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[Bug tree-optimization/17064] -falias-noargument-global doesn't eliminate dead stores/loads



------- Comment #16 from rguenth at gcc dot gnu dot org  2009-04-03 11:57 -------
Re-confirmed with current trunk.  The issue is that PTA computes

Flow-insensitive points-to information for foo

p_1(D), points-to vars: { PARM_NOALIAS.28 } (includes global vars)

foo (int * p)
{
<bb 2>:
  *p_1(D) = 1;
  bar ();
  *p_1(D) = 2;
  return;

note the 'includes global vars' flag.  Note that "fixing" this would
really make _both_ stores to *p dead, as "does-not-point-to-global"
does not mean "does-point-to-local".

A more proper definition of the effect of this flag should be given.


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|2006-01-05 14:24:50         |2009-04-03 11:57:05
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17064


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