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Re: [patch, fortran] Fix PR29458 - spurious warning for implied do-loop counter


Daniel Franke wrote:
This code gives a warning about 'i' being used uninitialized:

  integer :: n, i
  n = 5
  n = SUM((/(i,i=1,n)/))
end

Attached patch fixes this by shadowing 'i' with a temporary variable. Further, it wraps the implied-do in its own block instead of placing it in the parent block directly. The relevant part now looks like this, 'i' is never touched:

{ shadow_loopvar.4 = 1;
D.1515 = n;
[...]
while (1)
{
if (shadow_loopvar.4 > D.1515) goto L.1;
(*(integer(kind=4)[0] *) atmp.2.data)[offset.3] = shadow_loopvar.4;
offset.3 = offset.3 + 1;
shadow_loopvar.4 = shadow_loopvar.4 + 1;
}
L.1:;
}

Excuse my ignorance, but what should happen if the user did: integer :: n, i n = 5 n = sum((/(i,i=1,n)/)) print *, i end That should print 5, shouldn't it?

Cheers,
- Tobi

2009-04-05 Daniel Franke <franke.daniel@gmail.com>

	PR fortran/29458
	* trans-array.c (gfc_trans_array_constructor_value): Shadow implied
	do-loop variable to avoid spurious middle-end warnings.

2009-04-05 Daniel Franke <franke.daniel@gmail.com>

	PR fortran/29458
	* gfortran.dg/implied_do_1.f90: New.


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