| <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> |
| <html> |
| <!-- Copyright (C) 1992-2015 Free Software Foundation, Inc. |
| Contributed by Cygnus Support. Written by Julia Menapace, Jim Kingdon, |
| and David MacKenzie. |
| |
| 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 no |
| Invariant Sections, with no Front-Cover Texts, and with no Back-Cover |
| Texts. A copy of the license is included in the section entitled "GNU |
| Free Documentation License". --> |
| <!-- Created by GNU Texinfo 5.2, http://www.gnu.org/software/texinfo/ --> |
| <head> |
| <title>STABS: Transformations On Global Variables</title> |
| |
| <meta name="description" content="STABS: Transformations On Global Variables"> |
| <meta name="keywords" content="STABS: Transformations On Global Variables"> |
| <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="Symbol-Types-Index.html#Symbol-Types-Index" rel="index" title="Symbol Types Index"> |
| <link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> |
| <link href="Transformations-On-Symbol-Tables.html#Transformations-On-Symbol-Tables" rel="up" title="Transformations On Symbol Tables"> |
| <link href="Stab-Section-Transformations.html#Stab-Section-Transformations" rel="next" title="Stab Section Transformations"> |
| <link href="Transformations-On-Static-Variables.html#Transformations-On-Static-Variables" rel="prev" title="Transformations On Static Variables"> |
| <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="Transformations-On-Global-Variables"></a> |
| <div class="header"> |
| <p> |
| Next: <a href="Stab-Section-Transformations.html#Stab-Section-Transformations" accesskey="n" rel="next">Stab Section Transformations</a>, Previous: <a href="Transformations-On-Static-Variables.html#Transformations-On-Static-Variables" accesskey="p" rel="prev">Transformations On Static Variables</a>, Up: <a href="Transformations-On-Symbol-Tables.html#Transformations-On-Symbol-Tables" accesskey="u" rel="up">Transformations On Symbol Tables</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Symbol-Types-Index.html#Symbol-Types-Index" title="Index" rel="index">Index</a>]</p> |
| </div> |
| <hr> |
| <a name="Transformations-on-Global-Variables"></a> |
| <h4 class="subsection">7.2.2 Transformations on Global Variables</h4> |
| |
| <p>Stabs for global variables do not contain location information. In |
| this case, the debugger finds location information in the assembler or |
| linker symbol table entry describing the variable. The source line: |
| </p> |
| <div class="example"> |
| <pre class="example">char g_foo = 'c'; |
| </pre></div> |
| |
| <p>generates the stab: |
| </p> |
| <div class="example"> |
| <pre class="example">.stabs "g_foo:G2",32,0,0,0 |
| </pre></div> |
| |
| <p>The variable is represented by two symbol table entries in the object |
| file (see below). The first one originated as a stab. The second one |
| is an external symbol. The upper case ‘<samp>D</samp>’ signifies that the |
| <code>n_type</code> field of the symbol table contains 7, <code>N_DATA</code> with |
| local linkage. The stab’s value is zero since the value is not used for |
| <code>N_GSYM</code> stabs. The value of the linker symbol is the relocatable |
| address corresponding to the variable. |
| </p> |
| <div class="example"> |
| <pre class="example">00000000 - 00 0000 GSYM g_foo:G2 |
| 00000080 D _g_foo |
| </pre></div> |
| |
| <p>These entries as transformed by the linker. The linker symbol table |
| entry now holds an absolute address: |
| </p> |
| <div class="example"> |
| <pre class="example">00000000 - 00 0000 GSYM g_foo:G2 |
| … |
| 0000e008 D _g_foo |
| </pre></div> |
| |
| |
| |
| |
| </body> |
| </html> |
