# Check for bool that conforms to C2023.
dnl Copyright 2022-2024 Free Software Foundation, 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.
AC_DEFUN([gl_C_BOOL],
[
AC_CACHE_CHECK([for bool, true, false], [gl_cv_c_bool],
[AC_COMPILE_IFELSE(
[AC_LANG_SOURCE([[
#if true == false
#error "true == false"
#endif
extern bool b;
bool b = true == false;]])],
[gl_cv_c_bool=yes],
[gl_cv_c_bool=no])])
if test "$gl_cv_c_bool" = yes; then
AC_DEFINE([HAVE_C_BOOL], [1],
[Define to 1 if bool, true and false work as per C2023.])
fi
AC_CHECK_HEADERS_ONCE([stdbool.h])
])