1 # longlong.m4 serial 14 2 dnl Copyright (C) 1999-2007, 2009 Free Software Foundation, Inc. 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. 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 17 AC_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 63 AC_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'). 82 AC_DEFUN([_AC_TYPE_LONG_LONG_SNIPPET], 83 [ 84 AC_LANG_PROGRAM( 85 [[/* For now, do not test the preprocessor; as of 2007 there are too many 86 implementations with broken preprocessors. Perhaps this can 87 be revisited in 2012. In the meantime, code should not expect 88 #if to work with literals wider than 32 bits. */ 89 /* Test literals. */ 90 long long int ll = 9223372036854775807ll; 91 long long int nll = -9223372036854775807LL; 92 unsigned long long int ull = 18446744073709551615ULL; 93 /* Test constant expressions. */ 94 typedef int a[((-9223372036854775807LL < 0 && 0 < 9223372036854775807ll) 95 ? 1 : -1)]; 96 typedef int b[(18446744073709551615ULL <= (unsigned long long int) -1 97 ? 1 : -1)]; 98 int i = 63;]], 99 [[/* Test availability of runtime routines for shift and division. */ 100 long long int llmax = 9223372036854775807ll; 101 unsigned long long int ullmax = 18446744073709551615ull; 102 return ((ll << 63) | (ll >> 63) | (ll < i) | (ll > i) 103 | (llmax / ll) | (llmax % ll) 104 | (ull << 63) | (ull >> 63) | (ull << i) | (ull >> i) 105 | (ullmax / ull) | (ullmax % ull));]]) 106 ]) 107
