1# Check for stdbool.h that conforms to C99. 2 3dnl Copyright (C) 2002-2004 Free Software Foundation, Inc. 4dnl This file is free software; the Free Software Foundation 5dnl gives unlimited permission to copy and/or distribute it, 6dnl with or without modifications, as long as this notice is preserved. 7 8# Prepare for substituting <stdbool.h> if it is not supported. 9 10AC_DEFUN([AM_STDBOOL_H], 11[ 12 AC_REQUIRE([AC_HEADER_STDBOOL]) 13 14 # Define two additional variables used in the Makefile substitution. 15 16 if test "$ac_cv_header_stdbool_h" = yes; then 17 STDBOOL_H='' 18 else 19 STDBOOL_H='stdbool.h' 20 fi 21 AC_SUBST([STDBOOL_H]) 22 23 if test "$ac_cv_type__Bool" = yes; then 24 HAVE__BOOL=1 25 else 26 HAVE__BOOL=0 27 fi 28 AC_SUBST([HAVE__BOOL]) 29]) 30 31# This macro is only needed in autoconf <= 2.59. Newer versions of autoconf 32# have this macro built-in. 33 34AC_DEFUN([AC_HEADER_STDBOOL], 35 [AC_CACHE_CHECK([for stdbool.h that conforms to C99], 36 [ac_cv_header_stdbool_h], 37 [AC_TRY_COMPILE( 38 [ 39 #include <stdbool.h> 40 #ifndef bool 41 "error: bool is not defined" 42 #endif 43 #ifndef false 44 "error: false is not defined" 45 #endif 46 #if false 47 "error: false is not 0" 48 #endif 49 #ifndef true 50 "error: true is not defined" 51 #endif 52 #if true != 1 53 "error: true is not 1" 54 #endif 55 #ifndef __bool_true_false_are_defined 56 "error: __bool_true_false_are_defined is not defined" 57 #endif 58 59 struct s { _Bool s: 1; _Bool t; } s; 60 61 char a[true == 1 ? 1 : -1]; 62 char b[false == 0 ? 1 : -1]; 63 char c[__bool_true_false_are_defined == 1 ? 1 : -1]; 64 char d[(bool) -0.5 == true ? 1 : -1]; 65 bool e = &s; 66 char f[(_Bool) -0.0 == false ? 1 : -1]; 67 char g[true]; 68 char h[sizeof (_Bool)]; 69 char i[sizeof s.t]; 70 enum { j = false, k = true, l = false * true, m = true * 256 }; 71 _Bool n[m]; 72 char o[sizeof n == m * sizeof n[0] ? 1 : -1]; 73 ], 74 [ 75 return (!a + !b + !c + !d + !e + !f + !g + !h + !i + !j + !k + !l 76 + !m + !n + !o); 77 ], 78 [ac_cv_header_stdbool_h=yes], 79 [ac_cv_header_stdbool_h=no])]) 80 AC_CHECK_TYPES([_Bool]) 81 if test $ac_cv_header_stdbool_h = yes; then 82 AC_DEFINE(HAVE_STDBOOL_H, 1, [Define to 1 if stdbool.h conforms to C99.]) 83 fi]) 84