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<h3 class="section">7.95 <code>.section </code><var>name</var></h3>
<p><a name="index-named-section-440"></a>Use the <code>.section</code> directive to assemble the following code into a section
named <var>name</var>.
<p>This directive is only supported for targets that actually support arbitrarily
named sections; on <code>a.out</code> targets, for example, it is not accepted, even
with a standard <code>a.out</code> section name.
<!-- only print the extra heading if both COFF and ELF are set -->
<h4 class="subheading">COFF Version</h4>
<p><a name="index-_0040code_007bsection_007d-directive-_0028COFF-version_0029-441"></a>For COFF targets, the <code>.section</code> directive is used in one of the following
ways:
<pre class="smallexample"> .section <var>name</var>[, "<var>flags</var>"]
.section <var>name</var>[, <var>subsection</var>]
</pre>
<p>If the optional argument is quoted, it is taken as flags to use for the
section. Each flag is a single character. The following flags are recognized:
<dl>
<dt><code>b</code><dd>bss section (uninitialized data)
<br><dt><code>n</code><dd>section is not loaded
<br><dt><code>w</code><dd>writable section
<br><dt><code>d</code><dd>data section
<br><dt><code>r</code><dd>read-only section
<br><dt><code>x</code><dd>executable section
<br><dt><code>s</code><dd>shared section (meaningful for PE targets)
<br><dt><code>a</code><dd>ignored. (For compatibility with the ELF version)
</dl>
<p>If no flags are specified, the default flags depend upon the section name. If
the section name is not recognized, the default will be for the section to be
loaded and writable. Note the <code>n</code> and <code>w</code> flags remove attributes
from the section, rather than adding them, so if they are used on their own it
will be as if no flags had been specified at all.
<p>If the optional argument to the <code>.section</code> directive is not quoted, it is
taken as a subsection number (see <a href="Sub_002dSections.html#Sub_002dSections">Sub-Sections</a>).
<!-- only print the extra heading if both COFF and ELF are set -->
<h4 class="subheading">ELF Version</h4>
<p><a name="index-Section-Stack-442"></a>This is one of the ELF section stack manipulation directives. The others are
<code>.subsection</code> (see <a href="SubSection.html#SubSection">SubSection</a>), <code>.pushsection</code>
(see <a href="PushSection.html#PushSection">PushSection</a>), <code>.popsection</code> (see <a href="PopSection.html#PopSection">PopSection</a>), and
<code>.previous</code> (see <a href="Previous.html#Previous">Previous</a>).
<p><a name="index-_0040code_007bsection_007d-directive-_0028ELF-version_0029-443"></a>For ELF targets, the <code>.section</code> directive is used like this:
<pre class="smallexample"> .section <var>name</var> [, "<var>flags</var>"[, @<var>type</var>[,<var>flag_specific_arguments</var>]]]
</pre>
<p>The optional <var>flags</var> argument is a quoted string which may contain any
combination of the following characters:
<dl>
<dt><code>a</code><dd>section is allocatable
<br><dt><code>w</code><dd>section is writable
<br><dt><code>x</code><dd>section is executable
<br><dt><code>M</code><dd>section is mergeable
<br><dt><code>S</code><dd>section contains zero terminated strings
<br><dt><code>G</code><dd>section is a member of a section group
<br><dt><code>T</code><dd>section is used for thread-local-storage
</dl>
<p>The optional <var>type</var> argument may contain one of the following constants:
<dl>
<dt><code>@progbits</code><dd>section contains data
<br><dt><code>@nobits</code><dd>section does not contain data (i.e., section only occupies space)
<br><dt><code>@note</code><dd>section contains data which is used by things other than the program
<br><dt><code>@init_array</code><dd>section contains an array of pointers to init functions
<br><dt><code>@fini_array</code><dd>section contains an array of pointers to finish functions
<br><dt><code>@preinit_array</code><dd>section contains an array of pointers to pre-init functions
</dl>
<p>Many targets only support the first three section types.
<p>Note on targets where the <code>@</code> character is the start of a comment (eg
ARM) then another character is used instead. For example the ARM port uses the
<code>%</code> character.
<p>If <var>flags</var> contains the <code>M</code> symbol then the <var>type</var> argument must
be specified as well as an extra argument&mdash;<var>entsize</var>&mdash;like this:
<pre class="smallexample"> .section <var>name</var> , "<var>flags</var>"M, @<var>type</var>, <var>entsize</var>
</pre>
<p>Sections with the <code>M</code> flag but not <code>S</code> flag must contain fixed size
constants, each <var>entsize</var> octets long. Sections with both <code>M</code> and
<code>S</code> must contain zero terminated strings where each character is
<var>entsize</var> bytes long. The linker may remove duplicates within sections with
the same name, same entity size and same flags. <var>entsize</var> must be an
absolute expression.
<p>If <var>flags</var> contains the <code>G</code> symbol then the <var>type</var> argument must
be present along with an additional field like this:
<pre class="smallexample"> .section <var>name</var> , "<var>flags</var>"G, @<var>type</var>, <var>GroupName</var>[, <var>linkage</var>]
</pre>
<p>The <var>GroupName</var> field specifies the name of the section group to which this
particular section belongs. The optional linkage field can contain:
<dl>
<dt><code>comdat</code><dd>indicates that only one copy of this section should be retained
<br><dt><code>.gnu.linkonce</code><dd>an alias for comdat
</dl>
<p>Note: if both the <var>M</var> and <var>G</var> flags are present then the fields for
the Merge flag should come first, like this:
<pre class="smallexample"> .section <var>name</var> , "<var>flags</var>"MG, @<var>type</var>, <var>entsize</var>, <var>GroupName</var>[, <var>linkage</var>]
</pre>
<p>If no flags are specified, the default flags depend upon the section name. If
the section name is not recognized, the default will be for the section to have
none of the above flags: it will not be allocated in memory, nor writable, nor
executable. The section will contain data.
<p>For ELF targets, the assembler supports another type of <code>.section</code>
directive for compatibility with the Solaris assembler:
<pre class="smallexample"> .section "<var>name</var>"[, <var>flags</var>...]
</pre>
<p>Note that the section name is quoted. There may be a sequence of comma
separated flags:
<dl>
<dt><code>#alloc</code><dd>section is allocatable
<br><dt><code>#write</code><dd>section is writable
<br><dt><code>#execinstr</code><dd>section is executable
<br><dt><code>#tls</code><dd>section is used for thread local storage
</dl>
<p>This directive replaces the current section and subsection. See the
contents of the gas testsuite directory <code>gas/testsuite/gas/elf</code> for
some examples of how this directive and the other section stack directives
work.
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