From: Paul Eggert Date: Sat, 5 Feb 2011 04:38:07 +0000 (-0800) Subject: autoconf: new macro AC_HEADER_CHECK_STDBOOL X-Git-Tag: v2.68b~110 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=46acbee4f8cb63d6656d2efd2025e6f99ee77e81;p=thirdparty%2Fautoconf.git autoconf: new macro AC_HEADER_CHECK_STDBOOL * NEWS: Document this. * doc/autoconf.texi (Particular Headers): Likewise. In example, don't assume a 'system.h' exists. * lib/autoconf/headers.m4 (AC_CHECK_HEADER_STDBOOL): New macro. Use it with AN_IDENTIFIER, since it's less heavyweight. Reindent to match gnulib, since that's a bit nicer. (AC_HEADER_STDBOOL): Reimplement in terms of it. --- diff --git a/ChangeLog b/ChangeLog index b36aab1d..6d654019 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,14 @@ +2011-02-04 Paul Eggert + + autoconf: new macro AC_HEADER_CHECK_STDBOOL + * NEWS: Document this. + * doc/autoconf.texi (Particular Headers): Likewise. + In example, don't assume a 'system.h' exists. + * lib/autoconf/headers.m4 (AC_CHECK_HEADER_STDBOOL): New macro. + Use it with AN_IDENTIFIER, since it's less heavyweight. + Reindent to match gnulib, since that's a bit nicer. + (AC_HEADER_STDBOOL): Reimplement in terms of it. + 2011-01-29 Jim Warhol (tiny change) * doc/autoconf.texi (Introduction): Fix typo. diff --git a/NEWS b/NEWS index d00c312a..c485f229 100644 --- a/NEWS +++ b/NEWS @@ -5,6 +5,9 @@ GNU Autoconf NEWS - User visible changes. ** AS_LITERAL_IF again treats '=' as a literal. Regression introduced in 2.66. +** Macros + +- New macro AC_HEADER_CHECK_STDBOOL. * Noteworthy changes in release 2.68 (2010-09-22) [stable] Released by Eric Blake, based on git versions 2.67.*. diff --git a/doc/autoconf.texi b/doc/autoconf.texi index b1ccb1af..6ad657e0 100644 --- a/doc/autoconf.texi +++ b/doc/autoconf.texi @@ -5811,6 +5811,21 @@ AC_CHECK_HEADERS([X11/extensions/scrnsaver.h], [], [], These macros check for particular system header files---whether they exist, and in some cases whether they declare certain symbols. +@defmac AC_CHECK_HEADER_STDBOOL +@acindex{CHECK_HEADER_STDBOOL} +@cvindex HAVE__BOOL +@hdrindex{stdbool.h} +@caindex header_stdbool_h +Check whether @file{stdbool.h} exists and conforms to C99, and cache the +result in the @code{ac_cv_header_stdbool_h} variable. If the type +@code{_Bool} is defined, define @code{HAVE__BOOL} to 1. + +This macro is intended for use by Gnulib (@pxref{Gnulib}) and other +packages that supply a substitute @file{stdbool.h} on platforms lacking +a conforming one. The @code{AC_HEADER_STDBOOL} macro is better for code +that explicitly checks for @file{stdbool.h}. +@end defmac + @defmac AC_HEADER_ASSERT @acindex{HEADER_ASSERT} @cvindex NDEBUG @@ -5937,14 +5952,14 @@ New programs need not use this macro. @cvindex HAVE_STDBOOL_H @cvindex HAVE__BOOL @hdrindex{stdbool.h} -@hdrindex{system.h} @caindex header_stdbool_h If @file{stdbool.h} exists and conforms to C99, define @code{HAVE_STDBOOL_H} to 1; if the type @code{_Bool} is defined, define @code{HAVE__BOOL} to 1. To fulfill the C99 requirements, your -@file{system.h} could contain the following code: +program could contain the following code: -@verbatim +@example +@group #ifdef HAVE_STDBOOL_H # include #else @@ -5960,14 +5975,20 @@ typedef bool _Bool; # define true 1 # define __bool_true_false_are_defined 1 #endif -@end verbatim +@end group +@end example Alternatively you can use the @samp{stdbool} package of Gnulib -(@pxref{Gnulib}); it packages the above code into a replacement header -and contains a few other bells and whistles. +(@pxref{Gnulib}). It simplifies your code so that it can say just +@code{#include }, and it adds support for less-common +platforms. This macro caches its result in the @code{ac_cv_header_stdbool_h} variable. + +This macro differs from @code{AC_CHECK_HEADER_STDBOOL} only in that it +defines @code{HAVE_STDBOOL_H} whereas @code{AC_CHECK_HEADER_STDBOOL} +does not. @end defmac @anchor{AC_HEADER_STDC} diff --git a/lib/autoconf/headers.m4 b/lib/autoconf/headers.m4 index 75bdfeff..4b028321 100644 --- a/lib/autoconf/headers.m4 +++ b/lib/autoconf/headers.m4 @@ -591,72 +591,81 @@ fi ])# AC_HEADER_STAT -# AC_HEADER_STDBOOL +# AC_CHECK_HEADER_STDBOOL # ----------------- # Check for stdbool.h that conforms to C99. -AN_IDENTIFIER([bool], [AC_HEADER_STDBOOL]) -AN_IDENTIFIER([true], [AC_HEADER_STDBOOL]) -AN_IDENTIFIER([false],[AC_HEADER_STDBOOL]) -AC_DEFUN([AC_HEADER_STDBOOL], -[AC_CACHE_CHECK([for stdbool.h that conforms to C99], - [ac_cv_header_stdbool_h], - [AC_COMPILE_IFELSE([AC_LANG_PROGRAM( - [[ -#include -#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 -#ifndef __bool_true_false_are_defined - "error: __bool_true_false_are_defined is not defined" -#endif +AN_IDENTIFIER([bool], [AC_CHECK_HEADER_STDBOOL]) +AN_IDENTIFIER([true], [AC_CHECK_HEADER_STDBOOL]) +AN_IDENTIFIER([false],[AC_CHECK_HEADER_STDBOOL]) +AC_DEFUN([AC_CHECK_HEADER_STDBOOL], + [AC_CACHE_CHECK([for stdbool.h that conforms to C99], + [ac_cv_header_stdbool_h], + [AC_COMPILE_IFELSE( + [AC_LANG_PROGRAM( + [[ + #include + #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 + #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]; + /* 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]; + /* Catch a bug in an HP-UX C compiler. See + http://gcc.gnu.org/ml/gcc-patches/2003-12/msg02303.html + http://lists.gnu.org/archive/html/bug-coreutils/2005-11/msg00161.html + */ + _Bool q = true; + _Bool *pq = &q; + ]], + [[ + bool e = &s; + *pq |= q; + *pq |= ! 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); + ]])], + [ac_cv_header_stdbool_h=yes], + [ac_cv_header_stdbool_h=no])]) + AC_CHECK_TYPES([_Bool]) +])# AC_CHECK_HEADER_STDBOOL + - 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]; - /* 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]; - /* Catch a bug in an HP-UX C compiler. See - http://gcc.gnu.org/ml/gcc-patches/2003-12/msg02303.html - http://lists.gnu.org/archive/html/bug-coreutils/2005-11/msg00161.html - */ - _Bool q = true; - _Bool *pq = &q; - ]], - [[ - bool e = &s; - *pq |= q; - *pq |= ! 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); - ]])], - [ac_cv_header_stdbool_h=yes], - [ac_cv_header_stdbool_h=no])]) -AC_CHECK_TYPES([_Bool]) +# AC_HEADER_STDBOOL +# ----------------- +# Define HAVE_STDBOOL_H if tdbool.h that conforms to C99. +AC_DEFUN([AC_HEADER_STDBOOL], +[AC_CHECK_HEADER_STDBOOL 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