Re: array bounds checking?

[Greg McGary <gkm at eng dot ascend dot com>]

Jeffrey A Law <law@hurl.cygnus.com> writes:

> My biggest concern is the change in pointer size; yes BP has
> mechanisms to handle this, but it just makes me uneasy.

It does take some getting used to.  Having a BP C library helps
immensely.

> It sounds like you use a CONCAT like rtx to represent a bounded
> pointer.  Is that correct?

I invented a new rtx CONCAT3.  I don't much like it and think both
special-cases CONCAT and CONCAT3 should be replaced with a
variable-length rtx where XEXP (foo, 0) is the length.

> If so, then we're going to need to actually fix the CONCAT support.
> It's got some problems right now.

Whatever you can tell me about CONCAT problems would be a great help.
I already fixed a few CONCAT bugs in 2.7.2.

> It would also be good to get some sense of the changes involved;
> particularly for front-ends.

As promised in an earlier message, I'll send you a useless patch you
can review.  (Useless because it's either for 2.7.2 or untested for
2.8.1)

> We'd want to be able to hook into the Fortran front end initially.
> The gpc guys would probably also benefit from this code, so we'll
> want them to be able to hook in as well.

What's "gpc"?  Pascal?