Re: C++ conversion status update

Pedro Alves
2016-04-13T00:25:40Z

On 12/14/2015 07:09 PM, Pedro Alves wrote:
> On 12/14/2015 02:40 PM, Yao Qi wrote:
>> Pedro Alves <palves@redhat.com> writes:
>
>
>> We need a wiki page to track these hosts on which we enabled C++ build.
>> Like this gcc wiki page, https://gcc.gnu.org/wiki/CppBuildStatus or we
>> can track them in existing https://sourceware.org/gdb/wiki/cxx-conversion
>> wiki page.
>
> Ok.
>
>>
>>> The plan I propose next is to default to building in C++ mode on hosts
>>> that are known to build cleanly in C++ mode. Or rather, change the default
>>> to be C++ mode, _except_ for hosts/ports that haven't been converted
>>> yet.
>>
>> I prefer the latter.
>>
>>> Then, as ports get converted, one by one they'll be removed from
>>> the "can't do C++ yet" list. That gives us a defined stopping point -- when
>>> the list becomes empty, and after a reasonable period, we can decide to remove
>>> support for building in C mode and start making use of C++ features.
>>
>> That sounds good to me.
>
> Ok, that's my preference as well.
>
>>
>>>
>>> The question I have is which hosts (Architecture + OS combination) people
>>> care about that still need C++ conversion work and thus should be on
>>> that list?
>>
>> How about all linux and mingw hosts? assuming that xtensa can be
>> converted.
>
> x86-64 and x86 mingw built cleanly last I tried.
>
> I don't know about _all_ Linux hosts, hence the RFH.
>
> At least x86, x86_64, Aarch64, ARM, and PPC64 build cleanly. Or did, a
> few weeks back.
>
>>>
>>> This is where anyone can help!
>>>
>>> I've created the "users/palves/cxx-conversion" branch (on sourceware.org)
>>> where I committed a patch that implements the list idea. I filled in
>>> a set of hosts that I _thought_ wouldn't build, but I don't really know
>>> for sure.
>>>
>>> So I'd like to invite people to try to build master on their favorite
>>> host with --enable-build-with-cxx, and report back the result.
>>
>> We didn't hear anything on this yet, but we can't wait for it forever.
>
> Yeah. I got enthusiastic support offlist for C++ in general, but people
> don't seem to really be that interested or paying attention to random
> host architectures.
>

Now that the "exceptions signals handlers" issue is resolved, I think we've
now done all we could re. C++ conversion while keeping C supported as well.

I think the time has come to starting to default to building in C++ mode
on all hosts, except those known to not having been fully converted yet,
as with the patch at the top of the users/palves/cxx-conversion branch.

Thoughts?

Thanks,
Pedro Alves