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Node:<a name="Symbol%20Value">Symbol Value</a>,

Next:<a rel="next" accesskey="n" href="Symbol-Type.html#Symbol%20Type">Symbol Type</a>,

Up:<a rel="up" accesskey="u" href="Symbol-Attributes.html#Symbol%20Attributes">Symbol Attributes</a>

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<h4 class="subsection">Value</h4>



   <p>The value of a symbol is (usually) 32 bits.  For a symbol which labels a

location in the text, data, bss or absolute sections the value is the

number of addresses from the start of that section to the label. 

Naturally for text, data and bss sections the value of a symbol changes

as <code>ld</code> changes section base addresses during linking.  Absolute

symbols' values do not change during linking: that is why they are

called absolute.



   <p>The value of an undefined symbol is treated in a special way.  If it is

0 then the symbol is not defined in this assembler source file, and

<code>ld</code> tries to determine its value from other files linked into the

same program.  You make this kind of symbol simply by mentioning a symbol

name without defining it.  A non-zero value represents a <code>.comm</code>

common declaration.  The value is how much common storage to reserve, in

bytes (addresses).  The symbol refers to the first address of the

allocated storage.



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