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<h3 class="section">29.4 Custom Debug Info</h3>
<p><a name="index-custom-JIT-debug-info-3152"></a><a name="index-JIT-debug-info-reader-3153"></a>
Generating debug information in platform-native file formats (like ELF
or COFF) may be an overkill for JIT compilers; especially if all the
debug info is used for is displaying a meaningful backtrace. The
issue can be resolved by having the JIT writers decide on a debug info
format and also provide a reader that parses the debug info generated
by the JIT compiler. This section gives a brief overview on writing
such a parser. More specific details can be found in the source file
<samp><span class="file">gdb/jit-reader.in</span></samp>, which is also installed as a header at
<samp><var>includedir</var><span class="file">/gdb/jit-reader.h</span></samp> for easy inclusion.
<p>The reader is implemented as a shared object (so this functionality is
not available on platforms which don't allow loading shared objects at
runtime). Two <span class="sc">gdb</span> commands, <code>jit-reader-load</code> and
<code>jit-reader-unload</code> are provided, to be used to load and unload
the readers from a preconfigured directory. Once loaded, the shared
object is used the parse the debug information emitted by the JIT
compiler.
<ul class="menu">
<li><a accesskey="1" href="Using-JIT-Debug-Info-Readers.html#Using-JIT-Debug-Info-Readers">Using JIT Debug Info Readers</a>: How to use supplied readers correctly
<li><a accesskey="2" href="Writing-JIT-Debug-Info-Readers.html#Writing-JIT-Debug-Info-Readers">Writing JIT Debug Info Readers</a>: Creating a debug-info reader
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