Le 25/11/2021 à 21:03, Harald Anlauf a écrit :
Hi Mikael,
Am 25.11.21 um 17:46 schrieb Mikael Morin:
Hello,
Le 24/11/2021 à 22:32, Harald Anlauf via Fortran a écrit :
diff --git a/gcc/fortran/check.c b/gcc/fortran/check.c
index 5a5aca10ebe..837eb0912c0 100644
--- a/gcc/fortran/check.c
+++ b/gcc/fortran/check.c
@@ -4866,10 +4868,17 @@ gfc_check_reshape (gfc_expr *source, gfc_expr
*shape,
{
gfc_constructor *c;
bool test;
+ gfc_constructor_base b;
+ if (shape->expr_type == EXPR_ARRAY)
+ b = shape->value.constructor;
+ else if (shape->expr_type == EXPR_VARIABLE)
+ b = shape->symtree->n.sym->value->value.constructor;
This misses a check that shape->symtree->n.sym->value is an array, so
that it makes sense to access its constructor.
there are checks further above for the cases
shape->expr_type == EXPR_ARRAY
and for
shape->expr_type == EXPR_VARIABLE
which look at the elements of array shape to see if they are
non-negative.
Only in those cases where the full "if ()'s" pass we set
shape_is_const = true; and proceed. The purpose of the auxiliary
bool shape_is_const is to avoid repeating the lengthy if's again.
Only then the above cited code segment should get executed.
For shape->expr_type == EXPR_ARRAY there is really no change in logic.
For shape->expr_type == EXPR_VARIABLE the above snipped is now executed,
but then we already had
else if (shape->expr_type == EXPR_VARIABLE && shape->ref
&& shape->ref->u.ar.type == AR_FULL && shape->ref->u.ar.dimen == 1
&& shape->ref->u.ar.as
&& shape->ref->u.ar.as->lower[0]->expr_type == EXPR_CONSTANT
&& shape->ref->u.ar.as->lower[0]->ts.type == BT_INTEGER
&& shape->ref->u.ar.as->upper[0]->expr_type == EXPR_CONSTANT
&& shape->ref->u.ar.as->upper[0]->ts.type == BT_INTEGER
&& shape->symtree->n.sym->attr.flavor == FL_PARAMETER
&& shape->symtree->n.sym->value)
In which situations do I miss anything new?
Yes, I agree with all of this.
My comment wasn’t about a check on shape->expr_type, but on
shape->value->expr_type if shape->expr_type is a (parameter) variable.
Actually, this only supports the case where the parameter value is
defined by an array; but it could be an intrinsic call, a sum of
parameters, a reference to an other parameter, etc.
E.g. the following (still) does get rejected:
print *, reshape([1,2,3,4,5], a+1)
print *, reshape([1,2,3,4,5], a+a)
print *, reshape([1,2,3,4,5], 2*a)
print *, reshape([1,2,3,4,5], [3,3])
print *, reshape([1,2,3,4,5], spread(3,dim=1,ncopies=2))
and has been rejected before.
The usual way to handle this is to call gfc_reduce_init_expr which (pray
for it) will make an array out of whatever the shape expression is.
Can you give an example where it fails?
I think the current code would almost certainly fail, too.
Probably, I was just trying to avoid followup bugs. ;-)
I have checked the following:
integer, parameter :: a(2) = [1,1]
integer, parameter :: b(2) = a + 1
print *, reshape([1,2,3,4], b)
end
and it doesn’t fail as I thought it would.
So yes, I was wrong; b has been expanded to an array before.
Can you add an assert or a comment saying that the parameter value has
been expanded to a constant array?
Ok with that change.
