Header guard bug.

[bison.git] / m4 / c-bs-a.m4

# c-bs-a.m4 serial 4 (fileutils-4.1.3)
dnl Copyright (C) 2000-2002 Free Software Foundation, Inc.
dnl This file is free software, distributed under the terms of the GNU
dnl General Public License.  As a special exception to the GNU General
dnl Public License, this file may be distributed as part of a program
dnl that contains a configuration script generated by Autoconf, under
dnl the same distribution terms as the rest of that program.

dnl From Paul Eggert.

AC_DEFUN([AC_C_BACKSLASH_A],
[
  AC_CACHE_CHECK([whether backslash-a works in strings], ac_cv_c_backslash_a,
   [AC_TRY_COMPILE([],
     [
#if '\a' == 'a'
      syntax error;
#endif
      char buf['\a' == 'a' ? -1 : 1];
      buf[0] = '\a';
      return buf[0] != "\a"[0];
     ],
     ac_cv_c_backslash_a=yes,
     ac_cv_c_backslash_a=no)])
  if test $ac_cv_c_backslash_a = yes; then
    AC_DEFINE(HAVE_C_BACKSLASH_A, 1,
      [Define if backslash-a works in C strings.])
  fi
])