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   9 <title>section 4.7: Register Variables</title>
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  15 <H2>section 4.7: Register Variables</H2>
  16
  17 page 83
  18 <p>The <TT>register</TT> keyword is only a hint.
  19 The compiler might not put something in a register even though you ask it to,
  20 and
  21 it
  22 might put something in a register even though you don't ask it to.
  23 Most modern compilers do a good job of deciding when to put
  24 things in registers,
  25 so most of the time,
  26 you don't need to worry about it,
  27 and you don't have to use the <TT>register</TT> keyword at all.
  28 </p><p>(A note to assembly language programmers:
  29 there's no way to specify which register
  30 a <TT>register</TT> variable gets assigned to.
  31 Also,
  32 when you specify a function parameter as <TT>register</TT>,
  33 it just means that the local copy of the parameter
  34 should be copied to a register if possible;
  35 it does <em>not</em> necessarily indicate
  36 that the parameter is going to be passed in a register.)
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