[Bug tree-optimization/47391] [4.5/4.6 Regression] read from const volatile incorrectly eliminated

[ebotcazou at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47391

Eric Botcazou <ebotcazou at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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                 CC|                            |ebotcazou at gcc dot
                   |                            |gnu.org

--- Comment #4 from Eric Botcazou <ebotcazou at gcc dot gnu.org> 2011-01-21 
09:19:42 UTC ---
> Untested fix.

tree_invariant_p_1 uses

  if (TREE_CONSTANT (t)
      || (TREE_READONLY (t) && !TREE_SIDE_EFFECTS (t)))
    return true;

rather than TREE_THIS_VOLATILE.