Re: Deprecate 32-bits HP-PA for GCC 4.8?

[John David Anglin <dave dot anglin at bell dot net>]

On 5/7/2012 1:33 PM, Steven Bosscher wrote:
> Hello,
>
> GCC is well into stage 1 for GCC 4.8, but I haven't seen any proposals
> for targets to be deprecated. I have one I would like to put on the
> list, so here's something to start a discussion with:
>
> Deprecate all support for 32-bits HP-PA. This includes HP-UX10, and
> PA-7000 and older.
>
>
> To name a few reasons:
>
> 1. Support for the last production release (HP-UX 10.20) ended on June
> 30, 2003. That will be 10 years ago by the time GCC 4.9 will be
> released. The only target architecture supported for HP-UX 10 is
> HP-PA. I think it's reasonable to assume that most users of HP-UX10 on
> machines with PA-RISC 2.0 support will have upgraded to HP-UX 11.11 or
> later.
>
> 2. HP-UX 10 is also the last target that only supports SJLJ exceptions.
>
> 3. The PA-7000 series only run HP-UX 10 or earlier, so support for
> HP-7000 and older is pointless without HP-UX10 support.
I believe it is reasonable to deprecate HP-UX 10.  However, this isn't 
much of
a cleanup.

> 4. 32-bits HP-PA uses the SOM binary object format, i.e. it is a
> non-ELF target (64-bits HP-PA is ELF).
I disagree with point 4.  The 32-bit code can't be removed without 
breaking the
Linux target (ELF 32).  Having built thousands of Debian packages, I know
this port is pretty solid.

Even for HP-UX, I believe the 32-bit port is more widely used than the 
64-bit target.
It also supports Ada and Java which haven't been ported to
the 64 the 64 bit target.
> Removing support for anything older than PA-8000 results in a
> considerable cleanup for the PA architecture: ~3300 lines out of
> ~23000, estimated by cleaning all "!TARGET_64BIT" and "TARGET_PA_11"
> patterns in pa.md and pa.c, and most of the cleanups to remove support
> for SOM objects.
>
> The resulting PA port would support HP-UX11 on 64bits PA-RISC 2.0
> (i.e. HP-PA8xxx).
>
>
> It's hard enough to maintain HP-UX11 support on HP-PA. With this
> cleanup, the job would become a bit simpler.
>
> Thoughts/comments?
>
> Ciao!
> Steven

Dave

--
John David Anglin    dave.anglin@bell.net