emacs/m4/glibc21.m4

# glibc21.m4 serial 5
dnl Copyright (C) 2000-2002, 2004, 2008, 2010-2018 Free Software Foundation,
dnl Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
dnl with or without modifications, as long as this notice is preserved.

# Test for the GNU C Library, version 2.1 or newer, or uClibc.
# From Bruno Haible.

AC_DEFUN([gl_GLIBC21],
  [
    AC_CACHE_CHECK([whether we are using the GNU C Library >= 2.1 or uClibc],
      [ac_cv_gnu_library_2_1],
      [AC_EGREP_CPP([Lucky],
        [
#include <features.h>
#ifdef __GNU_LIBRARY__
 #if (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 1) || (__GLIBC__ > 2)
  Lucky GNU user
 #endif
#endif
#ifdef __UCLIBC__
 Lucky user
#endif
        ],
        [ac_cv_gnu_library_2_1=yes],
        [ac_cv_gnu_library_2_1=no])
      ]
    )
    AC_SUBST([GLIBC21])
    GLIBC21="$ac_cv_gnu_library_2_1"
  ]
)
Use Gnulib regex for lib-src Emacs regular expressions forked from everyone else long ago. This makes it official and should allow simplification later. etags.c now uses the glibc regex API, falling back on a Gnulib-supplied substitute lib/regex.c if necessary. Emacs proper now uses its own regular expression module. Although this patch may look dauntingly large, most of it was generated automatically by admin/merge-gnulib and contains an exact copy of the glibc regex source, and the by-hand changes do not grow the Emacs source code. * admin/merge-gnulib (GNULIB_MODULES): Add regex. (AVOIDED_MODULES): Add btowc, langinfo, lock, mbrtowc, mbsinit, nl_langinfo, wchar, wcrtomb, wctype-h. * lib-src/Makefile.in (regex-emacs.o): Remove; Gnulib does it now. (etags_deps, etags_libs): Remove regex-emacs.o. * lib-src/etags.c: Go back to including regex.h. (add_regex): Use unsigned char translation array, since glibc regex requires that. * lib/Makefile.in (not_emacs_OBJECTS, for_emacs_OBJECTS): New macros. (libegnu_a_OBJECTS): Use them, to avoid building e-regex.o. * lib/gnulib.mk.in, m4/gnulib-comp.m4: Regenerate. * lib/regcomp.c, lib/regex.c, lib/regex.h, lib/regex_internal.c: * lib/regex_internal.h, lib/regexec.c, m4/builtin-expect.m4: * m4/eealloc.m4, m4/glibc21.m4, m4/mbstate_t.m4, m4/regex.m4: New files, copied from Gnulib. * src/regex-emacs.h, src/conf_post.h: (RE_TRANSLATE_TYPE, RE_TRANSLATE, RE_TRANSLATE_P): Move from src/conf_post.h to src/regex-emacs.h, so that they don’t interfere with compiling lib/regex.c. 2018-08-06 01:41:20 +00:00			`# glibc21.m4 serial 5`
			`dnl Copyright (C) 2000-2002, 2004, 2008, 2010-2018 Free Software Foundation,`
			`dnl Inc.`
			`dnl This file is free software; the Free Software Foundation`
			`dnl gives unlimited permission to copy and/or distribute it,`
			`dnl with or without modifications, as long as this notice is preserved.`

			`# Test for the GNU C Library, version 2.1 or newer, or uClibc.`
			`# From Bruno Haible.`

			`AC_DEFUN([gl_GLIBC21],`
			`[`
			`AC_CACHE_CHECK([whether we are using the GNU C Library >= 2.1 or uClibc],`
			`[ac_cv_gnu_library_2_1],`
			`[AC_EGREP_CPP([Lucky],`
			`[`
			`#include <features.h>`
			`#ifdef __GNU_LIBRARY__`
			`#if (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 1) \|\| (__GLIBC__ > 2)`
			`Lucky GNU user`
			`#endif`
			`#endif`
			`#ifdef __UCLIBC__`
			`Lucky user`
			`#endif`
			`],`
			`[ac_cv_gnu_library_2_1=yes],`
			`[ac_cv_gnu_library_2_1=no])`
			`]`
			`)`
			`AC_SUBST([GLIBC21])`
			`GLIBC21="$ac_cv_gnu_library_2_1"`
			`]`
			`)`