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<a name="HPPA-ELF32"></a>
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<p>
Next: <a href="M68K.html#M68K" accesskey="n" rel="next">M68K</a>, Previous: <a href="ARM.html#ARM" accesskey="p" rel="prev">ARM</a>, Up: <a href="Machine-Dependent.html#Machine-Dependent" accesskey="u" rel="up">Machine Dependent</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="LD-Index.html#LD-Index" title="Index" rel="index">Index</a>]</p>
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<hr>
<a name="ld-and-HPPA-32_002dbit-ELF-Support"></a>
<h3 class="section">4.5 <code>ld</code> and HPPA 32-bit ELF Support</h3>
<a name="index-HPPA-multiple-sub_002dspace-stubs"></a>
<a name="index-_002d_002dmulti_002dsubspace"></a>
<p>When generating a shared library, <code>ld</code> will by default generate
import stubs suitable for use with a single sub-space application.
The &lsquo;<samp>--multi-subspace</samp>&rsquo; switch causes <code>ld</code> to generate export
stubs, and different (larger) import stubs suitable for use with
multiple sub-spaces.
</p>
<a name="index-HPPA-stub-grouping"></a>
<a name="index-_002d_002dstub_002dgroup_002dsize_003dN-1"></a>
<p>Long branch stubs and import/export stubs are placed by <code>ld</code> in
stub sections located between groups of input sections.
&lsquo;<samp>--stub-group-size</samp>&rsquo; specifies the maximum size of a group of input
sections handled by one stub section.  Since branch offsets are signed,
a stub section may serve two groups of input sections, one group before
the stub section, and one group after it.  However, when using
conditional branches that require stubs, it may be better (for branch
prediction) that stub sections only serve one group of input sections.
A negative value for &lsquo;<samp>N</samp>&rsquo; chooses this scheme, ensuring that
branches to stubs always use a negative offset.  Two special values of
&lsquo;<samp>N</samp>&rsquo; are recognized, &lsquo;<samp>1</samp>&rsquo; and &lsquo;<samp>-1</samp>&rsquo;.  These both instruct
<code>ld</code> to automatically size input section groups for the branch types
detected, with the same behaviour regarding stub placement as other
positive or negative values of &lsquo;<samp>N</samp>&rsquo; respectively.
</p>
<p>Note that &lsquo;<samp>--stub-group-size</samp>&rsquo; does not split input sections.  A
single input section larger than the group size specified will of course
create a larger group (of one section).  If input sections are too
large, it may not be possible for a branch to reach its stub.
</p>


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