diff options
Diffstat (limited to 'm4/stdbool.m4')
| -rw-r--r-- | m4/stdbool.m4 | 57 |
1 files changed, 38 insertions, 19 deletions
diff --git a/m4/stdbool.m4 b/m4/stdbool.m4 index ed000c81..162f1dfc 100644 --- a/m4/stdbool.m4 +++ b/m4/stdbool.m4 @@ -1,21 +1,9 @@ # 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. +dnl Copyright (C) 2002-2005 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. # Prepare for substituting <stdbool.h> if it is not supported. @@ -40,7 +28,10 @@ AC_DEFUN([AM_STDBOOL_H], AC_SUBST([HAVE__BOOL]) ]) -# This macro is only needed in autoconf <= 2.54. Newer versions of autoconf +# AM_STDBOOL_H will be renamed to gl_STDBOOL_H in the future. +AC_DEFUN([gl_STDBOOL_H], [AM_STDBOOL_H]) + +# This macro is only needed in autoconf <= 2.59. Newer versions of autoconf # have this macro built-in. AC_DEFUN([AC_HEADER_STDBOOL], @@ -59,7 +50,7 @@ AC_DEFUN([AC_HEADER_STDBOOL], "error: false is not 0" #endif #ifndef true - "error: false is not defined" + "error: true is not defined" #endif #if true != 1 "error: true is not 1" @@ -79,8 +70,36 @@ AC_DEFUN([AC_HEADER_STDBOOL], char g[true]; char h[sizeof (_Bool)]; char i[sizeof s.t]; + enum { j = false, k = true, l = false * true, m = true * 256 }; + _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]; + #if defined __xlc__ || __GNUC__ + /* Catch a bug in IBM AIX xlc compiler version 6.0.0.0 + reported by James Lemley on 2005-10-05; see + <http://lists.gnu.org/archive/html/bug-coreutils/2005-10/msg00086.html>. + This test is not quite right, since xlc is allowed to + reject this program, as the initializer for xlcbug is + not one of the forms that C requires support for. + However, doing the test right would require a run-time + test, and that would make cross-compilation harder. + Let us hope that IBM fixes the xlc bug, and also adds + support for this kind of constant expression. In the + meantime, this test will reject xlc, which is OK, since + our stdbool.h substitute should suffice. */ + char digs[] = "0123456789"; + int xlcbug = 1 / (&(digs + 5)[-2 + (bool) 1] == &digs[4] ? 1 : -1); + #endif + _Bool q = true; + _Bool *pq = &q; + ], + [ + *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); ], - [ 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]) |