diff options
Diffstat (limited to 'm4/stdbool.m4')
| -rw-r--r-- | m4/stdbool.m4 | 124 |
1 files changed, 60 insertions, 64 deletions
diff --git a/m4/stdbool.m4 b/m4/stdbool.m4 index 3169779d4..c67908aa8 100644 --- a/m4/stdbool.m4 +++ b/m4/stdbool.m4 @@ -1,15 +1,15 @@ # Check for stdbool.h that conforms to C99. -dnl Copyright (C) 2002-2006, 2009-2021 Free Software Foundation, Inc. +dnl Copyright (C) 2002-2006, 2009-2022 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. -#serial 8 +#serial 9 # Prepare for substituting <stdbool.h> if it is not supported. -AC_DEFUN([AM_STDBOOL_H], +AC_DEFUN([gl_STDBOOL_H], [ AC_REQUIRE([AC_CHECK_HEADER_STDBOOL]) AC_REQUIRE([AC_CANONICAL_HOST]) @@ -22,20 +22,18 @@ AC_DEFUN([AM_STDBOOL_H], case "$host_os" in solaris*) if test -z "$GCC"; then - STDBOOL_H='stdbool.h' + GL_GENERATE_STDBOOL_H=true else - STDBOOL_H='' + GL_GENERATE_STDBOOL_H=false fi ;; *) - STDBOOL_H='' + GL_GENERATE_STDBOOL_H=false ;; esac else - STDBOOL_H='stdbool.h' + GL_GENERATE_STDBOOL_H=true fi - AC_SUBST([STDBOOL_H]) - AM_CONDITIONAL([GL_GENERATE_STDBOOL_H], [test -n "$STDBOOL_H"]) if test "$ac_cv_type__Bool" = yes; then HAVE__BOOL=1 @@ -45,78 +43,76 @@ AC_DEFUN([AM_STDBOOL_H], AC_SUBST([HAVE__BOOL]) ]) -# AM_STDBOOL_H will be renamed to gl_STDBOOL_H in the future. -AC_DEFUN([gl_STDBOOL_H], [AM_STDBOOL_H]) - -# This version of the macro is needed in autoconf <= 2.68. +m4_version_prereq([2.72], [], [ AC_DEFUN([AC_CHECK_HEADER_STDBOOL], - [AC_CACHE_CHECK([for stdbool.h that conforms to C99], + [AC_CHECK_TYPES([_Bool]) + AC_CACHE_CHECK([for stdbool.h that conforms to C99 or later], [ac_cv_header_stdbool_h], [AC_COMPILE_IFELSE( [AC_LANG_PROGRAM( - [[ - #include <stdbool.h> - - #ifdef __cplusplus - typedef bool Bool; - #else - typedef _Bool Bool; - #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: true is not defined" - #endif - #if true != 1 - "error: true is not 1" - #endif + [[#include <stdbool.h> + + /* "true" and "false" should be usable in #if expressions and + integer constant expressions, and "bool" should be a valid + type name. + + Although C 1999 requires bool, true, and false to be macros, + C 2023 and C++ 2011 overrule that, so do not test for that. + Although C 1999 requires __bool_true_false_are_defined and + _Bool, C 2023 says they are obsolescent, so do not require + them. */ + + #if !true + #error "'true' is not true" + #endif + #if true != 1 + #error "'true' is not equal to 1" #endif + char b[true == 1 ? 1 : -1]; + char c[true]; - #ifndef __bool_true_false_are_defined - "error: __bool_true_false_are_defined is not defined" + #if false + #error "'false' is not false" + #endif + #if false != 0 + #error "'false' is not equal to 0" #endif + char d[false == 0 ? 1 : -1]; + + enum { e = false, f = true, g = false * true, h = true * 256 }; + + char i[(bool) 0.5 == true ? 1 : -1]; + char j[(bool) 0.0 == false ? 1 : -1]; + char k[sizeof (bool) > 0 ? 1 : -1]; + + struct sb { bool s: 1; bool t; } s; + char l[sizeof s.t > 0 ? 1 : -1]; - struct s { Bool s: 1; Bool t; bool u: 1; bool v; } 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]; - /* See body of main program for 'e'. */ - char f[(Bool) 0.0 == false ? 1 : -1]; - char g[true]; - char h[sizeof (Bool)]; - char i[sizeof s.t]; - enum { j = false, k = true, l = false * true, m = true * 256 }; /* The following fails for HP aC++/ANSI C B3910B A.05.55 [Dec 04 2003]. */ - Bool n[m]; - char o[sizeof n == m * sizeof n[0] ? 1 : -1]; - char p[-1 - (Bool) 0 < 0 && -1 - (bool) 0 < 0 ? 1 : -1]; + bool m[h]; + char n[sizeof m == h * sizeof m[0] ? 1 : -1]; + char o[-1 - (bool) 0 < 0 ? 1 : -1]; /* Catch a bug in an HP-UX C compiler. See https://gcc.gnu.org/ml/gcc-patches/2003-12/msg02303.html https://lists.gnu.org/r/bug-coreutils/2005-11/msg00161.html */ - Bool q = true; - Bool *pq = &q; - bool *qq = &q; + bool p = true; + bool *pp = &p; ]], [[ - bool e = &s; - *pq |= q; *pq |= ! q; - *qq |= q; *qq |= ! q; - /* Refer to every declared value, to avoid compiler optimizations. */ - return (!a + !b + !c + !d + !e + !f + !g + !h + !i + !!j + !k + !!l - + !m + !n + !o + !p + !q + !pq + !qq); + bool ps = &s; + *pp |= p; + *pp |= ! p; + + /* Refer to every declared value, so they cannot be + discarded as unused. */ + return (!a + !b + !c + !d + !e + !f + !g + !h + !i + !j + !k + + !l + !m + !n + !o + !p + !pp + !ps); ]])], [ac_cv_header_stdbool_h=yes], [ac_cv_header_stdbool_h=no])]) - AC_CHECK_TYPES([_Bool]) -]) +])# AC_CHECK_HEADER_STDBOOL + +]) # m4_version_prereq 2.72 |