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Next: <a href="Writing-the-symbol-table.html#Writing-the-symbol-table" accesskey="n" rel="next">Writing the symbol table</a>, Previous: <a href="Information-provided-by-the-linker.html#Information-provided-by-the-linker" accesskey="p" rel="prev">Information provided by the linker</a>, Up: <a href="Performing-the-Final-Link.html#Performing-the-Final-Link" accesskey="u" rel="up">Performing the Final Link</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="BFD-Index.html#BFD-Index" title="Index" rel="index">Index</a>]</p>
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<a name="Relocating-the-section-contents-1"></a>
<h4 class="subsubsection">2.17.3.2 Relocating the section contents</h4>
<p>The <code>_bfd_final_link</code> function should look through the
<code>link_order</code> structures attached to each section of the
output file. Each <code>link_order</code> structure should either be
handled specially, or it should be passed to the function
<code>_bfd_default_link_order</code> which will do the right thing
(<code>_bfd_default_link_order</code> is defined in <code>linker.c</code>).
</p>
<p>For efficiency, a <code>link_order</code> of type
<code>bfd_indirect_link_order</code> whose associated section belongs
to a BFD of the same format as the output BFD must be handled
specially. This type of <code>link_order</code> describes part of an
output section in terms of a section belonging to one of the
input files. The <code>_bfd_final_link</code> function should read the
contents of the section and any associated relocs, apply the
relocs to the section contents, and write out the modified
section contents. If performing a relocatable link, the
relocs themselves must also be modified and written out.
</p>
<a name="index-_005fbfd_005frelocate_005fcontents"></a>
<a name="index-_005fbfd_005ffinal_005flink_005frelocate"></a>
<p>The functions <code>_bfd_relocate_contents</code> and
<code>_bfd_final_link_relocate</code> provide some general support for
performing the actual relocations, notably overflow checking.
Their arguments include information about the symbol the
relocation is against and a <code>reloc_howto_type</code> argument
which describes the relocation to perform. These functions
are defined in <code>reloc.c</code>.
</p>
<p>The a.out function which handles reading, relocating, and
writing section contents is <code>aout_link_input_section</code>. The
actual relocation is done in <code>aout_link_input_section_std</code>
and <code>aout_link_input_section_ext</code>.
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