| # longlong.m4 serial 18 |
| dnl Copyright (C) 1999-2007, 2009-2019 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. |
| |
| dnl From Paul Eggert. |
| |
| AC_PREREQ([2.62]) |
| |
| # Define HAVE_LONG_LONG_INT if 'long long int' works. |
| # This can be faster than what's in Autoconf 2.62 through 2.68. |
| |
| # Note: If the type 'long long int' exists but is only 32 bits large |
| # (as on some very old compilers), HAVE_LONG_LONG_INT will not be |
| # defined. In this case you can treat 'long long int' like 'long int'. |
| |
| AC_DEFUN([AC_TYPE_LONG_LONG_INT], |
| [ |
| AC_REQUIRE([AC_TYPE_UNSIGNED_LONG_LONG_INT]) |
| AC_CACHE_CHECK([for long long int], [ac_cv_type_long_long_int], |
| [ac_cv_type_long_long_int=yes |
| if test "x${ac_cv_prog_cc_c99-no}" = xno; then |
| ac_cv_type_long_long_int=$ac_cv_type_unsigned_long_long_int |
| if test $ac_cv_type_long_long_int = yes; then |
| dnl Catch a bug in Tandem NonStop Kernel (OSS) cc -O circa 2004. |
| dnl If cross compiling, assume the bug is not important, since |
| dnl nobody cross compiles for this platform as far as we know. |
| AC_RUN_IFELSE( |
| [AC_LANG_PROGRAM( |
| [[@%:@include <limits.h> |
| @%:@ifndef LLONG_MAX |
| @%:@ define HALF \ |
| (1LL << (sizeof (long long int) * CHAR_BIT - 2)) |
| @%:@ define LLONG_MAX (HALF - 1 + HALF) |
| @%:@endif]], |
| [[long long int n = 1; |
| int i; |
| for (i = 0; ; i++) |
| { |
| long long int m = n << i; |
| if (m >> i != n) |
| return 1; |
| if (LLONG_MAX / 2 < m) |
| break; |
| } |
| return 0;]])], |
| [], |
| [ac_cv_type_long_long_int=no], |
| [:]) |
| fi |
| fi]) |
| if test $ac_cv_type_long_long_int = yes; then |
| AC_DEFINE([HAVE_LONG_LONG_INT], [1], |
| [Define to 1 if the system has the type 'long long int'.]) |
| fi |
| ]) |
| |
| # Define HAVE_UNSIGNED_LONG_LONG_INT if 'unsigned long long int' works. |
| # This can be faster than what's in Autoconf 2.62 through 2.68. |
| |
| # Note: If the type 'unsigned long long int' exists but is only 32 bits |
| # large (as on some very old compilers), AC_TYPE_UNSIGNED_LONG_LONG_INT |
| # will not be defined. In this case you can treat 'unsigned long long int' |
| # like 'unsigned long int'. |
| |
| AC_DEFUN([AC_TYPE_UNSIGNED_LONG_LONG_INT], |
| [ |
| AC_CACHE_CHECK([for unsigned long long int], |
| [ac_cv_type_unsigned_long_long_int], |
| [ac_cv_type_unsigned_long_long_int=yes |
| if test "x${ac_cv_prog_cc_c99-no}" = xno; then |
| AC_LINK_IFELSE( |
| [_AC_TYPE_LONG_LONG_SNIPPET], |
| [], |
| [ac_cv_type_unsigned_long_long_int=no]) |
| fi]) |
| if test $ac_cv_type_unsigned_long_long_int = yes; then |
| AC_DEFINE([HAVE_UNSIGNED_LONG_LONG_INT], [1], |
| [Define to 1 if the system has the type 'unsigned long long int'.]) |
| fi |
| ]) |
| |
| # Expands to a C program that can be used to test for simultaneous support |
| # of 'long long' and 'unsigned long long'. We don't want to say that |
| # 'long long' is available if 'unsigned long long' is not, or vice versa, |
| # because too many programs rely on the symmetry between signed and unsigned |
| # integer types (excluding 'bool'). |
| AC_DEFUN([_AC_TYPE_LONG_LONG_SNIPPET], |
| [ |
| AC_LANG_PROGRAM( |
| [[/* For now, do not test the preprocessor; as of 2007 there are too many |
| implementations with broken preprocessors. Perhaps this can |
| be revisited in 2012. In the meantime, code should not expect |
| #if to work with literals wider than 32 bits. */ |
| /* Test literals. */ |
| long long int ll = 9223372036854775807ll; |
| long long int nll = -9223372036854775807LL; |
| unsigned long long int ull = 18446744073709551615ULL; |
| /* Test constant expressions. */ |
| typedef int a[((-9223372036854775807LL < 0 && 0 < 9223372036854775807ll) |
| ? 1 : -1)]; |
| typedef int b[(18446744073709551615ULL <= (unsigned long long int) -1 |
| ? 1 : -1)]; |
| int i = 63;]], |
| [[/* Test availability of runtime routines for shift and division. */ |
| long long int llmax = 9223372036854775807ll; |
| unsigned long long int ullmax = 18446744073709551615ull; |
| return ((ll << 63) | (ll >> 63) | (ll < i) | (ll > i) |
| | (llmax / ll) | (llmax % ll) |
| | (ull << 63) | (ull >> 63) | (ull << i) | (ull >> i) |
| | (ullmax / ull) | (ullmax % ull));]]) |
| ]) |