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| <a name="Format-Commands"></a> |
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| Next: <a href="REGION_005fALIAS.html#REGION_005fALIAS" accesskey="n" rel="next">REGION_ALIAS</a>, Previous: <a href="File-Commands.html#File-Commands" accesskey="p" rel="prev">File Commands</a>, Up: <a href="Simple-Commands.html#Simple-Commands" accesskey="u" rel="up">Simple Commands</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="Commands-Dealing-with-Object-File-Formats"></a> |
| <h4 class="subsection">3.4.3 Commands Dealing with Object File Formats</h4> |
| <p>A couple of linker script commands deal with object file formats. |
| </p> |
| <dl compact="compact"> |
| <dt><code>OUTPUT_FORMAT(<var>bfdname</var>)</code></dt> |
| <dt><code>OUTPUT_FORMAT(<var>default</var>, <var>big</var>, <var>little</var>)</code></dt> |
| <dd><a name="index-OUTPUT_005fFORMAT_0028bfdname_0029"></a> |
| <a name="index-output-file-format-in-linker-script"></a> |
| <p>The <code>OUTPUT_FORMAT</code> command names the BFD format to use for the |
| output file (see <a href="BFD.html#BFD">BFD</a>). Using <code>OUTPUT_FORMAT(<var>bfdname</var>)</code> is |
| exactly like using ‘<samp>--oformat <var>bfdname</var></samp>’ on the command line |
| (see <a href="Options.html#Options">Command Line Options</a>). If both are used, the command |
| line option takes precedence. |
| </p> |
| <p>You can use <code>OUTPUT_FORMAT</code> with three arguments to use different |
| formats based on the ‘<samp>-EB</samp>’ and ‘<samp>-EL</samp>’ command line options. |
| This permits the linker script to set the output format based on the |
| desired endianness. |
| </p> |
| <p>If neither ‘<samp>-EB</samp>’ nor ‘<samp>-EL</samp>’ are used, then the output format |
| will be the first argument, <var>default</var>. If ‘<samp>-EB</samp>’ is used, the |
| output format will be the second argument, <var>big</var>. If ‘<samp>-EL</samp>’ is |
| used, the output format will be the third argument, <var>little</var>. |
| </p> |
| <p>For example, the default linker script for the MIPS ELF target uses this |
| command: |
| </p><div class="smallexample"> |
| <pre class="smallexample">OUTPUT_FORMAT(elf32-bigmips, elf32-bigmips, elf32-littlemips) |
| </pre></div> |
| <p>This says that the default format for the output file is |
| ‘<samp>elf32-bigmips</samp>’, but if the user uses the ‘<samp>-EL</samp>’ command line |
| option, the output file will be created in the ‘<samp>elf32-littlemips</samp>’ |
| format. |
| </p> |
| </dd> |
| <dt><code>TARGET(<var>bfdname</var>)</code></dt> |
| <dd><a name="index-TARGET_0028bfdname_0029"></a> |
| <a name="index-input-file-format-in-linker-script"></a> |
| <p>The <code>TARGET</code> command names the BFD format to use when reading input |
| files. It affects subsequent <code>INPUT</code> and <code>GROUP</code> commands. |
| This command is like using ‘<samp>-b <var>bfdname</var></samp>’ on the command line |
| (see <a href="Options.html#Options">Command Line Options</a>). If the <code>TARGET</code> command |
| is used but <code>OUTPUT_FORMAT</code> is not, then the last <code>TARGET</code> |
| command is also used to set the format for the output file. See <a href="BFD.html#BFD">BFD</a>. |
| </p></dd> |
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