You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
84 lines
4.1 KiB
HTML
84 lines
4.1 KiB
HTML
<html lang="en">
|
|
<head>
|
|
<title>Long Long - Using the GNU Compiler Collection (GCC)</title>
|
|
<meta http-equiv="Content-Type" content="text/html">
|
|
<meta name="description" content="Using the GNU Compiler Collection (GCC)">
|
|
<meta name="generator" content="makeinfo 4.13">
|
|
<link title="Top" rel="start" href="index.html#Top">
|
|
<link rel="up" href="C-Extensions.html#C-Extensions" title="C Extensions">
|
|
<link rel="prev" href="_005f_005fint128.html#g_t_005f_005fint128" title="__int128">
|
|
<link rel="next" href="Complex.html#Complex" title="Complex">
|
|
<link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage">
|
|
<!--
|
|
Copyright (C) 1988-2015 Free Software Foundation, Inc.
|
|
|
|
Permission is granted to copy, distribute and/or modify this document
|
|
under the terms of the GNU Free Documentation License, Version 1.3 or
|
|
any later version published by the Free Software Foundation; with the
|
|
Invariant Sections being ``Funding Free Software'', the Front-Cover
|
|
Texts being (a) (see below), and with the Back-Cover Texts being (b)
|
|
(see below). A copy of the license is included in the section entitled
|
|
``GNU Free Documentation License''.
|
|
|
|
(a) The FSF's Front-Cover Text is:
|
|
|
|
A GNU Manual
|
|
|
|
(b) The FSF's Back-Cover Text is:
|
|
|
|
You have freedom to copy and modify this GNU Manual, like GNU
|
|
software. Copies published by the Free Software Foundation raise
|
|
funds for GNU development.-->
|
|
<meta http-equiv="Content-Style-Type" content="text/css">
|
|
<style type="text/css"><!--
|
|
pre.display { font-family:inherit }
|
|
pre.format { font-family:inherit }
|
|
pre.smalldisplay { font-family:inherit; font-size:smaller }
|
|
pre.smallformat { font-family:inherit; font-size:smaller }
|
|
pre.smallexample { font-size:smaller }
|
|
pre.smalllisp { font-size:smaller }
|
|
span.sc { font-variant:small-caps }
|
|
span.roman { font-family:serif; font-weight:normal; }
|
|
span.sansserif { font-family:sans-serif; font-weight:normal; }
|
|
--></style>
|
|
</head>
|
|
<body>
|
|
<div class="node">
|
|
<a name="Long-Long"></a>
|
|
<p>
|
|
Next: <a rel="next" accesskey="n" href="Complex.html#Complex">Complex</a>,
|
|
Previous: <a rel="previous" accesskey="p" href="_005f_005fint128.html#g_t_005f_005fint128">__int128</a>,
|
|
Up: <a rel="up" accesskey="u" href="C-Extensions.html#C-Extensions">C Extensions</a>
|
|
<hr>
|
|
</div>
|
|
|
|
<h3 class="section">6.9 Double-Word Integers</h3>
|
|
|
|
<p><a name="index-g_t_0040code_007blong-long_007d-data-types-2905"></a><a name="index-double_002dword-arithmetic-2906"></a><a name="index-multiprecision-arithmetic-2907"></a><a name="index-g_t_0040code_007bLL_007d-integer-suffix-2908"></a><a name="index-g_t_0040code_007bULL_007d-integer-suffix-2909"></a>
|
|
ISO C99 supports data types for integers that are at least 64 bits wide,
|
|
and as an extension GCC supports them in C90 mode and in C++.
|
|
Simply write <code>long long int</code> for a signed integer, or
|
|
<code>unsigned long long int</code> for an unsigned integer. To make an
|
|
integer constant of type <code>long long int</code>, add the suffix ‘<samp><span class="samp">LL</span></samp>’
|
|
to the integer. To make an integer constant of type <code>unsigned long
|
|
long int</code>, add the suffix ‘<samp><span class="samp">ULL</span></samp>’ to the integer.
|
|
|
|
<p>You can use these types in arithmetic like any other integer types.
|
|
Addition, subtraction, and bitwise boolean operations on these types
|
|
are open-coded on all types of machines. Multiplication is open-coded
|
|
if the machine supports a fullword-to-doubleword widening multiply
|
|
instruction. Division and shifts are open-coded only on machines that
|
|
provide special support. The operations that are not open-coded use
|
|
special library routines that come with GCC.
|
|
|
|
<p>There may be pitfalls when you use <code>long long</code> types for function
|
|
arguments without function prototypes. If a function
|
|
expects type <code>int</code> for its argument, and you pass a value of type
|
|
<code>long long int</code>, confusion results because the caller and the
|
|
subroutine disagree about the number of bytes for the argument.
|
|
Likewise, if the function expects <code>long long int</code> and you pass
|
|
<code>int</code>. The best way to avoid such problems is to use prototypes.
|
|
|
|
</body></html>
|
|
|