std_limits.h

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// The template and inlines for the -*- C++ -*- numeric_limits classes.

// Copyright (C) 1999, 2000, 2001, 2002 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library.  This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 2, or (at your option)
// any later version.

// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License along
// with this library; see the file COPYING.  If not, write to the Free
// Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
// USA.

// As a special exception, you may use this file as part of a free software
// library without restriction.  Specifically, if other files instantiate
// templates or use macros or inline functions from this file, or you compile
// this file and link it with other files to produce an executable, this
// file does not by itself cause the resulting executable to be covered by
// the GNU General Public License.  This exception does not however
// invalidate any other reasons why the executable file might be covered by
// the GNU General Public License.

// Note: this is not a conforming implementation.
// Written by Gabriel Dos Reis <[e-mail]>

//
// ISO 14882:1998
// 18.2.1
//

/** @file limits
 *  This is a Standard C++ Library header.  You should @c #include this header
 *  in your programs, rather than any of the "st[dl]_*.h" implementation files.
 */

#ifndef _CPP_NUMERIC_LIMITS
#define _CPP_NUMERIC_LIMITS 1

#pragma GCC system_header

#include <bits/cpu_limits.h>
#include <bits/c++config.h>

//
// The numeric_limits<> traits document implementation-defined aspects
// of fundamental arithmetic data types (integers and floating points).
// From Standard C++ point of view, there are 13 such types:
//   * integers
//         bool						        (1)
//         char, signed char, unsigned char			(3)
//         short, unsigned short				(2)
//         int, unsigned					(2)
//         long, unsigned long					(2)
//
//   * floating points
//         float						(1)
//         double						(1)
//         long double						(1)
//
// GNU C++ undertstands (where supported by the host C-library) 
//   * integer
//         long long, unsigned long long			(2)
//
// which brings us to 15 fundamental arithmetic data types in GNU C++.
//
// 
// Since a numeric_limits<> is a bit tricky to get right, we rely on
// an interface composed of macros which should be defined in config/os
// or config/cpu when they differ from the generic (read arbitrary)
// definitions given here.
//

// These values can be overridden in the target configuration file.
// The default values are appropriate for many 32-bit targets.

#ifndef __glibcpp_char_bits
#define __glibcpp_char_bits 8
#endif
#ifdef __CHAR_UNSIGNED__
#define __glibcpp_plain_char_is_signed false
#else
#define __glibcpp_plain_char_is_signed true
#endif
#ifndef __glibcpp_short_bits
#define __glibcpp_short_bits 16
#endif
#ifndef __glibcpp_int_bits
#define __glibcpp_int_bits 32
#endif
#ifndef __glibcpp_long_bits
#define __glibcpp_long_bits 32
#endif
#ifndef __glibcpp_wchar_t_bits
#define __glibcpp_wchar_t_bits 32
#endif
#ifndef __glibcpp_wchar_t_is_signed
#define __glibcpp_wchar_t_is_signed true
#endif
#ifndef __glibcpp_long_long_bits
#define __glibcpp_long_long_bits 64
#endif
#ifndef __glibcpp_float_bits
#define __glibcpp_float_bits 32
#endif
#ifndef __glibcpp_double_bits
#define __glibcpp_double_bits 64
#endif
#ifndef __glibcpp_long_double_bits
#define __glibcpp_long_double_bits 128
#endif

#ifndef __glibcpp_char_traps
#define __glibcpp_char_traps true
#endif
#ifndef __glibcpp_short_traps
#define __glibcpp_short_traps true
#endif
#ifndef __glibcpp_int_traps
#define __glibcpp_int_traps true
#endif
#ifndef __glibcpp_long_traps
#define __glibcpp_long_traps true
#endif
#ifndef __glibcpp_wchar_t_traps
#define __glibcpp_wchar_t_traps true
#endif
#ifndef __glibcpp_long_long_traps
#define __glibcpp_long_long_traps true
#endif

// You should not need to define any macros below this point, unless
// you have a machine with non-standard bit-widths.

// These values are the minimums and maximums for standard data types
// of common widths.

#define __glibcpp_s8_max 127
#define __glibcpp_s8_min (-__glibcpp_s8_max - 1)
#define __glibcpp_s8_digits 7
#define __glibcpp_s8_digits10 2
#define __glibcpp_u8_min 0U
#define __glibcpp_u8_max (__glibcpp_s8_max * 2 + 1)
#define __glibcpp_u8_digits 8
#define __glibcpp_u8_digits10 2
#define __glibcpp_s16_max 32767
#define __glibcpp_s16_min (-__glibcpp_s16_max - 1)
#define __glibcpp_s16_digits 15
#define __glibcpp_s16_digits10 4
#define __glibcpp_u16_min 0U
#define __glibcpp_u16_max (__glibcpp_s16_max * 2 + 1)
#define __glibcpp_u16_digits 16
#define __glibcpp_u16_digits10 4
#define __glibcpp_s32_max 2147483647L
#define __glibcpp_s32_min (-__glibcpp_s32_max - 1)
#define __glibcpp_s32_digits 31
#define __glibcpp_s32_digits10 9
#define __glibcpp_u32_min 0UL
#define __glibcpp_u32_max (__glibcpp_s32_max * 2U + 1)
#define __glibcpp_u32_digits 32
#define __glibcpp_u32_digits10 9
#define __glibcpp_s64_max 9223372036854775807LL
#define __glibcpp_s64_min (-__glibcpp_s64_max - 1)
#define __glibcpp_s64_digits 63
#define __glibcpp_s64_digits10 18
#define __glibcpp_u64_min 0ULL
#define __glibcpp_u64_max (__glibcpp_s64_max * 2ULL + 1)
#define __glibcpp_u64_digits 64
#define __glibcpp_u64_digits10 19

#define __glibcpp_f32_min 1.17549435e-38F
#define __glibcpp_f32_max 3.40282347e+38F
#define __glibcpp_f32_digits 24
#define __glibcpp_f32_digits10 6
#define __glibcpp_f32_radix 2
#define __glibcpp_f32_epsilon 1.19209290e-07F
#define __glibcpp_f32_round_error 1.0F
#define __glibcpp_f32_min_exponent -125
#define __glibcpp_f32_min_exponent10 -37
#define __glibcpp_f32_max_exponent 128
#define __glibcpp_f32_max_exponent10 38
#define __glibcpp_f64_min 2.2250738585072014e-308
#define __glibcpp_f64_max 1.7976931348623157e+308
#define __glibcpp_f64_digits 53
#define __glibcpp_f64_digits10 15
#define __glibcpp_f64_radix 2
#define __glibcpp_f64_epsilon 2.2204460492503131e-16
#define __glibcpp_f64_round_error 1.0
#define __glibcpp_f64_min_exponent -1021
#define __glibcpp_f64_min_exponent10 -307
#define __glibcpp_f64_max_exponent 1024
#define __glibcpp_f64_max_exponent10 308
#define __glibcpp_f80_min 3.36210314311209350626e-4932L
#define __glibcpp_f80_max 1.18973149535723176502e+4932L
#define __glibcpp_f80_digits 64
#define __glibcpp_f80_digits10 18
#define __glibcpp_f80_radix 2
#define __glibcpp_f80_epsilon 1.08420217248550443401e-19L
#define __glibcpp_f80_round_error 1.0L
#define __glibcpp_f80_min_exponent -16381
#define __glibcpp_f80_min_exponent10 -4931
#define __glibcpp_f80_max_exponent 16384
#define __glibcpp_f80_max_exponent10 4932
#define __glibcpp_f96_min 1.68105157155604675313e-4932L
#define __glibcpp_f96_max 1.18973149535723176502e+4932L
#define __glibcpp_f96_digits 64
#define __glibcpp_f96_digits10 18
#define __glibcpp_f96_radix 2
#define __glibcpp_f96_epsilon 1.08420217248550443401e-19L
#define __glibcpp_f96_round_error 1.0L
#define __glibcpp_f96_min_exponent -16382
#define __glibcpp_f96_min_exponent10 -4931
#define __glibcpp_f96_max_exponent 16384
#define __glibcpp_f96_max_exponent10 4932
#define __glibcpp_f128_min 3.362103143112093506262677817321752603E-4932L
#define __glibcpp_f128_max 1.189731495357231765085759326628007016E+4932L
#define __glibcpp_f128_digits 113
#define __glibcpp_f128_digits10 33
#define __glibcpp_f128_radix 2
#define __glibcpp_f128_epsilon 1.925929944387235853055977942584927319E-34L
#define __glibcpp_f128_round_error 1.0L
#define __glibcpp_f128_min_exponent -16381
#define __glibcpp_f128_min_exponent10 -4931
#define __glibcpp_f128_max_exponent 16384
#define __glibcpp_f128_max_exponent10 4932

// bool-specific hooks:
//     __glibcpp_bool_digits  __glibcpp_int_traps __glibcpp_long_traps

#ifndef __glibcpp_bool_digits
#define __glibcpp_bool_digits 1
#endif

// char.

#define __glibcpp_plain_char_traps true
#define __glibcpp_signed_char_traps true
#define __glibcpp_unsigned_char_traps true
#ifndef __glibcpp_char_is_modulo
#define __glibcpp_char_is_modulo true
#endif
#ifndef __glibcpp_signed_char_is_modulo
#define __glibcpp_signed_char_is_modulo true
#endif
#if __glibcpp_char_bits == 8
#define __glibcpp_signed_char_min __glibcpp_s8_min
#define __glibcpp_signed_char_max __glibcpp_s8_max
#define __glibcpp_signed_char_digits __glibcpp_s8_digits
#define __glibcpp_signed_char_digits10 __glibcpp_s8_digits10
#define __glibcpp_unsigned_char_min __glibcpp_u8_min
#define __glibcpp_unsigned_char_max __glibcpp_u8_max
#define __glibcpp_unsigned_char_digits __glibcpp_u8_digits
#define __glibcpp_unsigned_char_digits10 __glibcpp_u8_digits10
#elif __glibcpp_char_bits == 16
#define __glibcpp_signed_char_min __glibcpp_s16_min
#define __glibcpp_signed_char_max __glibcpp_s16_max
#define __glibcpp_signed_char_digits __glibcpp_s16_digits
#define __glibcpp_signed_char_digits10 __glibcpp_s16_digits10
#define __glibcpp_unsigned_char_min __glibcpp_u16_min
#define __glibcpp_unsigned_char_max __glibcpp_u16_max
#define __glibcpp_unsigned_char_digits __glibcpp_u16_digits
#define __glibcpp_unsigned_char_digits10 __glibcpp_u16_digits10
#elif __glibcpp_char_bits == 32
#define __glibcpp_signed_char_min (signed char)__glibcpp_s32_min
#define __glibcpp_signed_char_max (signed char)__glibcpp_s32_max
#define __glibcpp_signed_char_digits __glibcpp_s32_digits
#define __glibcpp_signed_char_digits10 __glibcpp_s32_digits10
#define __glibcpp_unsigned_char_min (unsigned char)__glibcpp_u32_min
#define __glibcpp_unsigned_char_max (unsigned char)__glibcpp_u32_max
#define __glibcpp_unsigned_char_digits __glibcpp_u32_digits
#define __glibcpp_unsigned_char_digits10 __glibcpp_u32_digits10
#elif __glibcpp_char_bits == 64
#define __glibcpp_signed_char_min (signed char)__glibcpp_s64_min
#define __glibcpp_signed_char_max (signed char)__glibcpp_s64_max
#define __glibcpp_signed_char_digits __glibcpp_s64_digits
#define __glibcpp_signed_char_digits10 __glibcpp_s64_digits10
#define __glibcpp_unsigned_char_min (unsigned char)__glibcpp_u64_min
#define __glibcpp_unsigned_char_max (unsigned char)__glibcpp_u64_max
#define __glibcpp_unsigned_char_digits __glibcpp_u64_digits
#define __glibcpp_unsigned_char_digits10 __glibcpp_u64_digits10
#else
// You must define these macros in the configuration file.
#endif

#if __glibcpp_plain_char_is_signed
#define __glibcpp_char_min (char)__glibcpp_signed_char_min
#define __glibcpp_char_max (char)__glibcpp_signed_char_max
#define __glibcpp_char_digits __glibcpp_signed_char_digits
#define __glibcpp_char_digits10 __glibcpp_signed_char_digits10
#else
#define __glibcpp_char_min (char)__glibcpp_unsigned_char_min
#define __glibcpp_char_max (char)__glibcpp_unsigned_char_max
#define __glibcpp_char_digits __glibcpp_unsigned_char_digits
#define __glibcpp_char_digits10 __glibcpp_unsigned_char_digits10
#endif

// short

#define __glibcpp_signed_short_traps true
#define __glibcpp_unsigned_short_traps true
#ifndef __glibcpp_signed_short_is_modulo
#define __glibcpp_signed_short_is_modulo true
#endif
#if __glibcpp_short_bits == 8
#define __glibcpp_signed_short_min __glibcpp_s8_min
#define __glibcpp_signed_short_max __glibcpp_s8_max
#define __glibcpp_signed_short_digits __glibcpp_s8_digits
#define __glibcpp_signed_short_digits10 __glibcpp_s8_digits10
#define __glibcpp_unsigned_short_min __glibcpp_u8_min
#define __glibcpp_unsigned_short_max __glibcpp_u8_max
#define __glibcpp_unsigned_short_digits __glibcpp_u8_digits
#define __glibcpp_unsigned_short_digits10 __glibcpp_u8_digits10
#elif __glibcpp_short_bits == 16
#define __glibcpp_signed_short_min __glibcpp_s16_min
#define __glibcpp_signed_short_max __glibcpp_s16_max
#define __glibcpp_signed_short_digits __glibcpp_s16_digits
#define __glibcpp_signed_short_digits10 __glibcpp_s16_digits10
#define __glibcpp_unsigned_short_min __glibcpp_u16_min
#define __glibcpp_unsigned_short_max __glibcpp_u16_max
#define __glibcpp_unsigned_short_digits __glibcpp_u16_digits
#define __glibcpp_unsigned_short_digits10 __glibcpp_u16_digits10
#elif __glibcpp_short_bits == 32
#define __glibcpp_signed_short_min (short)__glibcpp_s32_min
#define __glibcpp_signed_short_max (short)__glibcpp_s32_max
#define __glibcpp_signed_short_digits __glibcpp_s32_digits
#define __glibcpp_signed_short_digits10 __glibcpp_s32_digits10
#define __glibcpp_unsigned_short_min (unsigned short)__glibcpp_u32_min
#define __glibcpp_unsigned_short_max (unsigned short)__glibcpp_u32_max
#define __glibcpp_unsigned_short_digits __glibcpp_u32_digits
#define __glibcpp_unsigned_short_digits10 __glibcpp_u32_digits10
#elif __glibcpp_short_bits == 64
#define __glibcpp_signed_short_min (short)__glibcpp_s64_min
#define __glibcpp_signed_short_max (short)__glibcpp_s64_max
#define __glibcpp_signed_short_digits __glibcpp_s64_digits
#define __glibcpp_signed_short_digits10 __glibcpp_s64_digits10
#define __glibcpp_unsigned_short_min (unsigned short)__glibcpp_u64_min
#define __glibcpp_unsigned_short_max (unsigned short)__glibcpp_u64_max
#define __glibcpp_unsigned_short_digits __glibcpp_u64_digits
#define __glibcpp_unsigned_short_digits10 __glibcpp_u64_digits10
#else
// You must define these macros in the configuration file.
#endif

// int

#define __glibcpp_signed_int_traps true