Obsolete powerpc*-*-*spe*

[David Edelsohn]

On Thu, Feb 16, 2017 at 3:53 PM, Sandra Loosemore
<sandra@codesourcery.com> wrote:
> On 02/16/2017 03:19 PM, Segher Boessenkool wrote:
>>
>> On Thu, Feb 16, 2017 at 02:49:47PM -0700, Sandra Loosemore wrote:
>>>>
>>>> I propose to mark powerpc*-*-*spe* as obsolete in GCC 7.  This includes
>>>> the spe.h installed header file, all the __builtin_spe* intrinsics, the
>>>> -mfloat-gprs= command-line option, and the support for the SPE ABIs.
>>>>
>>>> No one has properly tested these targets in a long time (the latest
>>>> testresults I could find are from July 2015, >1000 failures), and the
>>>> SPE support makes a lot of code much more complex.
>>>>
>>>> Any objections to this obsoletion?  GCC 7 will then be the last release
>>>> with support for SPE (it will need --enable-obsolete to build these
>>>> targets), and we will delete the SPE support during GCC 8 development.
>>>
>>>
>>> Can I ask that we hold off a bit before making a decision on this?
>>
>>
>> Of course, that is what we're doing in any case.
>>
>> Note that obsoleting it in GCC 7 means GCC 7 will still work, and that
>> we *can* remove it in GCC 8; we do not have to.  You have plenty of time
>> to find some way to keep SPE support in GCC.  The obsoletion notice _is_
>> the advance warning you're asking for.
>>
>> The gcc-7/changes.html text I'll propose later says:
>>
>>
>>    <li><p>Support for a number of older systems and recently
>>    unmaintained or untested target ports of GCC has been declared
>>    obsolete in GCC 7.  Unless there is activity to revive them, the
>>    next release of GCC will have their sources permanently
>>    <strong>removed</strong>.</p>
>>
>>    <p>The following ports for individual systems on
>>    particular architectures have been obsoleted:</p>
>>
>>    <ul>
>>      <li>PowerPC SPE (powerpc*-*-*spe*) as announced
>>      <a href="https://gcc.gnu.org/ml/gcc/2017-02/msg00041.html">
>>          here</a>.</li>
>>    </ul>
>>    </li>
>
>
> I understand that you're not going to remove the SPE support tomorrow. But
> that notice is going to scare users who depend on it, and I think it's not a
> good idea to scare users unnecessarily.  AFAIK GCC 7 is not going to be
> released tomorrow, either, so why not give folks a little more time to look
> into alternatives to announcing the support is being obsoleted?  IMO that
> should only be done when new maintainers have been solicited and nobody has
> come forward.

Sandra,

This is not a new issue.  The maintainer did not suddenly resign last
week.  There have been numerous efforts to reach out to the SPE
community for over a *decade*, cajoling them to step up with
maintenance for the port.  I am glad that this notice of obsolescence
has focused more attention on the long-standing problem.

Thanks, David