<html lang="en"> <head> <title>Old-style variable initialization - The GNU Fortran Compiler</title> <meta http-equiv="Content-Type" content="text/html"> <meta name="description" content="The GNU Fortran Compiler"> <meta name="generator" content="makeinfo 4.13"> <link title="Top" rel="start" href="index.html#Top"> <link rel="up" href="Extensions-implemented-in-GNU-Fortran.html#Extensions-implemented-in-GNU-Fortran" title="Extensions implemented in GNU Fortran"> <link rel="prev" href="Old_002dstyle-kind-specifications.html#Old_002dstyle-kind-specifications" title="Old-style kind specifications"> <link rel="next" href="Extensions-to-namelist.html#Extensions-to-namelist" title="Extensions to namelist"> <link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage"> <!-- Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 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="Old-style-variable-initialization"></a> <a name="Old_002dstyle-variable-initialization"></a> <p> Next: <a rel="next" accesskey="n" href="Extensions-to-namelist.html#Extensions-to-namelist">Extensions to namelist</a>, Previous: <a rel="previous" accesskey="p" href="Old_002dstyle-kind-specifications.html#Old_002dstyle-kind-specifications">Old-style kind specifications</a>, Up: <a rel="up" accesskey="u" href="Extensions-implemented-in-GNU-Fortran.html#Extensions-implemented-in-GNU-Fortran">Extensions implemented in GNU Fortran</a> <hr> </div> <h4 class="subsection">6.1.2 Old-style variable initialization</h4> <p>GNU Fortran allows old-style initialization of variables of the form: <pre class="smallexample"> INTEGER i/1/,j/2/ REAL x(2,2) /3*0.,1./ </pre> <p>The syntax for the initializers is as for the <code>DATA</code> statement, but unlike in a <code>DATA</code> statement, an initializer only applies to the variable immediately preceding the initialization. In other words, something like <code>INTEGER I,J/2,3/</code> is not valid. This style of initialization is only allowed in declarations without double colons (<code>::</code>); the double colons were introduced in Fortran 90, which also introduced a standard syntax for initializing variables in type declarations. <p>Examples of standard-conforming code equivalent to the above example are: <pre class="smallexample"> ! Fortran 90 INTEGER :: i = 1, j = 2 REAL :: x(2,2) = RESHAPE((/0.,0.,0.,1./),SHAPE(x)) ! Fortran 77 INTEGER i, j REAL x(2,2) DATA i/1/, j/2/, x/3*0.,1./ </pre> <p>Note that variables which are explicitly initialized in declarations or in <code>DATA</code> statements automatically acquire the <code>SAVE</code> attribute. </body></html>