Avoid some autoconf warnings.

[gnulib.git] / m4 / regex.m4

diff --git a/m4/regex.m4 b/m4/regex.m4
index f694bac..656cef7 100644 (file)
--- a/m4/regex.m4
+++ b/m4/regex.m4
@@ -1,7 +1,7 @@
-#serial 44
+#serial 50
 
 # Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2003, 2004, 2005,
-# 2006, 2007 Free Software Foundation, Inc.
+# 2006, 2007, 2008 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -17,10 +17,13 @@ AC_DEFUN([gl_REGEX],
   AC_CHECK_HEADERS_ONCE([locale.h])
 
   AC_ARG_WITH([included-regex],
-    [AC_HELP_STRING([--without-included-regex],
-                   [don't compile regex; this is the default on
+    [AS_HELP_STRING([--without-included-regex],
+                   [don't compile regex; this is the default on 32-bit
                     systems with recent-enough versions of the GNU C
-                    Library (use with caution on other systems)])])
+                    Library (use with caution on other systems).
+                    On systems with 64-bit ptrdiff_t and 32-bit int,
+                    --with-included-regex is the default, in case
+                    regex functions operate on very long strings (>2GB)])])
 
   case $with_included_regex in #(
   yes|no) ac_use_included_regex=$with_included_regex
@@ -134,6 +137,17 @@ AC_DEFUN([gl_REGEX],
            if (re_search (&regex, "WXY", 3, 0, 3, &regs) < 0)
              return 1;
 
+           /* Catch a bug reported by Vin Shelton in
+              http://lists.gnu.org/archive/html/bug-coreutils/2007-06/msg00089.html
+              */
+           re_set_syntax (RE_SYNTAX_POSIX_BASIC
+                          & ~RE_CONTEXT_INVALID_DUP
+                          & ~RE_NO_EMPTY_RANGES);
+           memset (&regex, 0, sizeof regex);
+           s = re_compile_pattern ("[[:alnum:]_-]\\\\+$", 16, &regex);
+           if (s)
+             return 1;
+
            /* REG_STARTEND was added to glibc on 2004-01-15.
               Reject older versions.  */
            if (! REG_STARTEND)
@@ -201,9 +215,9 @@ AC_DEFUN([gl_REGEX],
 # Prerequisites of lib/regex.c and lib/regex_internal.c.
 AC_DEFUN([gl_PREREQ_REGEX],
 [
-  AC_REQUIRE([AC_GNU_SOURCE])
+  AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])
   AC_REQUIRE([AC_C_RESTRICT])
-  AC_REQUIRE([AM_LANGINFO_CODESET])
-  AC_CHECK_FUNCS_ONCE([iswctype mbrtowc wcrtomb wcscoll])
+  AC_REQUIRE([AC_TYPE_MBSTATE_T])
+  AC_CHECK_FUNCS_ONCE([isblank iswctype mbrtowc wcrtomb wcscoll])
   AC_CHECK_DECLS([isblank], [], [], [#include <ctype.h>])
 ])