */
+
+static boolean at_begline_loc_p(pattern, p, syntax)
+const char *pattern, *p;
+reg_syntax_t syntax;
+{
+	const char *prev = p - 2;
+	boolean prev_prev_backslash = prev > pattern && prev[-1] == '\\';
+
+	return
+		/* After a subexpression?  */
+		(*prev == '(' && (syntax & RE_NO_BK_PARENS || prev_prev_backslash))
+		/* After an alternative?  */
+		|| (*prev == '|'
+			&& (syntax & RE_NO_BK_VBAR || prev_prev_backslash));
+}
+
+
+/* The dual of at_begline_loc_p.  This one is for $.  We assume there is
+   at least one character after the $, i.e., `P < PEND'.  */
+
+static boolean at_endline_loc_p(p, pend, syntax)
+const char *p, *pend;
+reg_syntax_t syntax;
+{
+	const char *next = p;
+	boolean next_backslash = *next == '\\';
+	const char *next_next = p + 1 < pend ? p + 1 : 0;
+
+	return
+		/* Before a subexpression?  */
+		(syntax & RE_NO_BK_PARENS ? *next == ')'
+		 : next_backslash && next_next && *next_next == ')')
+		/* Before an alternative?  */
+		|| (syntax & RE_NO_BK_VBAR ? *next == '|'
+			: next_backslash && next_next && *next_next == '|');
+}
+
+
+/* Returns true if REGNUM is in one of COMPILE_STACK's elements and
+   false if it's not.  */
+
+static boolean group_in_compile_stack(compile_stack, regnum)
+compile_stack_type compile_stack;
+regnum_t regnum;
+{
+	int this_element;
+
+	for (this_element = compile_stack.avail - 1;
+		 this_element >= 0; this_element--)
+		if (compile_stack.stack[this_element].regnum == regnum)
+			return true;
+
+	return false;
+}
+
+
+/* Read the ending character of a range (in a bracket expression) from the
+   uncompiled pattern *P_PTR (which ends at PEND).  We assume the
+   starting character is in `P[-2]'.  (`P[-1]' is the character `-'.)
+   Then we set the translation of all bits between the starting and
+   ending characters (inclusive) in the compiled pattern B.
+
+   Return an error code.
+
+   We use these short variable names so we can use the same macros as
+   `regex_compile' itself.  */
+
+static reg_errcode_t compile_range(p_ptr, pend, translate, syntax, b)
+const char **p_ptr, *pend;
+RE_TRANSLATE_TYPE translate;
+reg_syntax_t syntax;
+unsigned char *b;
+{
+	unsigned this_char;
+
+	const char *p = *p_ptr;
+	reg_errcode_t ret;
+	char range_start[2];
+	char range_end[2];
+	char ch[2];
+
+	if (p == pend)
+		return REG_ERANGE;
+
+	/* Fetch the endpoints without translating them; the
+	   appropriate translation is done in the bit-setting loop below.  */
+	range_start[0] = p[-2];
+	range_start[1] = '\0';
+	range_end[0] = p[0];
+	range_end[1] = '\0';
+
+	/* Have to increment the pointer into the pattern string, so the
+	   caller isn't still at the ending character.  */
+	(*p_ptr)++;
+
+	/* Report an error if the range is empty and the syntax prohibits this.  */
+	ret = syntax & RE_NO_EMPTY_RANGES ? REG_ERANGE : REG_NOERROR;
+
+	/* Here we see why `this_char' has to be larger than an `unsigned
+	   char' -- we would otherwise go into an infinite loop, since all
+	   characters <= 0xff.  */
+	ch[1] = '\0';
+	for (this_char = 0; this_char <= (unsigned char) -1; ++this_char) {
+		ch[0] = this_char;
+		if (strcoll(range_start, ch) <= 0 && strcoll(ch, range_end) <= 0) {
+			SET_LIST_BIT(TRANSLATE(this_char));
+			ret = REG_NOERROR;
+		}
+	}
+
+	return ret;
+}
+
+/* re_compile_fastmap computes a ``fastmap'' for the compiled pattern in
+   BUFP.  A fastmap records which of the (1 << BYTEWIDTH) possible
+   characters can start a string that matches the pattern.  This fastmap
+   is used by re_search to skip quickly over impossible starting points.
+
+   The caller must supply the address of a (1 << BYTEWIDTH)-byte data
+   area as BUFP->fastmap.
+
+   We set the `fastmap', `fastmap_accurate', and `can_be_null' fields in
+   the pattern buffer.
+
+   Returns 0 if we succeed, -2 if an internal error.   */
+
+int re_compile_fastmap(bufp)
+struct re_pattern_buffer *bufp;
+{
+	int j, k;
+
+#ifdef MATCH_MAY_ALLOCATE
+	fail_stack_type fail_stack;
+#endif
+#ifndef REGEX_MALLOC
+	char *destination;
+#endif
+
+	register char *fastmap = bufp->fastmap;
+	unsigned char *pattern = bufp->buffer;
+	unsigned char *p = pattern;
+	register unsigned char *pend = pattern + bufp->used;
+
+#ifdef REL_ALLOC
+	/* This holds the pointer to the failure stack, when
+	   it is allocated relocatably.  */
+	fail_stack_elt_t *failure_stack_ptr;
+#endif
+
+	/* Assume that each path through the pattern can be null until
+	   proven otherwise.  We set this false at the bottom of switch
+	   statement, to which we get only if a particular path doesn't
+	   match the empty string.  */
+	boolean path_can_be_null = true;
+
+	/* We aren't doing a `succeed_n' to begin with.  */
+	boolean succeed_n_p = false;
+
+	assert(fastmap != NULL && p != NULL);
+
+	INIT_FAIL_STACK();
+	bzero(fastmap, 1 << BYTEWIDTH);	/* Assume nothing's valid.  */
+	bufp->fastmap_accurate = 1;	/* It will be when we're done.  */
+	bufp->can_be_null = 0;
+
+	while (1) {
+		if (p == pend || *p == succeed) {
+			/* We have reached the (effective) end of pattern.  */
+			if (!FAIL_STACK_EMPTY()) {
+				bufp->can_be_null |= path_can_be_null;
+
+				/* Reset for next path.  */
+				path_can_be_null = true;
+
+				p = fail_stack.stack[--fail_stack.avail].pointer;
+
+				continue;
+			} else
+				break;
+		}
+
+		/* We should never be about to go beyond the end of the pattern.  */
+		assert(p < pend);
+
+		switch (SWITCH_ENUM_CAST((re_opcode_t) * p++)) {
+
+			/* I guess the idea here is to simply not bother with a fastmap
+			   if a backreference is used, since it's too hard to figure out
+			   the fastmap for the corresponding group.  Setting
+			   `can_be_null' stops `re_search_2' from using the fastmap, so
+			   that is all we do.  */
+		case duplicate:
+			bufp->can_be_null = 1;
+			goto done;
+
+
+			/* Following are the cases which match a character.  These end
+			   with `break'.  */
+
+		case exactn:
+			fastmap[p[1]] = 1;
+			break;
+
+
+		case charset:
+			for (j = *p++ * BYTEWIDTH - 1; j >= 0; j--)
+				if (p[j / BYTEWIDTH] & (1 << (j % BYTEWIDTH)))
+					fastmap[j] = 1;
+			break;
+
+
+		case charset_not:
+			/* Chars beyond end of map must be allowed.  */
+			for (j = *p * BYTEWIDTH; j < (1 << BYTEWIDTH); j++)
+				fastmap[j] = 1;
+
+			for (j = *p++ * BYTEWIDTH - 1; j >= 0; j--)
+				if (!(p[j / BYTEWIDTH] & (1 << (j % BYTEWIDTH))))
+					fastmap[j] = 1;
+			break;
+
+
+		case wordchar:
+			for (j = 0; j < (1 << BYTEWIDTH); j++)
+				if (SYNTAX(j) == Sword)
+					fastmap[j] = 1;
+			break;
+
+
+		case notwordchar:
+			for (j = 0; j < (1 << BYTEWIDTH); j++)
+				if (SYNTAX(j) != Sword)
+					fastmap[j] = 1;
+			break;
+
+
+		case anychar:
+		{
+			int fastmap_newline = fastmap['\n'];
+
+			/* `.' matches anything ...  */
+			for (j = 0; j < (1 << BYTEWIDTH); j++)
+				fastmap[j] = 1;
+
+			/* ... except perhaps newline.  */
+			if (!(bufp->syntax & RE_DOT_NEWLINE))
+				fastmap['\n'] = fastmap_newline;
+
+			/* Return if we have already set `can_be_null'; if we have,
+			   then the fastmap is irrelevant.  Something's wrong here.  */
+			else if (bufp->can_be_null)
+				goto done;
+
+			/* Otherwise, have to check alternative paths.  */
+			break;
+		}
+
+#ifdef emacs
+		case syntaxspec:
+			k = *p++;
+			for (j = 0; j < (1 << BYTEWIDTH); j++)
+				if (SYNTAX(j) == (enum syntaxcode) k)
+					fastmap[j] = 1;
+			break;
+
+
+		case notsyntaxspec:
+			k = *p++;
+			for (j = 0; j < (1 << BYTEWIDTH); j++)
+				if (SYNTAX(j) != (enum syntaxcode) k)
+					fastmap[j] = 1;
+			break;
+
+
+			/* All cases after this match the empty string.  These end with
+			   `continue'.  */
+
+
+		case before_dot:
+		case at_dot:
+		case after_dot:
+			continue;
+#endif							/* emacs */
+
+
+		case no_op:
+		case begline:
+		case endline:
+		case begbuf:
+		case endbuf:
+		case wordbound:
+		case notwordbound:
+		case wordbeg:
+		case wordend:
+		case push_dummy_failure:
+			continue;
+
+
+		case jump_n:
+		case pop_failure_jump:
+		case maybe_pop_jump:
+		case jump:
+		case jump_past_alt:
+		case dummy_failure_jump:
+			EXTRACT_NUMBER_AND_INCR(j, p);
+			p += j;
+			if (j > 0)
+				continue;
+
+			/* Jump backward implies we just went through the body of a
+			   loop and matched nothing.  Opcode jumped to should be
+			   `on_failure_jump' or `succeed_n'.  Just treat it like an
+			   ordinary jump.  For a * loop, it has pushed its failure
+			   point already; if so, discard that as redundant.  */
+			if ((re_opcode_t) * p != on_failure_jump
+				&& (re_opcode_t) * p != succeed_n)
+				continue;
+
+			p++;
+			EXTRACT_NUMBER_AND_INCR(j, p);
+			p += j;
+
+			/* If what's on the stack is where we are now, pop it.  */
+			if (!FAIL_STACK_EMPTY()
+				&& fail_stack.stack[fail_stack.avail - 1].pointer == p)
+				fail_stack.avail--;
+
+			continue;
+
+
+		case on_failure_jump:
+		case on_failure_keep_string_jump:
+		  handle_on_failure_jump:
+			EXTRACT_NUMBER_AND_INCR(j, p);
+
+			/* For some patterns, e.g., `(a?)?', `p+j' here points to the
+			   end of the pattern.  We don't want to push such a point,
+			   since when we restore it above, entering the switch will
+			   increment `p' past the end of the pattern.  We don't need
+			   to push such a point since we obviously won't find any more
+			   fastmap entries beyond `pend'.  Such a pattern can match
+			   the null string, though.  */
+			if (p + j < pend) {
+				if (!PUSH_PATTERN_OP(p + j, fail_stack)) {
+					RESET_FAIL_STACK();
+					return -2;
+				}
+			} else
+				bufp->can_be_null = 1;
+
+			if (succeed_n_p) {
+				EXTRACT_NUMBER_AND_INCR(k, p);	/* Skip the n.  */
+				succeed_n_p = false;
+			}
+
+			continue;
+
+
+		case succeed_n:
+			/* Get to the number of times to succeed.  */
+			p += 2;
+
+			/* Increment p past the n for when k != 0.  */
+			EXTRACT_NUMBER_AND_INCR(k, p);
+			if (k == 0) {
+				p -= 4;
+				succeed_n_p = true;	/* Spaghetti code alert.  */
+				goto handle_on_failure_jump;
+			}
+			continue;
+
+
+		case set_number_at:
+			p += 4;
+			continue;
+
+
+		case start_memory:
+		case stop_memory:
+			p += 2;
+			continue;
+
+
+		default:
+			abort();			/* We have listed all the cases.  */
+		}						/* switch *p++ */
+
+		/* Getting here means we have found the possible starting
+		   characters for one path of the pattern -- and that the empty
+		   string does not match.  We need not follow this path further.
+		   Instead, look at the next alternative (remembered on the
+		   stack), or quit if no more.  The test at the top of the loop
+		   does these things.  */
+		path_can_be_null = false;
+		p = pend;
+	}							/* while p */
+
+	/* Set `can_be_null' for the last path (also the first path, if the
+	   pattern is empty).  */
+	bufp->can_be_null |= path_can_be_null;
+
+  done:
+	RESET_FAIL_STACK();
+	return 0;
+}								/* re_compile_fastmap */
+
+#ifdef _LIBC
+weak_alias(__re_compile_fastmap, re_compile_fastmap)
+#endif
+/* Set REGS to hold NUM_REGS registers, storing them in STARTS and
+   ENDS.  Subsequent matches using PATTERN_BUFFER and REGS will use
+   this memory for recording register information.  STARTS and ENDS
+   must be allocated using the malloc library routine, and must each
+   be at least NUM_REGS * sizeof (regoff_t) bytes long.
+
+   If NUM_REGS == 0, then subsequent matches should allocate their own
+   register data.
+
+   Unless this function is called, the first search or match using
+   PATTERN_BUFFER will allocate its own register data, without
+   freeing the old data.  */
+void re_set_registers(bufp, regs, num_regs, starts, ends)
+struct re_pattern_buffer *bufp;
+struct re_registers *regs;
+unsigned num_regs;
+regoff_t *starts, *ends;
+{
+	if (num_regs) {
+		bufp->regs_allocated = REGS_REALLOCATE;
+		regs->num_regs = num_regs;
+		regs->start = starts;
+		regs->end = ends;
+	} else {
+		bufp->regs_allocated = REGS_UNALLOCATED;
+		regs->num_regs = 0;
+		regs->start = regs->end = (regoff_t *) 0;
+	}
+}
+
+#ifdef _LIBC
+weak_alias(__re_set_registers, re_set_registers)
+#endif
+/* Searching routines.  */
+/* Like re_search_2, below, but only one string is specified, and
+   doesn't let you say where to stop matching. */
+int re_search(bufp, string, size, startpos, range, regs)
+struct re_pattern_buffer *bufp;
+const char *string;
+int size, startpos, range;
+struct re_registers *regs;
+{
+	return re_search_2(bufp, NULL, 0, string, size, startpos, range,
+					   regs, size);
+}
+
+#ifdef _LIBC
+weak_alias(__re_search, re_search)
+#endif
+/* Using the compiled pattern in BUFP->buffer, first tries to match the
+   virtual concatenation of STRING1 and STRING2, starting first at index
+   STARTPOS, then at STARTPOS + 1, and so on.
+
+   STRING1 and STRING2 have length SIZE1 and SIZE2, respectively.
+
+   RANGE is how far to scan while trying to match.  RANGE = 0 means try
+   only at STARTPOS; in general, the last start tried is STARTPOS +
+   RANGE.
+
+   In REGS, return the indices of the virtual concatenation of STRING1
+   and STRING2 that matched the entire BUFP->buffer and its contained
+   subexpressions.
+
+   Do not consider matching one past the index STOP in the virtual
+   concatenation of STRING1 and STRING2.
+
+   We return either the position in the strings at which the match was
+   found, -1 if no match, or -2 if error (such as failure
+   stack overflow).  */
+int
+re_search_2(bufp, string1, size1, string2, size2, startpos, range, regs,
+			stop)
+struct re_pattern_buffer *bufp;
+const char *string1, *string2;
+int size1, size2;
+int startpos;
+int range;
+struct re_registers *regs;
+int stop;
+{
+	int val;
+	register char *fastmap = bufp->fastmap;
+	register RE_TRANSLATE_TYPE translate = bufp->translate;
+	int total_size = size1 + size2;
+	int endpos = startpos + range;
+
+	/* Check for out-of-range STARTPOS.  */
+	if (startpos < 0 || startpos > total_size)
+		return -1;
+
+	/* Fix up RANGE if it might eventually take us outside
+	   the virtual concatenation of STRING1 and STRING2.
+	   Make sure we won't move STARTPOS below 0 or above TOTAL_SIZE.  */
+	if (endpos < 0)
+		range = 0 - startpos;
+	else if (endpos > total_size)
+		range = total_size - startpos;
+
+	/* If the search isn't to be a backwards one, don't waste time in a
+	   search for a pattern that must be anchored.  */
+	if (bufp->used > 0 && range > 0
+		&& ((re_opcode_t) bufp->buffer[0] == begbuf
+			/* `begline' is like `begbuf' if it cannot match at newlines.  */
+			|| ((re_opcode_t) bufp->buffer[0] == begline
+				&& !bufp->newline_anchor))) {
+		if (startpos > 0)
+			return -1;
+		else
+			range = 1;
+	}
+#ifdef emacs
+	/* In a forward search for something that starts with \=.
+	   don't keep searching past point.  */
+	if (bufp->used > 0 && (re_opcode_t) bufp->buffer[0] == at_dot
+		&& range > 0) {
+		range = PT - startpos;
+		if (range <= 0)
+			return -1;
+	}
+#endif							/* emacs */
+
+	/* Update the fastmap now if not correct already.  */
+	if (fastmap && !bufp->fastmap_accurate)
+		if (re_compile_fastmap(bufp) == -2)
+			return -2;
+
+	/* Loop through the string, looking for a place to start matching.  */
+	for (;;) {
+		/* If a fastmap is supplied, skip quickly over characters that
+		   cannot be the start of a match.  If the pattern can match the
+		   null string, however, we don't need to skip characters; we want
+		   the first null string.  */
+		if (fastmap && startpos < total_size && !bufp->can_be_null) {
+			if (range > 0) {	/* Searching forwards.  */
+				register const char *d;
+				register int lim = 0;
+				int irange = range;
+
+				if (startpos < size1 && startpos + range >= size1)
+					lim = range - (size1 - startpos);
+
+				d =
+					(startpos >=
+					 size1 ? string2 - size1 : string1) + startpos;
+
+				/* Written out as an if-else to avoid testing `translate'
+				   inside the loop.  */
+				if (translate)
+					while (range > lim && !fastmap[(unsigned char)
+												   translate[
+															 (unsigned
+															  char) *d++]])
+						range--;
+				else
+					while (range > lim && !fastmap[(unsigned char) *d++])
+						range--;
+
+				startpos += irange - range;
+			} else {			/* Searching backwards.  */
+
+				register char c = (size1 == 0 || startpos >= size1
+								   ? string2[startpos - size1]
+								   : string1[startpos]);
+
+				if (!fastmap[(unsigned char) TRANSLATE(c)])
+					goto advance;
+			}
+		}
+
+		/* If can't match the null string, and that's all we have left, fail.  */
+		if (range >= 0 && startpos == total_size && fastmap
+			&& !bufp->can_be_null) return -1;
+
+		val = re_match_2_internal(bufp, string1, size1, string2, size2,
+								  startpos, regs, stop);
+#ifndef REGEX_MALLOC
+# ifdef C_ALLOCA
+		alloca(0);
+# endif
+#endif
+
+		if (val >= 0)
+			return startpos;
+
+		if (val == -2)
+			return -2;
+
+	  advance:
+		if (!range)
+			break;
+		else if (range > 0) {
+			range--;
+			startpos++;
+		} else {
+			range++;
+			startpos--;
+		}
+	}
+	return -1;
+}								/* re_search_2 */
+
+#ifdef _LIBC
+weak_alias(__re_search_2, re_search_2)
+#endif
+/* This converts PTR, a pointer into one of the search strings `string1'
+   and `string2' into an offset from the beginning of that string.  */
+#define POINTER_TO_OFFSET(ptr)			\
+  (FIRST_STRING_P (ptr)				\
+   ? ((regoff_t) ((ptr) - string1))		\
+   : ((regoff_t) ((ptr) - string2 + size1)))
+/* Macros for dealing with the split strings in re_match_2.  */
+#define MATCHING_IN_FIRST_STRING  (dend == end_match_1)
+/* Call before fetching a character with *d.  This switches over to
+   string2 if necessary.  */
+#define PREFETCH()							\
+  while (d == dend)						    	\
+    {									\
+      /* End of string2 => fail.  */					\
+      if (dend == end_match_2) 						\
+        goto fail;							\
+      /* End of string1 => advance to string2.  */ 			\
+      d = string2;						        \
+      dend = end_match_2;						\
+    }
+/* Test if at very beginning or at very end of the virtual concatenation
+   of `string1' and `string2'.  If only one string, it's `string2'.  */
+#define AT_STRINGS_BEG(d) ((d) == (size1 ? string1 : string2) || !size2)
+#define AT_STRINGS_END(d) ((d) == end2)
+/* Test if D points to a character which is word-constituent.  We have
+   two special cases to check for: if past the end of string1, look at
+   the first character in string2; and if before the beginning of
+   string2, look at the last character in string1.  */
+#define WORDCHAR_P(d)							\
+  (SYNTAX ((d) == end1 ? *string2					\
+           : (d) == string2 - 1 ? *(end1 - 1) : *(d))			\
+   == Sword)
+/* Disabled due to a compiler bug -- see comment at case wordbound */
+#if 0
+/* Test if the character before D and the one at D differ with respect
+   to being word-constituent.  */
+#define AT_WORD_BOUNDARY(d)						\
+  (AT_STRINGS_BEG (d) || AT_STRINGS_END (d)				\
+   || WORDCHAR_P (d - 1) != WORDCHAR_P (d))
+#endif
+/* Free everything we malloc.  */
+#ifdef MATCH_MAY_ALLOCATE
+# define FREE_VAR(var) if (var) REGEX_FREE (var); var = NULL
+# define FREE_VARIABLES()						\
+  do {									\
+    REGEX_FREE_STACK (fail_stack.stack);				\
+    FREE_VAR (regstart);						\
+    FREE_VAR (regend);							\
+    FREE_VAR (old_regstart);						\
+    FREE_VAR (old_regend);						\
+    FREE_VAR (best_regstart);						\
+    FREE_VAR (best_regend);						\
+    FREE_VAR (reg_info);						\
+    FREE_VAR (reg_dummy);						\
+    FREE_VAR (reg_info_dummy);						\
+  } while (0)
+#else
+# define FREE_VARIABLES() ((void)0)	/* Do nothing!  But inhibit gcc warning. */
+#endif							/* not MATCH_MAY_ALLOCATE */
+/* These values must meet several constraints.  They must not be valid
+   register values; since we have a limit of 255 registers (because
+   we use only one byte in the pattern for the register number), we can
+   use numbers larger than 255.  They must differ by 1, because of
+   NUM_FAILURE_ITEMS above.  And the value for the lowest register must
+   be larger than the value for the highest register, so we do not try
+   to actually save any registers when none are active.  */
+#define NO_HIGHEST_ACTIVE_REG (1 << BYTEWIDTH)
+#define NO_LOWEST_ACTIVE_REG (NO_HIGHEST_ACTIVE_REG + 1)
+/* Matching routines.  */
+#ifndef emacs					/* Emacs never uses this.  */
+/* re_match is like re_match_2 except it takes only a single string.  */
+int re_match(bufp, string, size, pos, regs)
+struct re_pattern_buffer *bufp;
+const char *string;
+int size, pos;
+struct re_registers *regs;
+{
+	int result = re_match_2_internal(bufp, NULL, 0, string, size,
+									 pos, regs, size);
+
+# ifndef REGEX_MALLOC
+#  ifdef C_ALLOCA
+	alloca(0);
+#  endif
+# endif
+	return result;
+}
+
+# ifdef _LIBC
+weak_alias(__re_match, re_match)
+# endif
+#endif							/* not emacs */
+static boolean group_match_null_string_p _RE_ARGS((unsigned char **p,
+												   unsigned char *end,
+												   register_info_type *
+
+												   reg_info));
+static boolean alt_match_null_string_p
+_RE_ARGS(
+
+		 (unsigned char *p, unsigned char *end,
+		  register_info_type * reg_info));
+static boolean common_op_match_null_string_p
+_RE_ARGS(
+
+		 (unsigned char **p, unsigned char *end,
+		  register_info_type * reg_info));
+static int bcmp_translate
+_RE_ARGS((const char *s1, const char *s2, int len, char *translate));
+
+/* re_match_2 matches the compiled pattern in BUFP against the
+   the (virtual) concatenation of STRING1 and STRING2 (of length SIZE1
+   and SIZE2, respectively).  We start matching at POS, and stop
+   matching at STOP.
+
+   If REGS is non-null and the `no_sub' field of BUFP is nonzero, we
+   store offsets for the substring each group matched in REGS.  See the
+   documentation for exactly how many groups we fill.
+
+   We return -1 if no match, -2 if an internal error (such as the
+   failure stack overflowing).  Otherwise, we return the length of the
+   matched substring.  */
+
+int re_match_2(bufp, string1, size1, string2, size2, pos, regs, stop)
+struct re_pattern_buffer *bufp;
+const char *string1, *string2;
+int size1, size2;
+int pos;
+struct re_registers *regs;
+int stop;
+{
+	int result = re_match_2_internal(bufp, string1, size1, string2, size2,
+									 pos, regs, stop);
+
+#ifndef REGEX_MALLOC
+# ifdef C_ALLOCA
+	alloca(0);
+# endif
+#endif
+	return result;
+}
+
+#ifdef _LIBC
+weak_alias(__re_match_2, re_match_2)
+#endif
+/* This is a separate function so that we can force an alloca cleanup
+   afterwards.  */
+static int
+re_match_2_internal(bufp, string1, size1, string2, size2, pos, regs, stop)
+struct re_pattern_buffer *bufp;
+const char *string1, *string2;
+int size1, size2;
+int pos;
+struct re_registers *regs;
+int stop;
+{
+	/* General temporaries.  */
+	int mcnt;
+	unsigned char *p1;
+
+	/* Just past the end of the corresponding string.  */
+	const char *end1, *end2;
+
+	/* Pointers into string1 and string2, just past the last characters in
+	   each to consider matching.  */
+	const char *end_match_1, *end_match_2;
+
+	/* Where we are in the data, and the end of the current string.  */
+	const char *d, *dend;
+
+	/* Where we are in the pattern, and the end of the pattern.  */
+	unsigned char *p = bufp->buffer;
+	register unsigned char *pend = p + bufp->used;
+
+	/* Mark the opcode just after a start_memory, so we can test for an
+	   empty subpattern when we get to the stop_memory.  */
+	unsigned char *just_past_start_mem = 0;
+
+	/* We use this to map every character in the string.  */
+	RE_TRANSLATE_TYPE translate = bufp->translate;
+
+	/* Failure point stack.  Each place that can handle a failure further
+	   down the line pushes a failure point on this stack.  It consists of
+	   restart, regend, and reg_info for all registers corresponding to
+	   the subexpressions we're currently inside, plus the number of such
+	   registers, and, finally, two char *'s.  The first char * is where
+	   to resume scanning the pattern; the second one is where to resume
+	   scanning the strings.  If the latter is zero, the failure point is
+	   a ``dummy''; if a failure happens and the failure point is a dummy,
+	   it gets discarded and the next next one is tried.  */
+#ifdef MATCH_MAY_ALLOCATE		/* otherwise, this is global.  */
+	fail_stack_type fail_stack;
+#endif
+#ifdef DEBUG
+	static unsigned failure_id;
+	unsigned nfailure_points_pushed = 0, nfailure_points_popped = 0;
+#endif
+
+#ifdef REL_ALLOC
+	/* This holds the pointer to the failure stack, when
+	   it is allocated relocatably.  */
+	fail_stack_elt_t *failure_stack_ptr;
+#endif
+
+	/* We fill all the registers internally, independent of what we
+	   return, for use in backreferences.  The number here includes
+	   an element for register zero.  */
+	size_t num_regs = bufp->re_nsub + 1;
+
+	/* The currently active registers.  */
+	active_reg_t lowest_active_reg = NO_LOWEST_ACTIVE_REG;
+	active_reg_t highest_active_reg = NO_HIGHEST_ACTIVE_REG;
+
+	/* Information on the contents of registers. These are pointers into
+	   the input strings; they record just what was matched (on this
+	   attempt) by a subexpression part of the pattern, that is, the
+	   regnum-th regstart pointer points to where in the pattern we began
+	   matching and the regnum-th regend points to right after where we
+	   stopped matching the regnum-th subexpression.  (The zeroth register
+	   keeps track of what the whole pattern matches.)  */
+#ifdef MATCH_MAY_ALLOCATE		/* otherwise, these are global.  */
+	const char **regstart, **regend;
+#endif
+
+	/* If a group that's operated upon by a repetition operator fails to
+	   match anything, then the register for its start will need to be
+	   restored because it will have been set to wherever in the string we
+	   are when we last see its open-group operator.  Similarly for a
+	   register's end.  */
+#ifdef MATCH_MAY_ALLOCATE		/* otherwise, these are global.  */
+	const char **old_regstart, **old_regend;
+#endif
+
+	/* The is_active field of reg_info helps us keep track of which (possibly
+	   nested) subexpressions we are currently in. The matched_something
+	   field of reg_info[reg_num] helps us tell whether or not we have
+	   matched any of the pattern so far this time through the reg_num-th
+	   subexpression.  These two fields get reset each time through any
+	   loop their register is in.  */
+#ifdef MATCH_MAY_ALLOCATE		/* otherwise, this is global.  */
+	register_info_type *reg_info;
+#endif
+
+	/* The following record the register info as found in the above
+	   variables when we find a match better than any we've seen before.
+	   This happens as we backtrack through the failure points, which in
+	   turn happens only if we have not yet matched the entire string. */
+	unsigned best_regs_set = false;
+
+#ifdef MATCH_MAY_ALLOCATE		/* otherwise, these are global.  */
+	const char **best_regstart, **best_regend;
+#endif
+
+	/* Logically, this is `best_regend[0]'.  But we don't want to have to
+	   allocate space for that if we're not allocating space for anything
+	   else (see below).  Also, we never need info about register 0 for
+	   any of the other register vectors, and it seems rather a kludge to
+	   treat `best_regend' differently than the rest.  So we keep track of
+	   the end of the best match so far in a separate variable.  We
+	   initialize this to NULL so that when we backtrack the first time
+	   and need to test it, it's not garbage.  */
+	const char *match_end = NULL;
+
+	/* This helps SET_REGS_MATCHED avoid doing redundant work.  */
+	int set_regs_matched_done = 0;
+
+	/* Used when we pop values we don't care about.  */
+#ifdef MATCH_MAY_ALLOCATE		/* otherwise, these are global.  */
+	const char **reg_dummy;
+	register_info_type *reg_info_dummy;
+#endif
+
+#ifdef DEBUG
+	/* Counts the total number of registers pushed.  */
+	unsigned num_regs_pushed = 0;
+#endif
+
+	DEBUG_PRINT1("\n\nEntering re_match_2.\n");
+
+	INIT_FAIL_STACK();
+
+#ifdef MATCH_MAY_ALLOCATE
+	/* Do not bother to initialize all the register variables if there are
+	   no groups in the pattern, as it takes a fair amount of time.  If
+	   there are groups, we include space for register 0 (the whole
+	   pattern), even though we never use it, since it simplifies the
+	   array indexing.  We should fix this.  */
+	if (bufp->re_nsub) {
+		regstart = REGEX_TALLOC(num_regs, const char *);
+		regend = REGEX_TALLOC(num_regs, const char *);
+		old_regstart = REGEX_TALLOC(num_regs, const char *);
+		old_regend = REGEX_TALLOC(num_regs, const char *);
+		best_regstart = REGEX_TALLOC(num_regs, const char *);
+		best_regend = REGEX_TALLOC(num_regs, const char *);
+
+		reg_info = REGEX_TALLOC(num_regs, register_info_type);
+		reg_dummy = REGEX_TALLOC(num_regs, const char *);
+
+		reg_info_dummy = REGEX_TALLOC(num_regs, register_info_type);
+
+		if (!(regstart && regend && old_regstart && old_regend && reg_info
+			  && best_regstart && best_regend && reg_dummy
+			  && reg_info_dummy)) {
+			FREE_VARIABLES();
+			return -2;
+		}
+	} else {
+		/* We must initialize all our variables to NULL, so that
+		   `FREE_VARIABLES' doesn't try to free them.  */
+		regstart = regend = old_regstart = old_regend = best_regstart
+			= best_regend = reg_dummy = NULL;
+		reg_info = reg_info_dummy = (register_info_type *) NULL;
+	}
+#endif							/* MATCH_MAY_ALLOCATE */
+
+	/* The starting position is bogus.  */
+	if (pos < 0 || pos > size1 + size2) {
+		FREE_VARIABLES();
+		return -1;
+	}
+
+	/* Initialize subexpression text positions to -1 to mark ones that no
+	   start_memory/stop_memory has been seen for. Also initialize the
+	   register information struct.  */
+	for (mcnt = 1; (unsigned) mcnt < num_regs; mcnt++) {
+		regstart[mcnt] = regend[mcnt]
+			= old_regstart[mcnt] = old_regend[mcnt] = REG_UNSET_VALUE;
+
+		REG_MATCH_NULL_STRING_P(reg_info[mcnt]) = MATCH_NULL_UNSET_VALUE;
+		IS_ACTIVE(reg_info[mcnt]) = 0;
+		MATCHED_SOMETHING(reg_info[mcnt]) = 0;
+		EVER_MATCHED_SOMETHING(reg_info[mcnt]) = 0;
+	}
+
+	/* We move `string1' into `string2' if the latter's empty -- but not if
+	   `string1' is null.  */
+	if (size2 == 0 && string1 != NULL) {
+		string2 = string1;
+		size2 = size1;
+		string1 = 0;
+		size1 = 0;
+	}
+	end1 = string1 + size1;
+	end2 = string2 + size2;
+
+	/* Compute where to stop matching, within the two strings.  */
+	if (stop <= size1) {
+		end_match_1 = string1 + stop;
+		end_match_2 = string2;
+	} else {
+		end_match_1 = end1;
+		end_match_2 = string2 + stop - size1;
+	}
+
+	/* `p' scans through the pattern as `d' scans through the data.
+	   `dend' is the end of the input string that `d' points within.  `d'
+	   is advanced into the following input string whenever necessary, but
+	   this happens before fetching; therefore, at the beginning of the
+	   loop, `d' can be pointing at the end of a string, but it cannot
+	   equal `string2'.  */
+	if (size1 > 0 && pos <= size1) {
+		d = string1 + pos;
+		dend = end_match_1;
+	} else {
+		d = string2 + pos - size1;
+		dend = end_match_2;
+	}
+
+	DEBUG_PRINT1("The compiled pattern is:\n");
+	DEBUG_PRINT_COMPILED_PATTERN(bufp, p, pend);
+	DEBUG_PRINT1("The string to match is: `");
+	DEBUG_PRINT_DOUBLE_STRING(d, string1, size1, string2, size2);
+	DEBUG_PRINT1("'\n");
+
+	/* This loops over pattern commands.  It exits by returning from the
+	   function if the match is complete, or it drops through if the match
+	   fails at this starting point in the input data.  */
+	for (;;) {
+#ifdef _LIBC
+		DEBUG_PRINT2("\n%p: ", p);
+#else
+		DEBUG_PRINT2("\n0x%x: ", p);
+#endif
+
+		if (p == pend) {		/* End of pattern means we might have succeeded.  */
+			DEBUG_PRINT1("end of pattern ... ");
+
+			/* If we haven't matched the entire string, and we want the
+			   longest match, try backtracking.  */
+			if (d != end_match_2) {
+				/* 1 if this match ends in the same string (string1 or string2)
+				   as the best previous match.  */
+				boolean same_str_p = (FIRST_STRING_P(match_end)
+									  == MATCHING_IN_FIRST_STRING);
+
+				/* 1 if this match is the best seen so far.  */
+				boolean best_match_p;
+
+				/* AIX compiler got confused when this was combined
+				   with the previous declaration.  */
+				if (same_str_p)
+					best_match_p = d > match_end;
+				else
+					best_match_p = !MATCHING_IN_FIRST_STRING;
+
+				DEBUG_PRINT1("backtracking.\n");
+
+				if (!FAIL_STACK_EMPTY()) {	/* More failure points to try.  */
+
+					/* If exceeds best match so far, save it.  */
+					if (!best_regs_set || best_match_p) {
+						best_regs_set = true;
+						match_end = d;
+
+						DEBUG_PRINT1("\nSAVING match as best so far.\n");
+
+						for (mcnt = 1; (unsigned) mcnt < num_regs; mcnt++) {
+							best_regstart[mcnt] = regstart[mcnt];
+							best_regend[mcnt] = regend[mcnt];
+						}
+					}
+					goto fail;
+				}
+
+				/* If no failure points, don't restore garbage.  And if
+				   last match is real best match, don't restore second
+				   best one. */
+				else if (best_regs_set && !best_match_p) {
+				  restore_best_regs:
+					/* Restore best match.  It may happen that `dend ==
+					   end_match_1' while the restored d is in string2.
+					   For example, the pattern `x.*y.*z' against the
+					   strings `x-' and `y-z-', if the two strings are
+					   not consecutive in memory.  */
+					DEBUG_PRINT1("Restoring best registers.\n");
+
+					d = match_end;
+					dend = ((d >= string1 && d <= end1)
+							? end_match_1 : end_match_2);
+
+					for (mcnt = 1; (unsigned) mcnt < num_regs; mcnt++) {
+						regstart[mcnt] = best_regstart[mcnt];
+						regend[mcnt] = best_regend[mcnt];
+					}
+				}
+			}
+			/* d != end_match_2 */
+		  succeed_label:
+			DEBUG_PRINT1("Accepting match.\n");
+
+			/* If caller wants register contents data back, do it.  */
+			if (regs && !bufp->no_sub) {
+				/* Have the register data arrays been allocated?  */
+				if (bufp->regs_allocated == REGS_UNALLOCATED) {	/* No.  So allocate them with malloc.  We need one
+																   extra element beyond `num_regs' for the `-1' marker
+																   GNU code uses.  */
+					regs->num_regs = MAX(RE_NREGS, num_regs + 1);
+					regs->start = TALLOC(regs->num_regs, regoff_t);
+					regs->end = TALLOC(regs->num_regs, regoff_t);
+					if (regs->start == NULL || regs->end == NULL) {
+						FREE_VARIABLES();
+						return -2;
+					}
+					bufp->regs_allocated = REGS_REALLOCATE;
+				} else if (bufp->regs_allocated == REGS_REALLOCATE) {	/* Yes.  If we need more elements than were already
+																		   allocated, reallocate them.  If we need fewer, just
+																		   leave it alone.  */
+					if (regs->num_regs < num_regs + 1) {
+						regs->num_regs = num_regs + 1;
+						RETALLOC(regs->start, regs->num_regs, regoff_t);
+						RETALLOC(regs->end, regs->num_regs, regoff_t);
+						if (regs->start == NULL || regs->end == NULL) {
+							FREE_VARIABLES();
+							return -2;
+						}
+					}
+				} else {
+					/* These braces fend off a "empty body in an else-statement"
+					   warning under GCC when assert expands to nothing.  */
+					assert(bufp->regs_allocated == REGS_FIXED);
+				}
+
+				/* Convert the pointer data in `regstart' and `regend' to
+				   indices.  Register zero has to be set differently,
+				   since we haven't kept track of any info for it.  */
+				if (regs->num_regs > 0) {
+					regs->start[0] = pos;
+					regs->end[0] = (MATCHING_IN_FIRST_STRING
+									? ((regoff_t) (d - string1))
+									: ((regoff_t) (d - string2 + size1)));
+				}
+
+				/* Go through the first `min (num_regs, regs->num_regs)'
+				   registers, since that is all we initialized.  */
+				for (mcnt = 1;
+					 (unsigned) mcnt < MIN(num_regs, regs->num_regs);
+					 mcnt++) {
+					if (REG_UNSET(regstart[mcnt])
+						|| REG_UNSET(regend[mcnt])) regs->start[mcnt] =
+							regs->end[mcnt] = -1;
+					else {
+						regs->start[mcnt]
+							= (regoff_t) POINTER_TO_OFFSET(regstart[mcnt]);
+						regs->end[mcnt]
+							= (regoff_t) POINTER_TO_OFFSET(regend[mcnt]);
+					}
+				}
+
+				/* If the regs structure we return has more elements than
+				   were in the pattern, set the extra elements to -1.  If
+				   we (re)allocated the registers, this is the case,
+				   because we always allocate enough to have at least one
+				   -1 at the end.  */
+				for (mcnt = num_regs; (unsigned) mcnt < regs->num_regs;
+					 mcnt++)
+					regs->start[mcnt] = regs->end[mcnt] = -1;
+			}
+			/* regs && !bufp->no_sub */
+			DEBUG_PRINT4
+				("%u failure points pushed, %u popped (%u remain).\n",
+				 nfailure_points_pushed, nfailure_points_popped,
+				 nfailure_points_pushed - nfailure_points_popped);
+			DEBUG_PRINT2("%u registers pushed.\n", num_regs_pushed);
+
+			mcnt = d - pos - (MATCHING_IN_FIRST_STRING
+							  ? string1 : string2 - size1);
+
+			DEBUG_PRINT2("Returning %d from re_match_2.\n", mcnt);
+
+			FREE_VARIABLES();
+			return mcnt;
+		}
+
+		/* Otherwise match next pattern command.  */
+		switch (SWITCH_ENUM_CAST((re_opcode_t) * p++)) {
+			/* Ignore these.  Used to ignore the n of succeed_n's which
+			   currently have n == 0.  */
+		case no_op:
+			DEBUG_PRINT1("EXECUTING no_op.\n");
+			break;
+
+		case succeed:
+			DEBUG_PRINT1("EXECUTING succeed.\n");
+			goto succeed_label;
+
+			/* Match the next n pattern characters exactly.  The following
+			   byte in the pattern defines n, and the n bytes after that
+			   are the characters to match.  */
+		case exactn:
+			mcnt = *p++;
+			DEBUG_PRINT2("EXECUTING exactn %d.\n", mcnt);
+
+			/* This is written out as an if-else so we don't waste time
+			   testing `translate' inside the loop.  */
+			if (translate) {
+				do {
+					PREFETCH();
+					if ((unsigned char) translate[(unsigned char) *d++]
+						!= (unsigned char) *p++)
+						goto fail;
+				}
+				while (--mcnt);
+			} else {
+				do {
+					PREFETCH();
+					if (*d++ != (char) *p++)
+						goto fail;
+				}
+				while (--mcnt);
+			}
+			SET_REGS_MATCHED();
+			break;
+
+
+			/* Match any character except possibly a newline or a null.  */
+		case anychar:
+			DEBUG_PRINT1("EXECUTING anychar.\n");
+
+			PREFETCH();
+
+			if ((!(bufp->syntax & RE_DOT_NEWLINE) && TRANSLATE(*d) == '\n')
+				|| (bufp->syntax & RE_DOT_NOT_NULL
+					&& TRANSLATE(*d) == '\000')) goto fail;
+
+			SET_REGS_MATCHED();
+			DEBUG_PRINT2("  Matched `%d'.\n", *d);
+			d++;
+			break;
+
+
+		case charset:
+		case charset_not:
+		{
+			register unsigned char c;
+			boolean not = (re_opcode_t) * (p - 1) == charset_not;
+
+			DEBUG_PRINT2("EXECUTING charset%s.\n", not ? "_not" : "");
+
+			PREFETCH();
+			c = TRANSLATE(*d);	/* The character to match.  */
+
+			/* Cast to `unsigned' instead of `unsigned char' in case the
+			   bit list is a full 32 bytes long.  */
+			if (c < (unsigned) (*p * BYTEWIDTH)
+				&& p[1 + c / BYTEWIDTH] & (1 << (c % BYTEWIDTH)))
+				not = !not;
+
+			p += 1 + *p;
+
+			if (!not)
+				goto fail;
+
+			SET_REGS_MATCHED();
+			d++;
+			break;
+		}
+
+
+			/* The beginning of a group is represented by start_memory.
+			   The arguments are the register number in the next byte, and the
+			   number of groups inner to this one in the next.  The text
+			   matched within the group is recorded (in the internal
+			   registers data structure) under the register number.  */
+		case start_memory:
+			DEBUG_PRINT3("EXECUTING start_memory %d (%d):\n", *p, p[1]);
+
+			/* Find out if this group can match the empty string.  */
+			p1 = p;				/* To send to group_match_null_string_p.  */
+
+			if (REG_MATCH_NULL_STRING_P(reg_info[*p]) ==
+				MATCH_NULL_UNSET_VALUE)
+					REG_MATCH_NULL_STRING_P(reg_info[*p]) =
+					group_match_null_string_p(&p1, pend, reg_info);
+
+			/* Save the position in the string where we were the last time
+			   we were at this open-group operator in case the group is
+			   operated upon by a repetition operator, e.g., with `(a*)*b'
+			   against `ab'; then we want to ignore where we are now in
+			   the string in case this attempt to match fails.  */
+			old_regstart[*p] = REG_MATCH_NULL_STRING_P(reg_info[*p])
+				? REG_UNSET(regstart[*p]) ? d : regstart[*p]
+				: regstart[*p];
+			DEBUG_PRINT2("  old_regstart: %d\n",
+						 POINTER_TO_OFFSET(old_regstart[*p]));
+
+			regstart[*p] = d;
+			DEBUG_PRINT2("  regstart: %d\n",
+						 POINTER_TO_OFFSET(regstart[*p]));
+
+			IS_ACTIVE(reg_info[*p]) = 1;
+			MATCHED_SOMETHING(reg_info[*p]) = 0;
+
+			/* Clear this whenever we change the register activity status.  */
+			set_regs_matched_done = 0;
+
+			/* This is the new highest active register.  */
+			highest_active_reg = *p;
+
+			/* If nothing was active before, this is the new lowest active
+			   register.  */
+			if (lowest_active_reg == NO_LOWEST_ACTIVE_REG)
+				lowest_active_reg = *p;
+
+			/* Move past the register number and inner group count.  */
+			p += 2;
+			just_past_start_mem = p;
+
+			break;
+
+
+			/* The stop_memory opcode represents the end of a group.  Its
+			   arguments are the same as start_memory's: the register
+			   number, and the number of inner groups.  */
+		case stop_memory:
+			DEBUG_PRINT3("EXECUTING stop_memory %d (%d):\n", *p, p[1]);
+
+			/* We need to save the string position the last time we were at
+			   this close-group operator in case the group is operated
+			   upon by a repetition operator, e.g., with `((a*)*(b*)*)*'
+			   against `aba'; then we want to ignore where we are now in
+			   the string in case this attempt to match fails.  */
+			old_regend[*p] = REG_MATCH_NULL_STRING_P(reg_info[*p])
+				? REG_UNSET(regend[*p]) ? d : regend[*p]
+				: regend[*p];
+			DEBUG_PRINT2("      old_regend: %d\n",
+						 POINTER_TO_OFFSET(old_regend[*p]));
+
+			regend[*p] = d;
+			DEBUG_PRINT2("      regend: %d\n",
+						 POINTER_TO_OFFSET(regend[*p]));
+
+			/* This register isn't active anymore.  */
+			IS_ACTIVE(reg_info[*p]) = 0;
+
+			/* Clear this whenever we change the register activity status.  */
+			set_regs_matched_done = 0;
+
+			/* If this was the only register active, nothing is active
+			   anymore.  */
+			if (lowest_active_reg == highest_active_reg) {
+				lowest_active_reg = NO_LOWEST_ACTIVE_REG;
+				highest_active_reg = NO_HIGHEST_ACTIVE_REG;
+			} else {			/* We must scan for the new highest active register, since
+								   it isn't necessarily one less than now: consider
+								   (a(b)c(d(e)f)g).  When group 3 ends, after the f), the
+								   new highest active register is 1.  */
+				unsigned char r = *p - 1;
+
+				while (r > 0 && !IS_ACTIVE(reg_info[r]))
+					r--;
+
+				/* If we end up at register zero, that means that we saved
+				   the registers as the result of an `on_failure_jump', not
+				   a `start_memory', and we jumped to past the innermost
+				   `stop_memory'.  For example, in ((.)*) we save
+				   registers 1 and 2 as a result of the *, but when we pop
+				   back to the second ), we are at the stop_memory 1.
+				   Thus, nothing is active.  */
+				if (r == 0) {
+					lowest_active_reg = NO_LOWEST_ACTIVE_REG;
+					highest_active_reg = NO_HIGHEST_ACTIVE_REG;
+				} else
+					highest_active_reg = r;
+			}
+
+			/* If just failed to match something this time around with a
+			   group that's operated on by a repetition operator, try to
+			   force exit from the ``loop'', and restore the register
+			   information for this group that we had before trying this
+			   last match.  */
+			if ((!MATCHED_SOMETHING(reg_info[*p])
+				 || just_past_start_mem == p - 1)
+				&& (p + 2) < pend) {
+				boolean is_a_jump_n = false;
+
+				p1 = p + 2;
+				mcnt = 0;
+				switch ((re_opcode_t) * p1++) {
+				case jump_n:
+					is_a_jump_n = true;
+				case pop_failure_jump:
+				case maybe_pop_jump:
+				case jump:
+				case dummy_failure_jump:
+					EXTRACT_NUMBER_AND_INCR(mcnt, p1);
+					if (is_a_jump_n)
+						p1 += 2;
+					break;
+
+				default:
+					/* do nothing */ ;
+				}
+				p1 += mcnt;
+
+				/* If the next operation is a jump backwards in the pattern
+				   to an on_failure_jump right before the start_memory
+				   corresponding to this stop_memory, exit from the loop
+				   by forcing a failure after pushing on the stack the
+				   on_failure_jump's jump in the pattern, and d.  */
+				if (mcnt < 0 && (re_opcode_t) * p1 == on_failure_jump
+					&& (re_opcode_t) p1[3] == start_memory && p1[4] == *p) {
+					/* If this group ever matched anything, then restore
+					   what its registers were before trying this last
+					   failed match, e.g., with `(a*)*b' against `ab' for
+					   regstart[1], and, e.g., with `((a*)*(b*)*)*'
+					   against `aba' for regend[3].
+
+					   Also restore the registers for inner groups for,
+					   e.g., `((a*)(b*))*' against `aba' (register 3 would
+					   otherwise get trashed).  */
+
+					if (EVER_MATCHED_SOMETHING(reg_info[*p])) {
+						unsigned r;
+
+						EVER_MATCHED_SOMETHING(reg_info[*p]) = 0;
+
+						/* Restore this and inner groups' (if any) registers.  */
+						for (r = *p;
+							 r < (unsigned) *p + (unsigned) *(p + 1); r++) {
+							regstart[r] = old_regstart[r];
+
+							/* xx why this test?  */
+							if (old_regend[r] >= regstart[r])
+								regend[r] = old_regend[r];
+						}
+					}
+					p1++;
+					EXTRACT_NUMBER_AND_INCR(mcnt, p1);
+					PUSH_FAILURE_POINT(p1 + mcnt, d, -2);
+
+					goto fail;
+				}
+			}
+
+			/* Move past the register number and the inner group count.  */
+			p += 2;
+			break;
+
+
+			/* \<digit> has been turned into a `duplicate' command which is
+			   followed by the numeric value of <digit> as the register number.  */
+		case duplicate:
+		{
+			register const char *d2, *dend2;
+			int regno = *p++;	/* Get which register to match against.  */
+
+			DEBUG_PRINT2("EXECUTING duplicate %d.\n", regno);
+
+			/* Can't back reference a group which we've never matched.  */
+			if (REG_UNSET(regstart[regno]) || REG_UNSET(regend[regno]))
+				goto fail;
+
+			/* Where in input to try to start matching.  */
+			d2 = regstart[regno];
+
+			/* Where to stop matching; if both the place to start and
+			   the place to stop matching are in the same string, then
+			   set to the place to stop, otherwise, for now have to use
+			   the end of the first string.  */
+
+			dend2 = ((FIRST_STRING_P(regstart[regno])
+					  == FIRST_STRING_P(regend[regno]))
+					 ? regend[regno] : end_match_1);
+			for (;;) {
+				/* If necessary, advance to next segment in register
+				   contents.  */
+				while (d2 == dend2) {
+					if (dend2 == end_match_2)
+						break;
+					if (dend2 == regend[regno])
+						break;
+
+					/* End of string1 => advance to string2. */
+					d2 = string2;
+					dend2 = regend[regno];
+				}
+				/* At end of register contents => success */
+				if (d2 == dend2)
+					break;
+
+				/* If necessary, advance to next segment in data.  */
+				PREFETCH();
+
+				/* How many characters left in this segment to match.  */
+				mcnt = dend - d;
+
+				/* Want how many consecutive characters we can match in
+				   one shot, so, if necessary, adjust the count.  */
+				if (mcnt > dend2 - d2)
+					mcnt = dend2 - d2;
+
+				/* Compare that many; failure if mismatch, else move
+				   past them.  */
+				if (translate ? bcmp_translate(d, d2, mcnt, translate)
+					: memcmp(d, d2, mcnt))
+					goto fail;
+				d += mcnt, d2 += mcnt;
+
+				/* Do this because we've match some characters.  */
+				SET_REGS_MATCHED();
+			}
+		}
+			break;
+
+
+			/* begline matches the empty string at the beginning of the string
+			   (unless `not_bol' is set in `bufp'), and, if
+			   `newline_anchor' is set, after newlines.  */
+		case begline:
+			DEBUG_PRINT1("EXECUTING begline.\n");
+
+			if (AT_STRINGS_BEG(d)) {
+				if (!bufp->not_bol)
+					break;
+			} else if (d[-1] == '\n' && bufp->newline_anchor) {
+				break;
+			}
+			/* In all other cases, we fail.  */
+			goto fail;
+
+
+			/* endline is the dual of begline.  */
+		case endline:
+			DEBUG_PRINT1("EXECUTING endline.\n");
+
+			if (AT_STRINGS_END(d)) {
+				if (!bufp->not_eol)
+					break;
+			}
+
+			/* We have to ``prefetch'' the next character.  */
+			else if ((d == end1 ? *string2 : *d) == '\n'
+					 && bufp->newline_anchor) {
+				break;
+			}
+			goto fail;
+
+
+			/* Match at the very beginning of the data.  */
+		case begbuf:
+			DEBUG_PRINT1("EXECUTING begbuf.\n");
+			if (AT_STRINGS_BEG(d))
+				break;
+			goto fail;
+
+
+			/* Match at the very end of the data.  */
+		case endbuf:
+			DEBUG_PRINT1("EXECUTING endbuf.\n");
+			if (AT_STRINGS_END(d))
+				break;
+			goto fail;
+
+
+			/* on_failure_keep_string_jump is used to optimize `.*\n'.  It
+			   pushes NULL as the value for the string on the stack.  Then
+			   `pop_failure_point' will keep the current value for the
+			   string, instead of restoring it.  To see why, consider
+			   matching `foo\nbar' against `.*\n'.  The .* matches the foo;
+			   then the . fails against the \n.  But the next thing we want
+			   to do is match the \n against the \n; if we restored the
+			   string value, we would be back at the foo.
+
+			   Because this is used only in specific cases, we don't need to
+			   check all the things that `on_failure_jump' does, to make
+			   sure the right things get saved on the stack.  Hence we don't
+			   share its code.  The only reason to push anything on the
+			   stack at all is that otherwise we would have to change
+			   `anychar's code to do something besides goto fail in this
+			   case; that seems worse than this.  */
+		case on_failure_keep_string_jump:
+			DEBUG_PRINT1("EXECUTING on_failure_keep_string_jump");
+
+			EXTRACT_NUMBER_AND_INCR(mcnt, p);
+#ifdef _LIBC
+			DEBUG_PRINT3(" %d (to %p):\n", mcnt, p + mcnt);
+#else
+			DEBUG_PRINT3(" %d (to 0x%x):\n", mcnt, p + mcnt);
+#endif
+
+			PUSH_FAILURE_POINT(p + mcnt, NULL, -2);
+			break;
+
+
+			/* Uses of on_failure_jump:
+
+			   Each alternative starts with an on_failure_jump that points
+			   to the beginning of the next alternative.  Each alternative
+			   except the last ends with a jump that in effect jumps past
+			   the rest of the alternatives.  (They really jump to the
+			   ending jump of the following alternative, because tensioning
+			   these jumps is a hassle.)
+
+			   Repeats start with an on_failure_jump that points past both
+			   the repetition text and either the following jump or
+			   pop_failure_jump back to this on_failure_jump.  */
+		case on_failure_jump:
+		  on_failure:
+			DEBUG_PRINT1("EXECUTING on_failure_jump");
+
+			EXTRACT_NUMBER_AND_INCR(mcnt, p);
+#ifdef _LIBC
+			DEBUG_PRINT3(" %d (to %p)", mcnt, p + mcnt);
+#else
+			DEBUG_PRINT3(" %d (to 0x%x)", mcnt, p + mcnt);
+#endif
+
+			/* If this on_failure_jump comes right before a group (i.e.,
+			   the original * applied to a group), save the information
+			   for that group and all inner ones, so that if we fail back
+			   to this point, the group's information will be correct.
+			   For example, in \(a*\)*\1, we need the preceding group,
+			   and in \(zz\(a*\)b*\)\2, we need the inner group.  */
+
+			/* We can't use `p' to check ahead because we push
+			   a failure point to `p + mcnt' after we do this.  */
+			p1 = p;
+
+			/* We need to skip no_op's before we look for the
+			   start_memory in case this on_failure_jump is happening as
+			   the result of a completed succeed_n, as in \(a\)\{1,3\}b\1
+			   against aba.  */
+			while (p1 < pend && (re_opcode_t) * p1 == no_op)
+				p1++;
+
+			if (p1 < pend && (re_opcode_t) * p1 == start_memory) {
+				/* We have a new highest active register now.  This will
+				   get reset at the start_memory we are about to get to,
+				   but we will have saved all the registers relevant to
+				   this repetition op, as described above.  */
+				highest_active_reg = *(p1 + 1) + *(p1 + 2);
+				if (lowest_active_reg == NO_LOWEST_ACTIVE_REG)
+					lowest_active_reg = *(p1 + 1);
+			}
+
+			DEBUG_PRINT1(":\n");
+			PUSH_FAILURE_POINT(p + mcnt, d, -2);
+			break;
+
+
+			/* A smart repeat ends with `maybe_pop_jump'.
+			   We change it to either `pop_failure_jump' or `jump'.  */
+		case maybe_pop_jump:
+			EXTRACT_NUMBER_AND_INCR(mcnt, p);
+			DEBUG_PRINT2("EXECUTING maybe_pop_jump %d.\n", mcnt);
+			{
+				register unsigned char *p2 = p;
+
+				/* Compare the beginning of the repeat with what in the
+				   pattern follows its end. If we can establish that there
+				   is nothing that they would both match, i.e., that we
+				   would have to backtrack because of (as in, e.g., `a*a')
+				   then we can change to pop_failure_jump, because we'll
+				   never have to backtrack.
+
+				   This is not true in the case of alternatives: in
+				   `(a|ab)*' we do need to backtrack to the `ab' alternative
+				   (e.g., if the string was `ab').  But instead of trying to
+				   detect that here, the alternative has put on a dummy
+				   failure point which is what we will end up popping.  */
+
+				/* Skip over open/close-group commands.
+				   If what follows this loop is a ...+ construct,
+				   look at what begins its body, since we will have to
+				   match at least one of that.  */
+				while (1) {
+					if (p2 + 2 < pend
+						&& ((re_opcode_t) * p2 == stop_memory
+							|| (re_opcode_t) * p2 == start_memory))
+						p2 += 3;
+					else if (p2 + 6 < pend
+							 && (re_opcode_t) * p2 == dummy_failure_jump)
+							p2 += 6;
+					else
+						break;
+				}
+
+				p1 = p + mcnt;
+				/* p1[0] ... p1[2] are the `on_failure_jump' corresponding
+				   to the `maybe_finalize_jump' of this case.  Examine what
+				   follows.  */
+
+				/* If we're at the end of the pattern, we can change.  */
+				if (p2 == pend) {
+					/* Consider what happens when matching ":\(.*\)"
+					   against ":/".  I don't really understand this code
+					   yet.  */
+					p[-3] = (unsigned char) pop_failure_jump;
+					DEBUG_PRINT1
+						("  End of pattern: change to `pop_failure_jump'.\n");
+				}
+
+				else if ((re_opcode_t) * p2 == exactn
+						 || (bufp->newline_anchor
+							 && (re_opcode_t) * p2 == endline)) {
+					register unsigned char c =
+						*p2 == (unsigned char) endline ? '\n' : p2[2];
+
+					if ((re_opcode_t) p1[3] == exactn && p1[5] != c) {
+						p[-3] = (unsigned char) pop_failure_jump;
+						DEBUG_PRINT3("  %c != %c => pop_failure_jump.\n",
+									 c, p1[5]);
+					}
+
+					else if ((re_opcode_t) p1[3] == charset
+							 || (re_opcode_t) p1[3] == charset_not) {
+						int not = (re_opcode_t) p1[3] == charset_not;
+
+						if (c < (unsigned char) (p1[4] * BYTEWIDTH)
+							&& p1[5 +
+								  c / BYTEWIDTH] & (1 << (c %
+														  BYTEWIDTH))) not
+								= !not;
+
+						/* `not' is equal to 1 if c would match, which means
+						   that we can't change to pop_failure_jump.  */
+						if (!not) {
+							p[-3] = (unsigned char) pop_failure_jump;
+							DEBUG_PRINT1
+								("  No match => pop_failure_jump.\n");
+						}
+					}
+				} else if ((re_opcode_t) * p2 == charset) {
+					/* We win if the first character of the loop is not part
+					   of the charset.  */
+					if ((re_opcode_t) p1[3] == exactn
+						&& !((int) p2[1] * BYTEWIDTH > (int) p1[5]
+							 && (p2[2 + p1[5] / BYTEWIDTH]
+								 & (1 << (p1[5] % BYTEWIDTH))))) {
+						p[-3] = (unsigned char) pop_failure_jump;
+						DEBUG_PRINT1("  No match => pop_failure_jump.\n");
+					}
+
+					else if ((re_opcode_t) p1[3] == charset_not) {
+						int idx;
+
+						/* We win if the charset_not inside the loop
+						   lists every character listed in the charset after.  */
+						for (idx = 0; idx < (int) p2[1]; idx++)
+							if (!(p2[2 + idx] == 0 || (idx < (int) p1[4]
+													   &&
+													   ((p2
+														 [2 +
+														  idx] & ~p1[5 +
+																	 idx])
+														== 0))))
+								break;
+
+						if (idx == p2[1]) {
+							p[-3] = (unsigned char) pop_failure_jump;
+							DEBUG_PRINT1
+								("  No match => pop_failure_jump.\n");
+						}
+					} else if ((re_opcode_t) p1[3] == charset) {
+						int idx;
+
+						/* We win if the charset inside the loop
+						   has no overlap with the one after the loop.  */
+						for (idx = 0;
+							 idx < (int) p2[1] && idx < (int) p1[4]; idx++)
+							if ((p2[2 + idx] & p1[5 + idx]) != 0)
+								break;
+
+						if (idx == p2[1] || idx == p1[4]) {
+							p[-3] = (unsigned char) pop_failure_jump;
+							DEBUG_PRINT1
+								("  No match => pop_failure_jump.\n");
+						}
+					}
+				}
+			}
+			p -= 2;				/* Point at relative address again.  */
+			if ((re_opcode_t) p[-1] != pop_failure_jump) {
+				p[-1] = (unsigned char) jump;
+				DEBUG_PRINT1("  Match => jump.\n");
+				goto unconditional_jump;
+			}
+			/* Note fall through.  */
+
+
+			/* The end of a simple repeat has a pop_failure_jump back to
+			   its matching on_failure_jump, where the latter will push a
+			   failure point.  The pop_failure_jump takes off failure
+			   points put on by this pop_failure_jump's matching
+			   on_failure_jump; we got through the pattern to here from the
+			   matching on_failure_jump, so didn't fail.  */
+		case pop_failure_jump:
+		{
+			/* We need to pass separate storage for the lowest and
+			   highest registers, even though we don't care about the
+			   actual values.  Otherwise, we will restore only one
+			   register from the stack, since lowest will == highest in
+			   `pop_failure_point'.  */
+			active_reg_t dummy_low_reg, dummy_high_reg;
+			unsigned char *pdummy;
+			const char *sdummy;
+
+			DEBUG_PRINT1("EXECUTING pop_failure_jump.\n");
+			POP_FAILURE_POINT(sdummy, pdummy,
+							  dummy_low_reg, dummy_high_reg,
+							  reg_dummy, reg_dummy, reg_info_dummy);
+		}
+			/* Note fall through.  */
+
+		  unconditional_jump:
+#ifdef _LIBC
+			DEBUG_PRINT2("\n%p: ", p);
+#else
+			DEBUG_PRINT2("\n0x%x: ", p);
+#endif
+			/* Note fall through.  */
+
+			/* Unconditionally jump (without popping any failure points).  */
+		case jump:
+			EXTRACT_NUMBER_AND_INCR(mcnt, p);	/* Get the amount to jump.  */
+			DEBUG_PRINT2("EXECUTING jump %d ", mcnt);
+			p += mcnt;			/* Do the jump.  */
+#ifdef _LIBC
+			DEBUG_PRINT2("(to %p).\n", p);
+#else
+			DEBUG_PRINT2("(to 0x%x).\n", p);
+#endif
+			break;
+
+
+			/* We need this opcode so we can detect where alternatives end
+			   in `group_match_null_string_p' et al.  */
+		case jump_past_alt:
+			DEBUG_PRINT1("EXECUTING jump_past_alt.\n");
+			goto unconditional_jump;
+
+
+			/* Normally, the on_failure_jump pushes a failure point, which
+			   then gets popped at pop_failure_jump.  We will end up at
+			   pop_failure_jump, also, and with a pattern of, say, `a+', we
+			   are skipping over the on_failure_jump, so we have to push
+			   something meaningless for pop_failure_jump to pop.  */
+		case dummy_failure_jump:
+			DEBUG_PRINT1("EXECUTING dummy_failure_jump.\n");
+			/* It doesn't matter what we push for the string here.  What
+			   the code at `fail' tests is the value for the pattern.  */
+			PUSH_FAILURE_POINT(NULL, NULL, -2);
+			goto unconditional_jump;
+
+
+			/* At the end of an alternative, we need to push a dummy failure
+			   point in case we are followed by a `pop_failure_jump', because
+			   we don't want the failure point for the alternative to be
+			   popped.  For example, matching `(a|ab)*' against `aab'
+			   requires that we match the `ab' alternative.  */
+		case push_dummy_failure:
+			DEBUG_PRINT1("EXECUTING push_dummy_failure.\n");
+			/* See comments just above at `dummy_failure_jump' about the
+			   two zeroes.  */
+			PUSH_FAILURE_POINT(NULL, NULL, -2);
+			break;
+
+			/* Have to succeed matching what follows at least n times.
+			   After that, handle like `on_failure_jump'.  */
+		case succeed_n:
+			EXTRACT_NUMBER(mcnt, p + 2);
+			DEBUG_PRINT2("EXECUTING succeed_n %d.\n", mcnt);
+
+			assert(mcnt >= 0);
+			/* Originally, this is how many times we HAVE to succeed.  */
+			if (mcnt > 0) {
+				mcnt--;
+				p += 2;
+				STORE_NUMBER_AND_INCR(p, mcnt);
+#ifdef _LIBC
+				DEBUG_PRINT3("  Setting %p to %d.\n", p - 2, mcnt);
+#else
+				DEBUG_PRINT3("  Setting 0x%x to %d.\n", p - 2, mcnt);
+#endif
+			} else if (mcnt == 0) {
+#ifdef _LIBC
+				DEBUG_PRINT2("  Setting two bytes from %p to no_op.\n",
+							 p + 2);
+#else
+				DEBUG_PRINT2("  Setting two bytes from 0x%x to no_op.\n",
+							 p + 2);
+#endif
+				p[2] = (unsigned char) no_op;
+				p[3] = (unsigned char) no_op;
+				goto on_failure;
+			}
+			break;
+
+		case jump_n:
+			EXTRACT_NUMBER(mcnt, p + 2);
+			DEBUG_PRINT2("EXECUTING jump_n %d.\n", mcnt);
+
+			/* Originally, this is how many times we CAN jump.  */
+			if (mcnt) {
+				mcnt--;
+				STORE_NUMBER(p + 2, mcnt);
+#ifdef _LIBC
+				DEBUG_PRINT3("  Setting %p to %d.\n", p + 2, mcnt);
+#else
+				DEBUG_PRINT3("  Setting 0x%x to %d.\n", p + 2, mcnt);
+#endif
+				goto unconditional_jump;
+			}
+			/* If don't have to jump any more, skip over the rest of command.  */
+			else
+				p += 4;
+			break;
+
+		case set_number_at:
+		{
+			DEBUG_PRINT1("EXECUTING set_number_at.\n");
+
+			EXTRACT_NUMBER_AND_INCR(mcnt, p);
+			p1 = p + mcnt;
+			EXTRACT_NUMBER_AND_INCR(mcnt, p);
+#ifdef _LIBC
+			DEBUG_PRINT3("  Setting %p to %d.\n", p1, mcnt);
+#else
+			DEBUG_PRINT3("  Setting 0x%x to %d.\n", p1, mcnt);
+#endif
+			STORE_NUMBER(p1, mcnt);
+			break;
+		}
+
+#if 0
+			/* The DEC Alpha C compiler 3.x generates incorrect code for the
+			   test  WORDCHAR_P (d - 1) != WORDCHAR_P (d)  in the expansion of
+			   AT_WORD_BOUNDARY, so this code is disabled.  Expanding the
+			   macro and introducing temporary variables works around the bug.  */
+
+		case wordbound:
+			DEBUG_PRINT1("EXECUTING wordbound.\n");
+			if (AT_WORD_BOUNDARY(d))
+				break;
+			goto fail;
+
+		case notwordbound:
+			DEBUG_PRINT1("EXECUTING notwordbound.\n");
+			if (AT_WORD_BOUNDARY(d))
+				goto fail;
+			break;
+#else
+		case wordbound:
+		{
+			boolean prevchar, thischar;
+
+			DEBUG_PRINT1("EXECUTING wordbound.\n");
+			if (AT_STRINGS_BEG(d) || AT_STRINGS_END(d))
+				break;
+
+			prevchar = WORDCHAR_P(d - 1);
+			thischar = WORDCHAR_P(d);
+			if (prevchar != thischar)
+				break;
+			goto fail;
+		}
+
+		case notwordbound:
+		{
+			boolean prevchar, thischar;
+
+			DEBUG_PRINT1("EXECUTING notwordbound.\n");
+			if (AT_STRINGS_BEG(d) || AT_STRINGS_END(d))
+				goto fail;
+
+			prevchar = WORDCHAR_P(d - 1);
+			thischar = WORDCHAR_P(d);
+			if (prevchar != thischar)
+				goto fail;
+			break;
+		}
+#endif
+
+		case wordbeg:
+			DEBUG_PRINT1("EXECUTING wordbeg.\n");
+			if (WORDCHAR_P(d) && (AT_STRINGS_BEG(d) || !WORDCHAR_P(d - 1)))
+				break;
+			goto fail;
+
+		case wordend:
+			DEBUG_PRINT1("EXECUTING wordend.\n");
+			if (!AT_STRINGS_BEG(d) && WORDCHAR_P(d - 1)
+				&& (!WORDCHAR_P(d) || AT_STRINGS_END(d)))
+				break;
+			goto fail;
+
+#ifdef emacs
+		case before_dot:
+			DEBUG_PRINT1("EXECUTING before_dot.\n");
+			if (PTR_CHAR_POS((unsigned char *) d) >= point)
+				goto fail;
+			break;
+
+		case at_dot:
+			DEBUG_PRINT1("EXECUTING at_dot.\n");
+			if (PTR_CHAR_POS((unsigned char *) d) != point)
+				goto fail;
+			break;
+
+		case after_dot:
+			DEBUG_PRINT1("EXECUTING after_dot.\n");
+			if (PTR_CHAR_POS((unsigned char *) d) <= point)
+				goto fail;
+			break;
+
+		case syntaxspec:
+			DEBUG_PRINT2("EXECUTING syntaxspec %d.\n", mcnt);
+			mcnt = *p++;
+			goto matchsyntax;
+
+		case wordchar:
+			DEBUG_PRINT1("EXECUTING Emacs wordchar.\n");
+			mcnt = (int) Sword;
+		  matchsyntax:
+			PREFETCH();
+			/* Can't use *d++ here; SYNTAX may be an unsafe macro.  */
+			d++;
+			if (SYNTAX(d[-1]) != (enum syntaxcode) mcnt)
+				goto fail;
+			SET_REGS_MATCHED();
+			break;
+
+		case notsyntaxspec:
+			DEBUG_PRINT2("EXECUTING notsyntaxspec %d.\n", mcnt);
+			mcnt = *p++;
+			goto matchnotsyntax;
+
+		case notwordchar:
+			DEBUG_PRINT1("EXECUTING Emacs notwordchar.\n");
+			mcnt = (int) Sword;
+		  matchnotsyntax:
+			PREFETCH();
+			/* Can't use *d++ here; SYNTAX may be an unsafe macro.  */
+			d++;
+			if (SYNTAX(d[-1]) == (enum syntaxcode) mcnt)
+				goto fail;
+			SET_REGS_MATCHED();
+			break;
+
+#else							/* not emacs */
+		case wordchar:
+			DEBUG_PRINT1("EXECUTING non-Emacs wordchar.\n");
+			PREFETCH();
+			if (!WORDCHAR_P(d))
+				goto fail;
+			SET_REGS_MATCHED();
+			d++;
+			break;
+
+		case notwordchar:
+			DEBUG_PRINT1("EXECUTING non-Emacs notwordchar.\n");
+			PREFETCH();
+			if (WORDCHAR_P(d))
+				goto fail;
+			SET_REGS_MATCHED();
+			d++;
+			break;
+#endif							/* not emacs */
+
+		default:
+			abort();
+		}
+		continue;				/* Successfully executed one pattern command; keep going.  */
+
+
+		/* We goto here if a matching operation fails. */
+	  fail:
+		if (!FAIL_STACK_EMPTY()) {	/* A restart point is known.  Restore to that state.  */
+			DEBUG_PRINT1("\nFAIL:\n");
+			POP_FAILURE_POINT(d, p,
+							  lowest_active_reg, highest_active_reg,
+							  regstart, regend, reg_info);
+
+			/* If this failure point is a dummy, try the next one.  */
+			if (!p)
+				goto fail;
+
+			/* If we failed to the end of the pattern, don't examine *p.  */
+			assert(p <= pend);
+			if (p < pend) {
+				boolean is_a_jump_n = false;
+
+				/* If failed to a backwards jump that's part of a repetition
+				   loop, need to pop this failure point and use the next one.  */
+				switch ((re_opcode_t) * p) {
+				case jump_n:
+					is_a_jump_n = true;
+				case maybe_pop_jump:
+				case pop_failure_jump:
+				case jump:
+					p1 = p + 1;
+					EXTRACT_NUMBER_AND_INCR(mcnt, p1);
+					p1 += mcnt;
+
+					if ((is_a_jump_n && (re_opcode_t) * p1 == succeed_n)
+						|| (!is_a_jump_n
+							&& (re_opcode_t) * p1 == on_failure_jump))
+							goto fail;
+					break;
+				default:
+					/* do nothing */ ;
+				}
+			}
+
+			if (d >= string1 && d <= end1)
+				dend = end_match_1;
+		} else
+			break;				/* Matching at this starting point really fails.  */
+	}							/* for (;;) */
+
+	if (best_regs_set)
+		goto restore_best_regs;
+
+	FREE_VARIABLES();
+
+	return -1;					/* Failure to match.  */
+}								/* re_match_2 */
+
+/* Subroutine definitions for re_match_2.  */
+
+
+/* We are passed P pointing to a register number after a start_memory.
+
+   Return true if the pattern up to the corresponding stop_memory can
+   match the empty string, and false otherwise.
+
+   If we find the matching stop_memory, sets P to point to one past its number.
+   Otherwise, sets P to an undefined byte less than or equal to END.
+
+   We don't handle duplicates properly (yet).  */
+
+static boolean group_match_null_string_p(p, end, reg_info)
+unsigned char **p, *end;
+register_info_type *reg_info;
+{
+	int mcnt;
+
+	/* Point to after the args to the start_memory.  */
+	unsigned char *p1 = *p + 2;
+
+	while (p1 < end) {
+		/* Skip over opcodes that can match nothing, and return true or
+		   false, as appropriate, when we get to one that can't, or to the
+		   matching stop_memory.  */
+
+		switch ((re_opcode_t) * p1) {
+			/* Could be either a loop or a series of alternatives.  */
+		case on_failure_jump:
+			p1++;
+			EXTRACT_NUMBER_AND_INCR(mcnt, p1);
+
+			/* If the next operation is not a jump backwards in the
+			   pattern.  */
+
+			if (mcnt >= 0) {
+				/* Go through the on_failure_jumps of the alternatives,
+				   seeing if any of the alternatives cannot match nothing.
+				   The last alternative starts with only a jump,
+				   whereas the rest start with on_failure_jump and end
+				   with a jump, e.g., here is the pattern for `a|b|c':
+
+				   /on_failure_jump/0/6/exactn/1/a/jump_past_alt/0/6
+				   /on_failure_jump/0/6/exactn/1/b/jump_past_alt/0/3
+				   /exactn/1/c
+
+				   So, we have to first go through the first (n-1)
+				   alternatives and then deal with the last one separately.  */
+
+
+				/* Deal with the first (n-1) alternatives, which start
+				   with an on_failure_jump (see above) that jumps to right
+				   past a jump_past_alt.  */
+
+				while ((re_opcode_t) p1[mcnt - 3] == jump_past_alt) {
+					/* `mcnt' holds how many bytes long the alternative
+					   is, including the ending `jump_past_alt' and
+					   its number.  */
+
+					if (!alt_match_null_string_p(p1, p1 + mcnt - 3,
+												 reg_info)) return false;
+
+					/* Move to right after this alternative, including the
+					   jump_past_alt.  */
+					p1 += mcnt;
+
+					/* Break if it's the beginning of an n-th alternative
+					   that doesn't begin with an on_failure_jump.  */
+					if ((re_opcode_t) * p1 != on_failure_jump)
+						break;
+
+					/* Still have to check that it's not an n-th
+					   alternative that starts with an on_failure_jump.  */
+					p1++;
+					EXTRACT_NUMBER_AND_INCR(mcnt, p1);
+					if ((re_opcode_t) p1[mcnt - 3] != jump_past_alt) {
+						/* Get to the beginning of the n-th alternative.  */
+						p1 -= 3;
+						break;
+					}
+				}
+
+				/* Deal with the last alternative: go back and get number
+				   of the `jump_past_alt' just before it.  `mcnt' contains
+				   the length of the alternative.  */
+				EXTRACT_NUMBER(mcnt, p1 - 2);
+
+				if (!alt_match_null_string_p(p1, p1 + mcnt, reg_info))
+					return false;
+
+				p1 += mcnt;		/* Get past the n-th alternative.  */
+			}					/* if mcnt > 0 */
+			break;
+
+
+		case stop_memory:
+			assert(p1[1] == **p);
+			*p = p1 + 2;
+			return true;
+
+
+		default:
+			if (!common_op_match_null_string_p(&p1, end, reg_info))
+				return false;
+		}
+	}							/* while p1 < end */
+
+	return false;
+}								/* group_match_null_string_p */
+
+
+/* Similar to group_match_null_string_p, but doesn't deal with alternatives:
+   It expects P to be the first byte of a single alternative and END one
+   byte past the last. The alternative can contain groups.  */
+
+static boolean alt_match_null_string_p(p, end, reg_info)
+unsigned char *p, *end;
+register_info_type *reg_info;
+{
+	int mcnt;
+	unsigned char *p1 = p;
+
+	while (p1 < end) {
+		/* Skip over opcodes that can match nothing, and break when we get
+		   to one that can't.  */
+
+		switch ((re_opcode_t) * p1) {
+			/* It's a loop.  */
+		case on_failure_jump:
+			p1++;
+			EXTRACT_NUMBER_AND_INCR(mcnt, p1);
+			p1 += mcnt;
+			break;
+
+		default:
+			if (!common_op_match_null_string_p(&p1, end, reg_info))
+				return false;
+		}
+	}							/* while p1 < end */
+
+	return true;
+}								/* alt_match_null_string_p */
+
+
+/* Deals with the ops common to group_match_null_string_p and
+   alt_match_null_string_p.
+
+   Sets P to one after the op and its arguments, if any.  */
+
+static boolean common_op_match_null_string_p(p, end, reg_info)
+unsigned char **p, *end;
+register_info_type *reg_info;
+{
+	int mcnt;
+	boolean ret;
+	int reg_no;
+	unsigned char *p1 = *p;
+
+	switch ((re_opcode_t) * p1++) {
+	case no_op:
+	case begline:
+	case endline:
+	case begbuf:
+	case endbuf:
+	case wordbeg:
+	case wordend:
+	case wordbound:
+	case notwordbound:
+#ifdef emacs
+	case before_dot:
+	case at_dot:
+	case after_dot:
+#endif
+		break;
+
+	case start_memory:
+		reg_no = *p1;
+		assert(reg_no > 0 && reg_no <= MAX_REGNUM);
+		ret = group_match_null_string_p(&p1, end, reg_info);
+
+		/* Have to set this here in case we're checking a group which
+		   contains a group and a back reference to it.  */
+
+		if (REG_MATCH_NULL_STRING_P(reg_info[reg_no]) ==
+			MATCH_NULL_UNSET_VALUE)
+				REG_MATCH_NULL_STRING_P(reg_info[reg_no]) = ret;
+
+		if (!ret)
+			return false;
+		break;
+
+		/* If this is an optimized succeed_n for zero times, make the jump.  */
+	case jump:
+		EXTRACT_NUMBER_AND_INCR(mcnt, p1);
+		if (mcnt >= 0)
+			p1 += mcnt;
+		else
+			return false;
+		break;
+
+	case succeed_n:
+		/* Get to the number of times to succeed.  */
+		p1 += 2;
+		EXTRACT_NUMBER_AND_INCR(mcnt, p1);
+
+		if (mcnt == 0) {
+			p1 -= 4;
+			EXTRACT_NUMBER_AND_INCR(mcnt, p1);
+			p1 += mcnt;
+		} else
+			return false;
+		break;
+
+	case duplicate:
+		if (!REG_MATCH_NULL_STRING_P(reg_info[*p1]))
+			return false;
+		break;
+
+	case set_number_at:
+		p1 += 4;
+
+	default:
+		/* All other opcodes mean we cannot match the empty string.  */
+		return false;
+	}
+
+	*p = p1;
+	return true;
+}								/* common_op_match_null_string_p */
+
+
+/* Return zero if TRANSLATE[S1] and TRANSLATE[S2] are identical for LEN
+   bytes; nonzero otherwise.  */
+
+static int bcmp_translate(s1, s2, len, translate)
+const char *s1, *s2;
+register int len;
+RE_TRANSLATE_TYPE translate;
+{
+	register const unsigned char *p1 = (const unsigned char *) s1;
+	register const unsigned char *p2 = (const unsigned char *) s2;
+
+	while (len) {
+		if (translate[*p1++] != translate[*p2++])
+			return 1;
+		len--;
+	}
+	return 0;
+}
+
+/* Entry points for GNU code.  */
+
+/* re_compile_pattern is the GNU regular expression compiler: it
+   compiles PATTERN (of length SIZE) and puts the result in BUFP.
+   Returns 0 if the pattern was valid, otherwise an error string.
+
+   Assumes the `allocated' (and perhaps `buffer') and `translate' fields
+   are set in BUFP on entry.
+
+   We call regex_compile to do the actual compilation.  */
+
+const char *re_compile_pattern(pattern, length, bufp)
+const char *pattern;
+size_t length;
+struct re_pattern_buffer *bufp;
+{
+	reg_errcode_t ret;
+
+	/* GNU code is written to assume at least RE_NREGS registers will be set
+	   (and at least one extra will be -1).  */
+	bufp->regs_allocated = REGS_UNALLOCATED;
+
+	/* And GNU code determines whether or not to get register information
+	   by passing null for the REGS argument to re_match, etc., not by
+	   setting no_sub.  */
+	bufp->no_sub = 0;
+
+	/* Match anchors at newline.  */
+	bufp->newline_anchor = 1;
+
+	ret = regex_compile(pattern, length, re_syntax_options, bufp);
+
+	if (!ret)
+		return NULL;
+	return gettext(re_error_msgid + re_error_msgid_idx[(int) ret]);
+}
+
+#ifdef _LIBC
+weak_alias(__re_compile_pattern, re_compile_pattern)
+#endif
+/* Entry points compatible with 4.2 BSD regex library.  We don't define
+   them unless specifically requested.  */
+#if defined _REGEX_RE_COMP || defined _LIBC
+/* BSD has one and only one pattern buffer.  */
+static struct re_pattern_buffer re_comp_buf;
+
+char *
+#ifdef _LIBC
+/* Make these definitions weak in libc, so POSIX programs can redefine
+   these names if they don't use our functions, and still use
+   regcomp/regexec below without link errors.  */ weak_function
+#endif
+re_comp(s)
+const char *s;
+{
+	reg_errcode_t ret;
+
+	if (!s) {
+		if (!re_comp_buf.buffer)
+			return gettext("No previous regular expression");
+		return 0;
+	}
+
+	if (!re_comp_buf.buffer) {
+		re_comp_buf.buffer = (unsigned char *) malloc(200);
+		if (re_comp_buf.buffer == NULL)
+			return (char *) gettext(re_error_msgid
+									+
+									re_error_msgid_idx[(int) REG_ESPACE]);
+		re_comp_buf.allocated = 200;
+
+		re_comp_buf.fastmap = (char *) malloc(1 << BYTEWIDTH);
+		if (re_comp_buf.fastmap == NULL)
+			return (char *) gettext(re_error_msgid
+									+
+									re_error_msgid_idx[(int) REG_ESPACE]);
+	}
+
+	/* Since `re_exec' always passes NULL for the `regs' argument, we
+	   don't need to initialize the pattern buffer fields which affect it.  */
+
+	/* Match anchors at newlines.  */
+	re_comp_buf.newline_anchor = 1;
+
+	ret = regex_compile(s, strlen(s), re_syntax_options, &re_comp_buf);
+
+	if (!ret)
+		return NULL;
+
+	/* Yes, we're discarding `const' here if !HAVE_LIBINTL.  */
+	return (char *) gettext(re_error_msgid +
+							re_error_msgid_idx[(int) ret]);
+}
+
+
+int
+#ifdef _LIBC
+ weak_function
+#endif
+re_exec(s)
+const char *s;
+{
+	const int len = strlen(s);
+
+	return
+		0 <= re_search(&re_comp_buf, s, len, 0, len,
+					   (struct re_registers *) 0);
+}
+
+#endif							/* _REGEX_RE_COMP */
+
+/* POSIX.2 functions.  Don't define these for Emacs.  */
+
+#ifndef emacs
+
+/* regcomp takes a regular expression as a string and compiles it.
+
+   PREG is a regex_t *.  We do not expect any fields to be initialized,
+   since POSIX says we shouldn't.  Thus, we set
+
+     `buffer' to the compiled pattern;
+     `used' to the length of the compiled pattern;
+     `syntax' to RE_SYNTAX_POSIX_EXTENDED if the
+       REG_EXTENDED bit in CFLAGS is set; otherwise, to
+       RE_SYNTAX_POSIX_BASIC;
+     `newline_anchor' to REG_NEWLINE being set in CFLAGS;
+     `fastmap' to an allocated space for the fastmap;
+     `fastmap_accurate' to zero;
+     `re_nsub' to the number of subexpressions in PATTERN.
+
+   PATTERN is the address of the pattern string.
+
+   CFLAGS is a series of bits which affect compilation.
+
+     If REG_EXTENDED is set, we use POSIX extended syntax; otherwise, we
+     use POSIX basic syntax.
+
+     If REG_NEWLINE is set, then . and [^...] don't match newline.
+     Also, regexec will try a match beginning after every newline.
+
+     If REG_ICASE is set, then we considers upper- and lowercase
+     versions of letters to be equivalent when matching.
+
+     If REG_NOSUB is set, then when PREG is passed to regexec, that
+     routine will report only success or failure, and nothing about the
+     registers.
+
+   It returns 0 if it succeeds, nonzero if it doesn't.  (See regex.h for
+   the return codes and their meanings.)  */
+
+int regcomp(preg, pattern, cflags)
+regex_t *preg;
+const char *pattern;
+int cflags;
+{
+	reg_errcode_t ret;
+	reg_syntax_t syntax
+		= (cflags & REG_EXTENDED) ?
+
+		RE_SYNTAX_POSIX_EXTENDED : RE_SYNTAX_POSIX_BASIC;
+
+	/* regex_compile will allocate the space for the compiled pattern.  */
+	preg->buffer = 0;
+	preg->allocated = 0;
+	preg->used = 0;
+
+	/* Try to allocate space for the fastmap.  */
+	preg->fastmap = (char *) malloc(1 << BYTEWIDTH);
+
+	if (cflags & REG_ICASE) {
+		unsigned i;
+
+		preg->translate
+			= (RE_TRANSLATE_TYPE) malloc(CHAR_SET_SIZE
+										 * sizeof(*(RE_TRANSLATE_TYPE) 0));
+		if (preg->translate == NULL)
+			return (int) REG_ESPACE;
+
+		/* Map uppercase characters to corresponding lowercase ones.  */
+		for (i = 0; i < CHAR_SET_SIZE; i++)
+			preg->translate[i] = ISUPPER(i) ? TOLOWER(i) : i;
+	} else
+		preg->translate = NULL;
+
+	/* If REG_NEWLINE is set, newlines are treated differently.  */
+	if (cflags & REG_NEWLINE) {	/* REG_NEWLINE implies neither . nor [^...] match newline.  */
+		syntax &= ~RE_DOT_NEWLINE;
+		syntax |= RE_HAT_LISTS_NOT_NEWLINE;
+		/* It also changes the matching behavior.  */
+		preg->newline_anchor = 1;
+	} else
+		preg->newline_anchor = 0;
+
+	preg->no_sub = !!(cflags & REG_NOSUB);
+
+	/* POSIX says a null character in the pattern terminates it, so we
+	   can use strlen here in compiling the pattern.  */
+	ret = regex_compile(pattern, strlen(pattern), syntax, preg);
+
+	/* POSIX doesn't distinguish between an unmatched open-group and an
+	   unmatched close-group: both are REG_EPAREN.  */
+	if (ret == REG_ERPAREN)
+		ret = REG_EPAREN;
+
+	if (ret == REG_NOERROR && preg->fastmap) {
+		/* Compute the fastmap now, since regexec cannot modify the pattern
+		   buffer.  */
+		if (re_compile_fastmap(preg) == -2) {
+			/* Some error occurred while computing the fastmap, just forget
+			   about it.  */
+			free(preg->fastmap);
+			preg->fastmap = NULL;
+		}
+	}
+
+	return (int) ret;
+}
+
+#ifdef _LIBC
+weak_alias(__regcomp, regcomp)
+#endif
+/* regexec searches for a given pattern, specified by PREG, in the
+   string STRING.
+
+   If NMATCH is zero or REG_NOSUB was set in the cflags argument to
+   `regcomp', we ignore PMATCH.  Otherwise, we assume PMATCH has at
+   least NMATCH elements, and we set them to the offsets of the
+   corresponding matched substrings.
+
+   EFLAGS specifies `execution flags' which affect matching: if
+   REG_NOTBOL is set, then ^ does not match at the beginning of the
+   string; if REG_NOTEOL is set, then $ does not match at the end.
+
+   We return 0 if we find a match and REG_NOMATCH if not.  */
+int regexec(preg, string, nmatch, pmatch, eflags)
+const regex_t *preg;
+const char *string;
+size_t nmatch;
+regmatch_t pmatch[];
+int eflags;
+{
+	int ret;
+	struct re_registers regs;
+	regex_t private_preg;
+	int len = strlen(string);
+	boolean want_reg_info = !preg->no_sub && nmatch > 0;
+
+	private_preg = *preg;
+
+	private_preg.not_bol = !!(eflags & REG_NOTBOL);
+	private_preg.not_eol = !!(eflags & REG_NOTEOL);
+
+	/* The user has told us exactly how many registers to return
+	   information about, via `nmatch'.  We have to pass that on to the
+	   matching routines.  */
+	private_preg.regs_allocated = REGS_FIXED;
+
+	if (want_reg_info) {
+		regs.num_regs = nmatch;
+		regs.start = TALLOC(nmatch * 2, regoff_t);
+		if (regs.start == NULL)
+			return (int) REG_NOMATCH;
+		regs.end = regs.start + nmatch;
+	}
+
+	/* Perform the searching operation.  */
+	ret = re_search(&private_preg, string, len,
+					/* start: */ 0, /* range: */ len,
+					want_reg_info ? &regs : (struct re_registers *) 0);
+
+	/* Copy the register information to the POSIX structure.  */
+	if (want_reg_info) {
+		if (ret >= 0) {
+			unsigned r;
+
+			for (r = 0; r < nmatch; r++) {
+				pmatch[r].rm_so = regs.start[r];
+				pmatch[r].rm_eo = regs.end[r];
+			}
+		}
+
+		/* If we needed the temporary register info, free the space now.  */
+		free(regs.start);
+	}
+
+	/* We want zero return to mean success, unlike `re_search'.  */
+	return ret >= 0 ? (int) REG_NOERROR : (int) REG_NOMATCH;
+}
+
+#ifdef _LIBC
+weak_alias(__regexec, regexec)
+#endif
+/* Returns a message corresponding to an error code, ERRCODE, returned
+   from either regcomp or regexec.   We don't use PREG here.  */
+	size_t regerror(errcode, preg, errbuf, errbuf_size)
+int errcode;
+const regex_t *preg;
+char *errbuf;
+size_t errbuf_size;
+{
+	const char *msg;
+	size_t msg_size;
+
+	if (errcode < 0 || errcode >= (int) (sizeof(re_error_msgid_idx)
+										 / sizeof(re_error_msgid_idx[0])))
+		/* Only error codes returned by the rest of the code should be passed
+		   to this routine.  If we are given anything else, or if other regex
+		   code generates an invalid error code, then the program has a bug.
+		   Dump core so we can fix it.  */
+		abort();
+
+	msg = gettext(re_error_msgid + re_error_msgid_idx[errcode]);
+
+	msg_size = strlen(msg) + 1;	/* Includes the null.  */
+
+	if (errbuf_size != 0) {
+		if (msg_size > errbuf_size) {
+#if defined HAVE_MEMPCPY || defined _LIBC
+			*((char *) __mempcpy(errbuf, msg, errbuf_size - 1)) = '\0';
+#else
+			memcpy(errbuf, msg, errbuf_size - 1);
+			errbuf[errbuf_size - 1] = 0;
+#endif
+		} else
+			memcpy(errbuf, msg, msg_size);
+	}
+
+	return msg_size;
+}
+
+#ifdef _LIBC
+weak_alias(__regerror, regerror)
+#endif
+/* Free dynamically allocated space used by PREG.  */
+void regfree(preg)
+regex_t *preg;
+{
+	if (preg->buffer != NULL)
+		free(preg->buffer);
+	preg->buffer = NULL;
+
+	preg->allocated = 0;
+	preg->used = 0;
+
+	if (preg->fastmap != NULL)
+		free(preg->fastmap);
+	preg->fastmap = NULL;
+	preg->fastmap_accurate = 0;
+
+	if (preg->translate != NULL)
+		free(preg->translate);
+	preg->translate = NULL;
+}
+
+#ifdef _LIBC
+weak_alias(__regfree, regfree)
+#endif
+#endif							/* not emacs  */