1 # longlong.m4 serial 14
2 dnl Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
3 dnl 2009, 2010 Free Software Foundation, Inc.
4 dnl This file is free software; the Free Software Foundation
5 dnl gives unlimited permission to copy and/or distribute it,
6 dnl with or without modifications, as long as this notice is preserved.
10 # Define HAVE_LONG_LONG_INT if 'long long int' works.
11 # This fixes a bug in Autoconf 2.61, but can be removed once we
12 # assume 2.62 everywhere.
14 # Note: If the type 'long long int' exists but is only 32 bits large
15 # (as on some very old compilers), HAVE_LONG_LONG_INT will not be
16 # defined. In this case you can treat 'long long int' like 'long int'.
18 AC_DEFUN([AC_TYPE_LONG_LONG_INT],
20 AC_CACHE_CHECK([for long long int], [ac_cv_type_long_long_int],
22 [_AC_TYPE_LONG_LONG_SNIPPET],
23 [dnl This catches a bug in Tandem NonStop Kernel (OSS) cc -O circa 2004.
24 dnl If cross compiling, assume the bug isn't important, since
25 dnl nobody cross compiles for this platform as far as we know.
28 [[@%:@include <limits.h>
31 (1LL << (sizeof (long long int) * CHAR_BIT - 2))
32 @%:@ define LLONG_MAX (HALF - 1 + HALF)
34 [[long long int n = 1;
38 long long int m = n << i;
41 if (LLONG_MAX / 2 < m)
45 [ac_cv_type_long_long_int=yes],
46 [ac_cv_type_long_long_int=no],
47 [ac_cv_type_long_long_int=yes])],
48 [ac_cv_type_long_long_int=no])])
49 if test $ac_cv_type_long_long_int = yes; then
50 AC_DEFINE([HAVE_LONG_LONG_INT], [1],
51 [Define to 1 if the system has the type `long long int'.])
55 # Define HAVE_UNSIGNED_LONG_LONG_INT if 'unsigned long long int' works.
56 # This fixes a bug in Autoconf 2.61, but can be removed once we
57 # assume 2.62 everywhere.
59 # Note: If the type 'unsigned long long int' exists but is only 32 bits
60 # large (as on some very old compilers), AC_TYPE_UNSIGNED_LONG_LONG_INT
61 # will not be defined. In this case you can treat 'unsigned long long int'
62 # like 'unsigned long int'.
64 AC_DEFUN([AC_TYPE_UNSIGNED_LONG_LONG_INT],
66 AC_CACHE_CHECK([for unsigned long long int],
67 [ac_cv_type_unsigned_long_long_int],
69 [_AC_TYPE_LONG_LONG_SNIPPET],
70 [ac_cv_type_unsigned_long_long_int=yes],
71 [ac_cv_type_unsigned_long_long_int=no])])
72 if test $ac_cv_type_unsigned_long_long_int = yes; then
73 AC_DEFINE([HAVE_UNSIGNED_LONG_LONG_INT], [1],
74 [Define to 1 if the system has the type `unsigned long long int'.])
78 # Expands to a C program that can be used to test for simultaneous support
79 # of 'long long' and 'unsigned long long'. We don't want to say that
80 # 'long long' is available if 'unsigned long long' is not, or vice versa,
81 # because too many programs rely on the symmetry between signed and unsigned
82 # integer types (excluding 'bool').
83 AC_DEFUN([_AC_TYPE_LONG_LONG_SNIPPET],
86 [[/* For now, do not test the preprocessor; as of 2007 there are too many
87 implementations with broken preprocessors. Perhaps this can
88 be revisited in 2012. In the meantime, code should not expect
89 #if to work with literals wider than 32 bits. */
91 long long int ll = 9223372036854775807ll;
92 long long int nll = -9223372036854775807LL;
93 unsigned long long int ull = 18446744073709551615ULL;
94 /* Test constant expressions. */
95 typedef int a[((-9223372036854775807LL < 0 && 0 < 9223372036854775807ll)
97 typedef int b[(18446744073709551615ULL <= (unsigned long long int) -1
100 [[/* Test availability of runtime routines for shift and division. */
101 long long int llmax = 9223372036854775807ll;
102 unsigned long long int ullmax = 18446744073709551615ull;
103 return ((ll << 63) | (ll >> 63) | (ll < i) | (ll > i)
104 | (llmax / ll) | (llmax % ll)
105 | (ull << 63) | (ull >> 63) | (ull << i) | (ull >> i)
106 | (ullmax / ull) | (ullmax % ull));]])