source: trunk/m4/longlong.m4

Last change on this file was 1463, checked in by Peter Johansson, 9 years ago

set svncopyright:ignore property

  • Property svn:eol-style set to native
  • Property svn:keywords set to Id Date
File size: 4.0 KB
Line 
1# longlong.m4 serial 13
2dnl Copyright (C) 1999-2007 Free Software Foundation, Inc.
3dnl This file is free software; the Free Software Foundation
4dnl gives unlimited permission to copy and/or distribute it,
5dnl with or without modifications, as long as this notice is preserved.
6
7dnl From Paul Eggert.
8
9# Define HAVE_LONG_LONG_INT if 'long long int' works.
10# This fixes a bug in Autoconf 2.61, but can be removed once we
11# assume 2.62 everywhere.
12
13# Note: If the type 'long long int' exists but is only 32 bits large
14# (as on some very old compilers), HAVE_LONG_LONG_INT will not be
15# defined. In this case you can treat 'long long int' like 'long int'.
16
17AC_DEFUN([AC_TYPE_LONG_LONG_INT],
18[
19  AC_CACHE_CHECK([for long long int], [ac_cv_type_long_long_int],
20    [AC_LINK_IFELSE(
21       [_AC_TYPE_LONG_LONG_SNIPPET],
22       [dnl This catches a bug in Tandem NonStop Kernel (OSS) cc -O circa 2004.
23  dnl If cross compiling, assume the bug isn't important, since
24  dnl nobody cross compiles for this platform as far as we know.
25  AC_RUN_IFELSE(
26    [AC_LANG_PROGRAM(
27       [[@%:@include <limits.h>
28         @%:@ifndef LLONG_MAX
29         @%:@ define HALF \
30      (1LL << (sizeof (long long int) * CHAR_BIT - 2))
31         @%:@ define LLONG_MAX (HALF - 1 + HALF)
32         @%:@endif]],
33       [[long long int n = 1;
34         int i;
35         for (i = 0; ; i++)
36     {
37       long long int m = n << i;
38       if (m >> i != n)
39         return 1;
40       if (LLONG_MAX / 2 < m)
41         break;
42     }
43         return 0;]])],
44    [ac_cv_type_long_long_int=yes],
45    [ac_cv_type_long_long_int=no],
46    [ac_cv_type_long_long_int=yes])],
47       [ac_cv_type_long_long_int=no])])
48  if test $ac_cv_type_long_long_int = yes; then
49    AC_DEFINE([HAVE_LONG_LONG_INT], 1,
50      [Define to 1 if the system has the type `long long int'.])
51  fi
52])
53
54# Define HAVE_UNSIGNED_LONG_LONG_INT if 'unsigned long long int' works.
55# This fixes a bug in Autoconf 2.61, but can be removed once we
56# assume 2.62 everywhere.
57
58# Note: If the type 'unsigned long long int' exists but is only 32 bits
59# large (as on some very old compilers), AC_TYPE_UNSIGNED_LONG_LONG_INT
60# will not be defined. In this case you can treat 'unsigned long long int'
61# like 'unsigned long int'.
62
63AC_DEFUN([AC_TYPE_UNSIGNED_LONG_LONG_INT],
64[
65  AC_CACHE_CHECK([for unsigned long long int],
66    [ac_cv_type_unsigned_long_long_int],
67    [AC_LINK_IFELSE(
68       [_AC_TYPE_LONG_LONG_SNIPPET],
69       [ac_cv_type_unsigned_long_long_int=yes],
70       [ac_cv_type_unsigned_long_long_int=no])])
71  if test $ac_cv_type_unsigned_long_long_int = yes; then
72    AC_DEFINE([HAVE_UNSIGNED_LONG_LONG_INT], 1,
73      [Define to 1 if the system has the type `unsigned long long int'.])
74  fi
75])
76
77# Expands to a C program that can be used to test for simultaneous support
78# of 'long long' and 'unsigned long long'. We don't want to say that
79# 'long long' is available if 'unsigned long long' is not, or vice versa,
80# because too many programs rely on the symmetry between signed and unsigned
81# integer types (excluding 'bool').
82AC_DEFUN([_AC_TYPE_LONG_LONG_SNIPPET],
83[
84  AC_LANG_PROGRAM(
85    [[/* Test preprocessor.  */
86      #if ! (-9223372036854775807LL < 0 && 0 < 9223372036854775807ll)
87        error in preprocessor;
88      #endif
89      #if ! (18446744073709551615ULL <= -1ull)
90        error in preprocessor;
91      #endif
92      /* Test literals.  */
93      long long int ll = 9223372036854775807ll;
94      long long int nll = -9223372036854775807LL;
95      unsigned long long int ull = 18446744073709551615ULL;
96      /* Test constant expressions.   */
97      typedef int a[((-9223372036854775807LL < 0 && 0 < 9223372036854775807ll)
98         ? 1 : -1)];
99      typedef int b[(18446744073709551615ULL <= (unsigned long long int) -1
100         ? 1 : -1)];
101      int i = 63;]],
102    [[/* Test availability of runtime routines for shift and division.  */
103      long long int llmax = 9223372036854775807ll;
104      unsigned long long int ullmax = 18446744073709551615ull;
105      return ((ll << 63) | (ll >> 63) | (ll < i) | (ll > i)
106        | (llmax / ll) | (llmax % ll)
107        | (ull << 63) | (ull >> 63) | (ull << i) | (ull >> i)
108        | (ullmax / ull) | (ullmax % ull));]])
109])
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