toolchain/share/doc/gdb/Symbol-Errors.html

128 lines
6.2 KiB
HTML
Raw Normal View History

2024-01-10 05:24:32 +00:00
<html lang="en">
<head>
<title>Symbol Errors - 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="GDB-Files.html#GDB-Files" title="GDB Files">
<link rel="prev" href="Index-Files.html#Index-Files" title="Index Files">
<link rel="next" href="Data-Files.html#Data-Files" title="Data Files">
<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="Symbol-Errors"></a>
<p>
Next:&nbsp;<a rel="next" accesskey="n" href="Data-Files.html#Data-Files">Data Files</a>,
Previous:&nbsp;<a rel="previous" accesskey="p" href="Index-Files.html#Index-Files">Index Files</a>,
Up:&nbsp;<a rel="up" accesskey="u" href="GDB-Files.html#GDB-Files">GDB Files</a>
<hr>
</div>
<h3 class="section">18.6 Errors Reading Symbol Files</h3>
<p>While reading a symbol file, <span class="sc">gdb</span> occasionally encounters problems,
such as symbol types it does not recognize, or known bugs in compiler
output. By default, <span class="sc">gdb</span> does not notify you of such problems, since
they are relatively common and primarily of interest to people
debugging compilers. If you are interested in seeing information
about ill-constructed symbol tables, you can either ask <span class="sc">gdb</span> to print
only one message about each such type of problem, no matter how many
times the problem occurs; or you can ask <span class="sc">gdb</span> to print more messages,
to see how many times the problems occur, with the <code>set
complaints</code> command (see <a href="Messages_002fWarnings.html#Messages_002fWarnings">Optional Warnings and Messages</a>).
<p>The messages currently printed, and their meanings, include:
<dl>
<dt><code>inner block not inside outer block in </code><var>symbol</var><dd>
The symbol information shows where symbol scopes begin and end
(such as at the start of a function or a block of statements). This
error indicates that an inner scope block is not fully contained
in its outer scope blocks.
<p><span class="sc">gdb</span> circumvents the problem by treating the inner block as if it had
the same scope as the outer block. In the error message, <var>symbol</var>
may be shown as &ldquo;<code>(don't know)</code>&rdquo; if the outer block is not a
function.
<br><dt><code>block at </code><var>address</var><code> out of order</code><dd>
The symbol information for symbol scope blocks should occur in
order of increasing addresses. This error indicates that it does not
do so.
<p><span class="sc">gdb</span> does not circumvent this problem, and has trouble
locating symbols in the source file whose symbols it is reading. (You
can often determine what source file is affected by specifying
<code>set verbose on</code>. See <a href="Messages_002fWarnings.html#Messages_002fWarnings">Optional Warnings and Messages</a>.)
<br><dt><code>bad block start address patched</code><dd>
The symbol information for a symbol scope block has a start address
smaller than the address of the preceding source line. This is known
to occur in the SunOS 4.1.1 (and earlier) C compiler.
<p><span class="sc">gdb</span> circumvents the problem by treating the symbol scope block as
starting on the previous source line.
<br><dt><code>bad string table offset in symbol </code><var>n</var><dd>
<a name="index-foo-1295"></a>Symbol number <var>n</var> contains a pointer into the string table which is
larger than the size of the string table.
<p><span class="sc">gdb</span> circumvents the problem by considering the symbol to have the
name <code>foo</code>, which may cause other problems if many symbols end up
with this name.
<br><dt><code>unknown symbol type 0x</code><var>nn</var><dd>
The symbol information contains new data types that <span class="sc">gdb</span> does
not yet know how to read. <code>0x</code><var>nn</var> is the symbol type of the
uncomprehended information, in hexadecimal.
<p><span class="sc">gdb</span> circumvents the error by ignoring this symbol information.
This usually allows you to debug your program, though certain symbols
are not accessible. If you encounter such a problem and feel like
debugging it, you can debug <code>gdb</code> with itself, breakpoint
on <code>complain</code>, then go up to the function <code>read_dbx_symtab</code>
and examine <code>*bufp</code> to see the symbol.
<br><dt><code>stub type has NULL name</code><dd>
<span class="sc">gdb</span> could not find the full definition for a struct or class.
<br><dt><code>const/volatile indicator missing (ok if using g++ v1.x), got...</code><dd>The symbol information for a C<tt>++</tt> member function is missing some
information that recent versions of the compiler should have output for
it.
<br><dt><code>info mismatch between compiler and debugger</code><dd>
<span class="sc">gdb</span> could not parse a type specification output by the compiler.
</dl>
</body></html>