https://gcc.gnu.org/bugzilla/show_bug.cgi?id=56007
--- Comment #6 from Harald Anlauf <anlauf at gmx dot de> ---
(In reply to Harald Anlauf from comment #5)
> The patch of comment #4 appears to be easily extendible to reject
> arrays as loop variables (I hope I got this right):
>
> Index: gcc/fortran/match.c
> ===================================================================
> --- gcc/fortran/match.c (revision 232904)
> +++ gcc/fortran/match.c (working copy)
> @@ -877,6 +877,18 @@
> if (m != MATCH_YES)
> return MATCH_NO;
>
> + if (var->ts.type == BT_CHARACTER)
> + {
> + gfc_error ("Loop variable at %C cannot be of type CHARACTER");
> + goto cleanup;
> + }
> +
> + if (var->symtree->n.sym->attr.dimension)
> + {
> + gfc_error ("Loop variable at %C cannot be an array");
> + goto cleanup;
> + }
> +
> /* F2008, C617 & C565. */
> if (var->symtree->n.sym->attr.codimension)
> {
The first part of the patch is actually not needed, thus the essential
part is:
Index: gcc/fortran/match.c
===================================================================
--- gcc/fortran/match.c (revision 232904)
+++ gcc/fortran/match.c (working copy)
@@ -877,6 +877,12 @@
if (m != MATCH_YES)
return MATCH_NO;
+ if (var->symtree->n.sym->attr.dimension)
+ {
+ gfc_error ("Loop variable at %C cannot be an array");
+ goto cleanup;
+ }
+
/* F2008, C617 & C565. */
if (var->symtree->n.sym->attr.codimension)
{
This removed the most confusing error messages, but leaves those
cases untouched where the parsing of the do statement should give
a syntax error.
Testsuite suggestions based on Tobias' examples:
% cat pr56007.f
! { dg-do compile }
! PR fortran/56007
! Based on testcase by Tobias Schlüter
integer iw1(90), doiw1(90)
do iw1(1)=1
do iw1=1
do iw1=1,2 ! { dg-error "cannot be an array" }
end do ! { dg-error "Expecting END PROGRAM statement" }
END
% cat pr56007.f90
! { dg-do compile }
! PR fortran/56007
! Based on testcase by Tobias Schlüter
integer iw1(90), doiw1(90)
do iw1=1,2 ! { dg-error "cannot be an array" }
end do ! { dg-error "Expecting END PROGRAM statement" }
do iw1(1)=1 ! { dg-error "Unclassifiable statement" }
do iw1=1 ! { dg-error "cannot be an array" }
end do ! { dg-error "Expecting END PROGRAM statement" }
END program
