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diff --git a/share/doc/gfortran/AUTOMATIC-and-STATIC-attributes.html b/share/doc/gfortran/AUTOMATIC-and-STATIC-attributes.html new file mode 100644 index 0000000..3cb1380 --- /dev/null +++ b/share/doc/gfortran/AUTOMATIC-and-STATIC-attributes.html @@ -0,0 +1,131 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html> +<!-- Copyright (C) 1999-2023 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). 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Copies published by the Free Software Foundation raise + funds for GNU development. --> +<!-- Created by GNU Texinfo 5.1, http://www.gnu.org/software/texinfo/ --> +<head> +<title>The GNU Fortran Compiler: AUTOMATIC and STATIC attributes</title> + +<meta name="description" content="The GNU Fortran Compiler: AUTOMATIC and STATIC attributes"> +<meta name="keywords" content="The GNU Fortran Compiler: AUTOMATIC and STATIC attributes"> +<meta name="resource-type" content="document"> +<meta name="distribution" content="global"> +<meta name="Generator" content="makeinfo"> +<meta http-equiv="Content-Type" content="text/html; charset=utf-8"> +<link href="index.html#Top" rel="start" title="Top"> +<link href="Option-Index.html#Option-Index" rel="index" title="Option Index"> +<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> +<link href="Extensions-implemented-in-GNU-Fortran.html#Extensions-implemented-in-GNU-Fortran" rel="up" title="Extensions implemented in GNU Fortran"> +<link href="Extended-math-intrinsics.html#Extended-math-intrinsics" rel="next" title="Extended math intrinsics"> +<link href="Type-variants-for-integer-intrinsics.html#Type-variants-for-integer-intrinsics" rel="previous" title="Type variants for integer intrinsics"> +<style type="text/css"> +<!-- +a.summary-letter {text-decoration: none} +blockquote.smallquotation {font-size: smaller} +div.display {margin-left: 3.2em} +div.example {margin-left: 3.2em} +div.indentedblock {margin-left: 3.2em} +div.lisp {margin-left: 3.2em} +div.smalldisplay {margin-left: 3.2em} +div.smallexample {margin-left: 3.2em} +div.smallindentedblock {margin-left: 3.2em; font-size: smaller} +div.smalllisp {margin-left: 3.2em} +kbd {font-style:oblique} +pre.display {font-family: inherit} +pre.format {font-family: inherit} +pre.menu-comment {font-family: serif} +pre.menu-preformatted {font-family: serif} +pre.smalldisplay {font-family: inherit; font-size: smaller} +pre.smallexample {font-size: smaller} +pre.smallformat {font-family: inherit; font-size: smaller} +pre.smalllisp {font-size: smaller} +span.nocodebreak {white-space:nowrap} +span.nolinebreak {white-space:nowrap} +span.roman {font-family:serif; font-weight:normal} +span.sansserif {font-family:sans-serif; font-weight:normal} +ul.no-bullet {list-style: none} +--> +</style> + + +</head> + +<body lang="en" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000"> +<a name="AUTOMATIC-and-STATIC-attributes"></a> +<div class="header"> +<p> +Next: <a href="Extended-math-intrinsics.html#Extended-math-intrinsics" accesskey="n" rel="next">Extended math intrinsics</a>, Previous: <a href="Type-variants-for-integer-intrinsics.html#Type-variants-for-integer-intrinsics" accesskey="p" rel="previous">Type variants for integer intrinsics</a>, Up: <a href="Extensions-implemented-in-GNU-Fortran.html#Extensions-implemented-in-GNU-Fortran" accesskey="u" rel="up">Extensions implemented in GNU Fortran</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p> +</div> +<hr> +<a name="AUTOMATIC-and-STATIC-attributes-1"></a> +<h4 class="subsection">5.1.25 <code>AUTOMATIC</code> and <code>STATIC</code> attributes</h4> +<a name="index-variable-attributes"></a> +<a name="index-AUTOMATIC"></a> +<a name="index-STATIC"></a> + +<p>With <samp>-fdec-static</samp> GNU Fortran supports the DEC extended attributes +<code>STATIC</code> and <code>AUTOMATIC</code> to provide explicit specification of entity +storage. These follow the syntax of the Fortran standard <code>SAVE</code> attribute. +</p> +<p><code>STATIC</code> is exactly equivalent to <code>SAVE</code>, and specifies that +an entity should be allocated in static memory. As an example, <code>STATIC</code> +local variables will retain their values across multiple calls to a function. +</p> +<p>Entities marked <code>AUTOMATIC</code> will be stack automatic whenever possible. +<code>AUTOMATIC</code> is the default for local variables smaller than +<samp>-fmax-stack-var-size</samp>, unless <samp>-fno-automatic</samp> is given. This +attribute overrides <samp>-fno-automatic</samp>, <samp>-fmax-stack-var-size</samp>, and +blanket <code>SAVE</code> statements. +</p> + +<p>Examples: +</p> +<div class="example"> +<pre class="example">subroutine f + integer, automatic :: i ! automatic variable + integer x, y ! static variables + save + ... +endsubroutine +</pre></div> +<div class="example"> +<pre class="example">subroutine f + integer a, b, c, x, y, z + static :: x + save y + automatic z, c + ! a, b, c, and z are automatic + ! x and y are static +endsubroutine +</pre></div> +<div class="example"> +<pre class="example">! Compiled with -fno-automatic +subroutine f + integer a, b, c, d + automatic :: a + ! a is automatic; b, c, and d are static +endsubroutine +</pre></div> + + + + +</body> +</html> |