https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86322
--- Comment #5 from Steve Kargl ---
On Tue, Jan 08, 2019 at 09:40:29PM +, sgk at troutmask dot
apl.washington.edu wrote:
>
> Naw, it is is not due to my patch. Rather my patch has
> exposed or uncovered a bug in gfortran. gfortran needs
> to check
>
> F2018:C877 (R839) A data-i-do-object or a variable that appears as a
>data-stmt-object shall not be an object designator in which a pointer
>appears other than as the entire rightmost part-ref .
>
> In decl.c (gfc_match_data), gfortran needs a check for C877.
> I haven't gotten around to fixing this yet, and I likely won't
> for the foreseeable future.
>
Index: gcc/fortran/decl.c
===
--- gcc/fortran/decl.c (revision 267735)
+++ gcc/fortran/decl.c (working copy)
@@ -655,6 +655,15 @@ gfc_match_data (void)
"near %C in DATA statement");
goto cleanup;
}
+
+ if (e->symtree->n.sym->ts.type == BT_DERIVED
+ && e->symtree->n.sym->attr.pointer
+ && e->ref->type == REF_COMPONENT)
+ {
+ gfc_error ("part-ref with pointer attribute near %L is not "
+"rightmost component of data-stmt-object", >where);
+ goto cleanup;
+ }
}
m = top_val_list (new_data);
The above is marginally correct. It may be a starting point for
someone who cares about this bug and wants to fix it. The patch
checks if the leftmost part-ref has the pointer attribute and
the variable is a REF_COMPONENT, which means that a part-ref
other than the rightmost component has the pointer attribute.
This is the simple case. A better patch would need to check
each part-ref for the pointer attribute. That is none of a, b,
c, d, or e in a%b%c%d%e%i can have a pointer attribute.
Note, this works
program bar
type a
integer, pointer :: i
end type a
type b
type(a) j
end type b
integer, target, save :: k = 42
type(b) x
data x%j%i/k/
print *, x%j%i
end program bar
This gives an ICE like the one reported in this PR. 'j'
has the pointer attribute and so the program should be
rejected.
program bah
type a
integer :: i
end type a
type b
type(a), pointer :: j
end type b
integer, target, save :: k = 42
type(b) x
data x%j%i /k/
print *, x%j%i
end program bah
