Commit | Line | Data |
---|---|---|
770d76d7 | 1 | # longlong.m4 serial 17 |
49e4877c | 2 | dnl Copyright (C) 1999-2007, 2009-2016 Free Software Foundation, Inc. |
f6ea5628 DJ |
3 | dnl This file is free software; the Free Software Foundation |
4 | dnl gives unlimited permission to copy and/or distribute it, | |
5 | dnl with or without modifications, as long as this notice is preserved. | |
6 | ||
7 | dnl From Paul Eggert. | |
8 | ||
9 | # Define HAVE_LONG_LONG_INT if 'long long int' works. | |
770d76d7 PA |
10 | # This fixes a bug in Autoconf 2.61, and can be faster |
11 | # than what's in Autoconf 2.62 through 2.68. | |
f6ea5628 DJ |
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 | ||
17 | AC_DEFUN([AC_TYPE_LONG_LONG_INT], | |
18 | [ | |
770d76d7 | 19 | AC_REQUIRE([AC_TYPE_UNSIGNED_LONG_LONG_INT]) |
f6ea5628 | 20 | AC_CACHE_CHECK([for long long int], [ac_cv_type_long_long_int], |
770d76d7 PA |
21 | [ac_cv_type_long_long_int=yes |
22 | if test "x${ac_cv_prog_cc_c99-no}" = xno; then | |
23 | ac_cv_type_long_long_int=$ac_cv_type_unsigned_long_long_int | |
24 | if test $ac_cv_type_long_long_int = yes; then | |
25 | dnl Catch a bug in Tandem NonStop Kernel (OSS) cc -O circa 2004. | |
26 | dnl If cross compiling, assume the bug is not important, since | |
27 | dnl nobody cross compiles for this platform as far as we know. | |
28 | AC_RUN_IFELSE( | |
29 | [AC_LANG_PROGRAM( | |
30 | [[@%:@include <limits.h> | |
31 | @%:@ifndef LLONG_MAX | |
32 | @%:@ define HALF \ | |
33 | (1LL << (sizeof (long long int) * CHAR_BIT - 2)) | |
34 | @%:@ define LLONG_MAX (HALF - 1 + HALF) | |
35 | @%:@endif]], | |
36 | [[long long int n = 1; | |
37 | int i; | |
38 | for (i = 0; ; i++) | |
39 | { | |
40 | long long int m = n << i; | |
41 | if (m >> i != n) | |
42 | return 1; | |
43 | if (LLONG_MAX / 2 < m) | |
44 | break; | |
45 | } | |
46 | return 0;]])], | |
47 | [], | |
48 | [ac_cv_type_long_long_int=no], | |
49 | [:]) | |
50 | fi | |
51 | fi]) | |
f6ea5628 | 52 | if test $ac_cv_type_long_long_int = yes; then |
f434ba03 | 53 | AC_DEFINE([HAVE_LONG_LONG_INT], [1], |
770d76d7 | 54 | [Define to 1 if the system has the type 'long long int'.]) |
f6ea5628 DJ |
55 | fi |
56 | ]) | |
57 | ||
58 | # Define HAVE_UNSIGNED_LONG_LONG_INT if 'unsigned long long int' works. | |
770d76d7 PA |
59 | # This fixes a bug in Autoconf 2.61, and can be faster |
60 | # than what's in Autoconf 2.62 through 2.68. | |
f6ea5628 DJ |
61 | |
62 | # Note: If the type 'unsigned long long int' exists but is only 32 bits | |
63 | # large (as on some very old compilers), AC_TYPE_UNSIGNED_LONG_LONG_INT | |
64 | # will not be defined. In this case you can treat 'unsigned long long int' | |
65 | # like 'unsigned long int'. | |
66 | ||
67 | AC_DEFUN([AC_TYPE_UNSIGNED_LONG_LONG_INT], | |
68 | [ | |
69 | AC_CACHE_CHECK([for unsigned long long int], | |
70 | [ac_cv_type_unsigned_long_long_int], | |
770d76d7 PA |
71 | [ac_cv_type_unsigned_long_long_int=yes |
72 | if test "x${ac_cv_prog_cc_c99-no}" = xno; then | |
73 | AC_LINK_IFELSE( | |
74 | [_AC_TYPE_LONG_LONG_SNIPPET], | |
75 | [], | |
76 | [ac_cv_type_unsigned_long_long_int=no]) | |
77 | fi]) | |
f6ea5628 | 78 | if test $ac_cv_type_unsigned_long_long_int = yes; then |
f434ba03 | 79 | AC_DEFINE([HAVE_UNSIGNED_LONG_LONG_INT], [1], |
770d76d7 | 80 | [Define to 1 if the system has the type 'unsigned long long int'.]) |
f6ea5628 DJ |
81 | fi |
82 | ]) | |
83 | ||
84 | # Expands to a C program that can be used to test for simultaneous support | |
85 | # of 'long long' and 'unsigned long long'. We don't want to say that | |
86 | # 'long long' is available if 'unsigned long long' is not, or vice versa, | |
87 | # because too many programs rely on the symmetry between signed and unsigned | |
88 | # integer types (excluding 'bool'). | |
89 | AC_DEFUN([_AC_TYPE_LONG_LONG_SNIPPET], | |
90 | [ | |
91 | AC_LANG_PROGRAM( | |
92 | [[/* For now, do not test the preprocessor; as of 2007 there are too many | |
f434ba03 PA |
93 | implementations with broken preprocessors. Perhaps this can |
94 | be revisited in 2012. In the meantime, code should not expect | |
95 | #if to work with literals wider than 32 bits. */ | |
f6ea5628 DJ |
96 | /* Test literals. */ |
97 | long long int ll = 9223372036854775807ll; | |
98 | long long int nll = -9223372036854775807LL; | |
99 | unsigned long long int ull = 18446744073709551615ULL; | |
100 | /* Test constant expressions. */ | |
101 | typedef int a[((-9223372036854775807LL < 0 && 0 < 9223372036854775807ll) | |
f434ba03 | 102 | ? 1 : -1)]; |
f6ea5628 | 103 | typedef int b[(18446744073709551615ULL <= (unsigned long long int) -1 |
f434ba03 | 104 | ? 1 : -1)]; |
f6ea5628 DJ |
105 | int i = 63;]], |
106 | [[/* Test availability of runtime routines for shift and division. */ | |
107 | long long int llmax = 9223372036854775807ll; | |
108 | unsigned long long int ullmax = 18446744073709551615ull; | |
109 | return ((ll << 63) | (ll >> 63) | (ll < i) | (ll > i) | |
f434ba03 PA |
110 | | (llmax / ll) | (llmax % ll) |
111 | | (ull << 63) | (ull >> 63) | (ull << i) | (ull >> i) | |
112 | | (ullmax / ull) | (ullmax % ull));]]) | |
f6ea5628 | 113 | ]) |