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| <h3 class="section">4.5 bss Section</h3> |
| |
| <p><a name="index-bss-section-206"></a><a name="index-common-variable-storage-207"></a>The bss section is used for local common variable storage. |
| You may allocate address space in the bss section, but you may |
| not dictate data to load into it before your program executes. When |
| your program starts running, all the contents of the bss |
| section are zeroed bytes. |
| |
| <p>The <code>.lcomm</code> pseudo-op defines a symbol in the bss section; see |
| <a href="Lcomm.html#Lcomm"><code>.lcomm</code></a>. |
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| <p>The <code>.comm</code> pseudo-op may be used to declare a common symbol, which is |
| another form of uninitialized symbol; see <a href="Comm.html#Comm"><code>.comm</code></a>. |
| |
| <p>When assembling for a target which supports multiple sections, such as ELF or |
| COFF, you may switch into the <code>.bss</code> section and define symbols as usual; |
| see <a href="Section.html#Section"><code>.section</code></a>. You may only assemble zero values into the |
| section. Typically the section will only contain symbol definitions and |
| <code>.skip</code> directives (see <a href="Skip.html#Skip"><code>.skip</code></a>). |
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