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| Next: <a href="Output-Section-Attributes.html#Output-Section-Attributes" accesskey="n" rel="next">Output Section Attributes</a>, Previous: <a href="Output-Section-Keywords.html#Output-Section-Keywords" accesskey="p" rel="prev">Output Section Keywords</a>, Up: <a href="SECTIONS.html#SECTIONS" accesskey="u" rel="up">SECTIONS</a> [<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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| <a name="Output-Section-Discarding-1"></a> |
| <h4 class="subsection">3.6.7 Output Section Discarding</h4> |
| <a name="index-discarding-sections"></a> |
| <a name="index-sections_002c-discarding"></a> |
| <a name="index-removing-sections"></a> |
| <p>The linker will not normally create output sections with no contents. |
| This is for convenience when referring to input sections that may or |
| may not be present in any of the input files. For example: |
| </p><div class="smallexample"> |
| <pre class="smallexample">.foo : { *(.foo) } |
| </pre></div> |
| <p>will only create a ‘<samp>.foo</samp>’ section in the output file if there is a |
| ‘<samp>.foo</samp>’ section in at least one input file, and if the input |
| sections are not all empty. Other link script directives that allocate |
| space in an output section will also create the output section. So |
| too will assignments to dot even if the assignment does not create |
| space, except for ‘<samp>. = 0</samp>’, ‘<samp>. = . + 0</samp>’, ‘<samp>. = sym</samp>’, |
| ‘<samp>. = . + sym</samp>’ and ‘<samp>. = ALIGN (. != 0, expr, 1)</samp>’ when |
| ‘<samp>sym</samp>’ is an absolute symbol of value 0 defined in the script. |
| This allows you to force output of an empty section with ‘<samp>. = .</samp>’. |
| </p> |
| <p>The linker will ignore address assignments (see <a href="Output-Section-Address.html#Output-Section-Address">Output Section Address</a>) |
| on discarded output sections, except when the linker script defines |
| symbols in the output section. In that case the linker will obey |
| the address assignments, possibly advancing dot even though the |
| section is discarded. |
| </p> |
| <a name="index-_002fDISCARD_002f"></a> |
| <p>The special output section name ‘<samp>/DISCARD/</samp>’ may be used to discard |
| input sections. Any input sections which are assigned to an output |
| section named ‘<samp>/DISCARD/</samp>’ are not included in the output file. |
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