<html lang="en">
<head>
<title>Jumping - Debugging with GDB</title>
<meta http-equiv="Content-Type" content="text/html">
<meta name="description" content="Debugging with GDB">
<meta name="generator" content="makeinfo 4.13">
<link title="Top" rel="start" href="index.html#Top">
<link rel="up" href="Altering.html#Altering" title="Altering">
<link rel="prev" href="Assignment.html#Assignment" title="Assignment">
<link rel="next" href="Signaling.html#Signaling" title="Signaling">
<link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage">
<!--
Copyright (C) 1988-2019 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 ``Free Software'' and ``Free Software Needs
Free Documentation'', with the Front-Cover Texts being ``A GNU Manual,''
and with the Back-Cover Texts as in (a) below.

(a) The FSF's Back-Cover Text is: ``You are free to copy and modify
this GNU Manual.  Buying copies from GNU Press supports the FSF in
developing GNU and promoting software freedom.''
-->
<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="Jumping"></a>
<p>
Next:&nbsp;<a rel="next" accesskey="n" href="Signaling.html#Signaling">Signaling</a>,
Previous:&nbsp;<a rel="previous" accesskey="p" href="Assignment.html#Assignment">Assignment</a>,
Up:&nbsp;<a rel="up" accesskey="u" href="Altering.html#Altering">Altering</a>
<hr>
</div>

<h3 class="section">17.2 Continuing at a Different Address</h3>

<p>Ordinarily, when you continue your program, you do so at the place where
it stopped, with the <code>continue</code> command.  You can instead continue at
an address of your own choosing, with the following commands:

     
<a name="index-jump-1168"></a>
<a name="index-j-_0040r_007b_0028_0040code_007bjump_007d_0029_007d-1169"></a>
<dl><dt><code>jump </code><var>location</var><dt><code>j </code><var>location</var><dd>Resume execution at <var>location</var>.  Execution stops again immediately
if there is a breakpoint there.  See <a href="Specify-Location.html#Specify-Location">Specify Location</a>, for a description
of the different forms of <var>location</var>.  It is common
practice to use the <code>tbreak</code> command in conjunction with
<code>jump</code>.  See <a href="Set-Breaks.html#Set-Breaks">Setting Breakpoints</a>.

     <p>The <code>jump</code> command does not change the current stack frame, or
the stack pointer, or the contents of any memory location or any
register other than the program counter.  If <var>location</var> is in
a different function from the one currently executing, the results may
be bizarre if the two functions expect different patterns of arguments or
of local variables.  For this reason, the <code>jump</code> command requests
confirmation if the specified line is not in the function currently
executing.  However, even bizarre results are predictable if you are
well acquainted with the machine-language code of your program. 
</dl>

   <p>On many systems, you can get much the same effect as the <code>jump</code>
command by storing a new value into the register <code>$pc</code>.  The
difference is that this does not start your program running; it only
changes the address of where it <em>will</em> run when you continue.  For
example,

<pre class="smallexample">     set $pc = 0x485
</pre>
   <p class="noindent">makes the next <code>continue</code> command or stepping command execute at
address <code>0x485</code>, rather than at the address where your program stopped. 
See <a href="Continuing-and-Stepping.html#Continuing-and-Stepping">Continuing and Stepping</a>.

   <p>The most common occasion to use the <code>jump</code> command is to back
up&mdash;perhaps with more breakpoints set&mdash;over a portion of a program
that has already executed, in order to examine its execution in more
detail.

<!-- @group -->
   </body></html>