← Back
Editing: longlong.m4
# longlong.m4 serial 17 dnl Copyright (C) 1999-2007, 2009-2016 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. # Define HAVE_LONG_LONG_INT if 'long long int' works. # This fixes a bug in Autoconf 2.61, and 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 $ac_cv_type_long_long_int = yes; then AC_DEFINE([HAVE_LONG_LONG_INT], [1], [Define to 1 if the system has the type 'long long int'.]) fi ]) # Define HAVE_UNSIGNED_LONG_LONG_INT if 'unsigned long long int' works. # This fixes a bug in Autoconf 2.61, and can be faster # than what's in Autoconf 2.62 through 2.68. # Note: If the type 'unsigned long long int' exists but is only 32 bits # large (as on some very old compilers), AC_TYPE_UNSIGNED_LONG_LONG_INT # will not be defined. In this case you can treat 'unsigned long long int' # like 'unsigned long int'. AC_DEFUN([AC_TYPE_UNSIGNED_LONG_LONG_INT], [ AC_CACHE_CHECK([for unsigned long long int], [ac_cv_type_unsigned_long_long_int], [ac_cv_type_unsigned_long_long_int=yes if test "x${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));]]) ])
Save File
Cancel