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| <h4 class="subsection">3.6.7 Output Section Discarding</h4> |
| |
| <p><a name="index-discarding-sections-492"></a><a name="index-sections_002c-discarding-493"></a><a name="index-removing-sections-494"></a>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: |
| <pre class="smallexample"> .foo : { *(.foo) } |
| </pre> |
| <p class="noindent">will only create a ‘<samp><span class="samp">.foo</span></samp>’ section in the output file if there is a |
| ‘<samp><span class="samp">.foo</span></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><span class="samp">. = 0</span></samp>’, ‘<samp><span class="samp">. = . + 0</span></samp>’, ‘<samp><span class="samp">. = sym</span></samp>’, |
| ‘<samp><span class="samp">. = . + sym</span></samp>’ and ‘<samp><span class="samp">. = ALIGN (. != 0, expr, 1)</span></samp>’ when |
| ‘<samp><span class="samp">sym</span></samp>’ is an absolute symbol of value 0 defined in the script. |
| This allows you to force output of an empty section with ‘<samp><span class="samp">. = .</span></samp>’. |
| |
| <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-g_t_002fDISCARD_002f-495"></a>The special output section name ‘<samp><span class="samp">/DISCARD/</span></samp>’ may be used to discard |
| input sections. Any input sections which are assigned to an output |
| section named ‘<samp><span class="samp">/DISCARD/</span></samp>’ are not included in the output file. |
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