[Bug middle-end/52314] New: gimplifier produces volatile

[pinskia at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52314

             Bug #: 52314
           Summary: gimplifier produces volatile
    Classification: Unclassified
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: middle-end
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: pinskia@gcc.gnu.org


Noticed when improving tree-ssa-forwprop and other passes but is reproducible
on the trunk also.
Take:
volatile double bar;

int foo()
{
 double baz = -__builtin_huge_val();
 return baz <= -bar;
}
--- CUT ---
The gimple output is:
foo ()
{
  int D.1591;
  volatile double bar.0;
  volatile double D.1593;
  double baz;

  baz =  -Inf;
  bar.0 = bar;
  D.1593 = -bar.0;
  D.1591 = D.1593 >= baz;
  return D.1591;
}

--- CUT ---
The variables marked with volatile are wrongly marked as volatile.  Even though
those two decls are not marked with volatile, their types are.  When fold
happens, it sometimes wraps SAVE_EXPR around them because the whole volatile on
the type issue.