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<h3 class="section">18.4 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-1024"></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>

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