Re: i370 port

["Ulrich Weigand" <uweigand@de.ibm.com>]

Paul Edwards wrote:

> In addition, that code has been ported to GCC 3.4.6, which is now
> working as a cross-compiler at least.  It's still some months away
> from working natively though.  It takes a lot of effort to convert
> the Posix-expecting GCC compiler into C90 compliance.  This has
> been done though, in a way that has minimal code changes to the
> GCC mainline.

You're referring to building GCC for a non-Posix *host*, right?
I assume those changes are not (primarily) in the back-end, but
throughout GCC common code?

> Yes, I'm aware that there is an S/390 port, but it isn't EBCDIC, isn't
> HLASM, isn't 370, isn't C90, isn't MVS.  It may well be possible to
> change all those things, and I suspect that in a few years from now
> I may be sending another message asking what I need to do to get 
> all my changes to the s390 target into the s390 target.  At that time,
> I suspect there will be a lot of objection to "polluting" the s390 target
> with all those "unnecessary" things.

Actually, I would really like to see the s390 target optionally support
the MVS ABI and HLASM assembler format, so I wouldn't have any objection
to patches that add these features ...

I understand current GCC supports various source and target character
sets a lot better out of the box, so it may be EBCDIC isn't even an
issue any more.   If there are other problems related to MVS host
support, I suppose those would need to be fixed in common code anyway,
no matter whether the s390 or i370 back-ends are used.

The only point in your list I'm sceptical about is 370 architecture
support -- I don't quite see why this is still useful today (the s390
port does require at a minimum a S/390 G2 with the branch relative
instructions ... but those have been around for nearly 15 years).

Bye,
Ulrich

-- 
  Dr. Ulrich Weigand
  GNU Toolchain for Linux on System z and Cell BE
  Ulrich.Weigand@de.ibm.com