Re: why does gcc jit require pthread?

[Jonathan Wakely <jwakely.gcc@gmail.com>]

On Tue, 15 Nov 2022 at 18:50, David Malcolm <dmalcolm@redhat.com> wrote:
>
> [Fixing typo in the Subject ("git" -> "jit" ); CCing jit mailing list]
>
> On Fri, 2022-11-11 at 17:16 +0000, Jonathan Wakely wrote:
> > On Mon, 7 Nov 2022 at 13:51, Jonathan Wakely wrote:
> > >
> > > On Mon, 7 Nov 2022 at 13:33, LIU Hao wrote:
> > > >
> > > > 在 2022-11-07 20:57, Jonathan Wakely 写道:
> > > > > It would be a lot nicer if playback::context met the C++
> > > > > Lockable
> > > > > requirements, and playback::context::compile () could just take
> > > > > a
> > > > > scoped lock on *this:
> > > > >
> > > > >
> > > >
> > > > Yeah yeah that makes a lot of sense. Would you please just commit
> > > > that? I don't have write access to
> > > > GCC repo, and it takes a couple of hours for me to bootstrap GCC
> > > > just for this tiny change.
> > >
> > > Somebody else needs to approve it first. I'll combine our patches
> > > and
> > > test and submit it properly for approval.
> >
> > Here's a complete patch that actually builds now, although I'm seeing
> > a stage 2 vs stage 3 comparison error which I don't have time to look
> > into right now.
>
> I confess that I'm not familiar with C++11's mutex and locking types,
> but having read through the relevant entries on cppreference.com, the
> patch looks correct to me.
>
> Are these classes well-supported on the minimum compiler version we
> support?  (Jonathan, I defer to your judgement here)

std::mutex has been supported since 4.4.0 and is very simple. The
implementation on trunk is identical to the one in gcc 4.8.5 except
for adding 'noexcept' to mutex::native_handle (), which is not
relevant to this change.

> Jonathan: you said in your followup email that it "bootstraps and
> passes testing on x86_64-pc-linux-gnu (CentOS 8 Stream)".  This is
> possibly a silly question, but did this testing include the jit
> testsuite?  A gotcha here is that --enable-languages=all does *not*
> enable jit.

Yes, I built with --enable-languages=c,c++,jit --enable-host-shared

> The patch is OK for trunk if you have favorable answers for the above
> two questions.
>
> Thanks!
> Dave
>