1 # longlong.m4 serial 17 2 dnl Copyright (C) 1999-2007, 2009-2012 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, and can be faster 11 # than what's in Autoconf 2.62 through 2.68. 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_REQUIRE([AC_TYPE_UNSIGNED_LONG_LONG_INT]) 20 AC_CACHE_CHECK([for long long int], [ac_cv_type_long_long_int], 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]) 52 if test $ac_cv_type_long_long_int = yes; then 53 AC_DEFINE([HAVE_LONG_LONG_INT], [1], 54 [Define to 1 if the system has the type 'long long int'.]) 55 fi 56 ]) 57 58 # Define HAVE_UNSIGNED_LONG_LONG_INT if 'unsigned long long int' works. 59 # This fixes a bug in Autoconf 2.61, and can be faster 60 # than what's in Autoconf 2.62 through 2.68. 61 62 # Note: If the type 'unsigned long long int' exists but is only 32 bits 63 # large (as on some very old compilers), AC_TYPE_UNSIGNED_LONG_LONG_INT 64 # will not be defined. In this case you can treat 'unsigned long long int' 65 # like 'unsigned long int'. 66 67 AC_DEFUN([AC_TYPE_UNSIGNED_LONG_LONG_INT], 68 [ 69 AC_CACHE_CHECK([for unsigned long long int], 70 [ac_cv_type_unsigned_long_long_int], 71 [ac_cv_type_unsigned_long_long_int=yes 72 if test "x${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]) 78 if test $ac_cv_type_unsigned_long_long_int = yes; then 79 AC_DEFINE([HAVE_UNSIGNED_LONG_LONG_INT], [1], 80 [Define to 1 if the system has the type 'unsigned long long int'.]) 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 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. */ 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) 102 ? 1 : -1)]; 103 typedef int b[(18446744073709551615ULL <= (unsigned long long int) -1 104 ? 1 : -1)]; 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) 110 | (llmax / ll) | (llmax % ll) 111 | (ull << 63) | (ull >> 63) | (ull << i) | (ull >> i) 112 | (ullmax / ull) | (ullmax % ull));]]) 113 ]) 114
