diff options
Diffstat (limited to 'm4')
-rw-r--r-- | m4/stdbool.m4 | 89 |
1 files changed, 89 insertions, 0 deletions
diff --git a/m4/stdbool.m4 b/m4/stdbool.m4 new file mode 100644 index 00000000..ed000c81 --- /dev/null +++ b/m4/stdbool.m4 @@ -0,0 +1,89 @@ +# Check for stdbool.h that conforms to C99. + +# Copyright (C) 2002-2003 Free Software Foundation, Inc. + +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 2, or (at your option) +# any later version. + +# This program 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 General Public License for more details. + +# You should have received a copy of the GNU General Public License +# along with this program; if not, write to the Free Software +# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA +# 02111-1307, USA. + +# Prepare for substituting <stdbool.h> if it is not supported. + +AC_DEFUN([AM_STDBOOL_H], +[ + AC_REQUIRE([AC_HEADER_STDBOOL]) + + # Define two additional variables used in the Makefile substitution. + + if test "$ac_cv_header_stdbool_h" = yes; then + STDBOOL_H='' + else + STDBOOL_H='stdbool.h' + fi + AC_SUBST([STDBOOL_H]) + + if test "$ac_cv_type__Bool" = yes; then + HAVE__BOOL=1 + else + HAVE__BOOL=0 + fi + AC_SUBST([HAVE__BOOL]) +]) + +# This macro is only needed in autoconf <= 2.54. Newer versions of autoconf +# have this macro built-in. + +AC_DEFUN([AC_HEADER_STDBOOL], + [AC_CACHE_CHECK([for stdbool.h that conforms to C99], + [ac_cv_header_stdbool_h], + [AC_TRY_COMPILE( + [ + #include <stdbool.h> + #ifndef bool + "error: bool is not defined" + #endif + #ifndef false + "error: false is not defined" + #endif + #if false + "error: false is not 0" + #endif + #ifndef true + "error: false is not defined" + #endif + #if true != 1 + "error: true is not 1" + #endif + #ifndef __bool_true_false_are_defined + "error: __bool_true_false_are_defined is not defined" + #endif + + struct s { _Bool s: 1; _Bool t; } s; + + char a[true == 1 ? 1 : -1]; + char b[false == 0 ? 1 : -1]; + char c[__bool_true_false_are_defined == 1 ? 1 : -1]; + char d[(bool) -0.5 == true ? 1 : -1]; + bool e = &s; + char f[(_Bool) -0.0 == false ? 1 : -1]; + char g[true]; + char h[sizeof (_Bool)]; + char i[sizeof s.t]; + ], + [ return !a + !b + !c + !d + !e + !f + !g + !h + !i; ], + [ac_cv_header_stdbool_h=yes], + [ac_cv_header_stdbool_h=no])]) + AC_CHECK_TYPES([_Bool]) + if test $ac_cv_header_stdbool_h = yes; then + AC_DEFINE(HAVE_STDBOOL_H, 1, [Define to 1 if stdbool.h conforms to C99.]) + fi]) |