view m4/vararrays.m4 @ 16768:cd4aba7fcd3e

New module 'ilogbl'. * lib/math.in.h (ilogbl): New declaration. * lib/ilogbl.c: New file. * m4/ilogbl.m4: New file. * m4/math_h.m4 (gl_MATH_H): Test whether ilogbl is declared. (gl_MATH_H_DEFAULTS): Initialize GNULIB_ILOGBL, HAVE_ILOGBL. * modules/math (Makefile.am): Substitute GNULIB_ILOGBL, HAVE_ILOGBL. Split sed invocation, to avoid the limit of 100 substitutions of HP-UX 'sed'. * modules/ilogbl: New file. * tests/test-math-c++.cc: Check the declaration of ilogbl. * doc/posix-functions/ilogbl.texi: Mention the new module.
author Bruno Haible <bruno@clisp.org>
date Tue, 03 Apr 2012 21:58:52 +0200
parents 8250f2777afc
children e542fd46ad6f
line wrap: on
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# Check for variable-length arrays.

# serial 4

# From Paul Eggert

# Copyright (C) 2001, 2009-2012 Free Software Foundation, Inc.
# This file is free software; the Free Software Foundation
# gives unlimited permission to copy and/or distribute it,
# with or without modifications, as long as this notice is preserved.

AC_DEFUN([AC_C_VARARRAYS],
[
  AC_CACHE_CHECK([for variable-length arrays],
    ac_cv_c_vararrays,
    [AC_COMPILE_IFELSE([AC_LANG_PROGRAM(
         [],
         [[static int x; char a[++x]; a[sizeof a - 1] = 0; return a[0];]])],
       ac_cv_c_vararrays=yes,
       ac_cv_c_vararrays=no)])
  if test $ac_cv_c_vararrays = yes; then
    AC_DEFINE([HAVE_C_VARARRAYS], [1],
      [Define to 1 if C supports variable-length arrays.])
  fi
])