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-rw-r--r--gnulib/m4/stdbool.m4115
1 files changed, 115 insertions, 0 deletions
diff --git a/gnulib/m4/stdbool.m4 b/gnulib/m4/stdbool.m4
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+++ b/gnulib/m4/stdbool.m4
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+# Check for stdbool.h that conforms to C99.
+
+dnl Copyright (C) 2002-2006 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.
+
+AC_DEFUN([AM_STDBOOL_H],
+[
+ AC_REQUIRE([AC_HEADER_STDBOOL])
+
+ # Define two additional variables used in the Makefile substitution.
+
+ if test "$ac_cv_header_stdbool_h" = yes; then
+ STDBOOL_H=''
+ else
+ STDBOOL_H='stdbool.h'
+ fi
+ AC_SUBST([STDBOOL_H])
+
+ if test "$ac_cv_type__Bool" = yes; then
+ HAVE__BOOL=1
+ else
+ HAVE__BOOL=0
+ fi
+ 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 macro is only needed in autoconf <= 2.59. Newer versions of autoconf
+# have this macro built-in.
+
+AC_DEFUN([AC_HEADER_STDBOOL],
+ [AC_CACHE_CHECK([for stdbool.h that conforms to C99],
+ [ac_cv_header_stdbool_h],
+ [AC_TRY_COMPILE(
+ [
+ #include <stdbool.h>
+ #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];
+ bool e = &s;
+ 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 };
+ _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__ || defined __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. We also test
+ this with GCC, where it should work, to detect more
+ quickly whether someone messes up the test in the
+ future. */
+ char digs[] = "0123456789";
+ int xlcbug = 1 / (&(digs + 5)[-2 + (bool) 1] == &digs[4] ? 1 : -1);
+ #endif
+ /* 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;
+ ],
+ [
+ *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])
+ 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])