Re: [gfortran,commited] Don't perform bounds-checking on assumed-size arrays

[Brooks Moses <bmoses at stanford dot edu>]

FX Coudert wrote:
> I just reviewed and commited Andrew's patch for PR fortran/19777  
> (http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19777), proposed on  
> bugzilla. It's a simple one-line that disables bounds-checking when  
> accessing elements of a assumed-size array:
>
> > --- trunk/gcc/fortran/trans-array.c	2006/05/27 09:06:01	114152
> > +++ trunk/gcc/fortran/trans-array.c	2006/05/27 09:41:42	114153
> > @@ -1948,7 +1948,7 @@
> >       gfc_conv_expr_type (&indexse, ar->start[n],  
> > gfc_array_index_type);
> >       gfc_add_block_to_block (&se->pre, &indexse.pre);
> >
> > -      if (flag_bounds_check)
> > +      if (flag_bounds_check && ar->as->type != AS_ASSUMED_SIZE)
> > 	{
> > 	  /* Check array bounds.  */
> > 	  tree cond;

This doesn't do any bounds checking at all for an assumed-size array, 
however, while all but the last exponent of an assumed-size array should 
in theory be checkable.  Would making the check

      if (flag_bounds_check && (ar->as->type != AS_ASSUMED_SIZE
        || n < ar->dimen - 1))

work correctly for checking the lower dimensions?

- Brooks