Re: [boost] [EXTERNAL] [mpl] [build] [testing] Merge pull requests

Subject: Re: [boost] [EXTERNAL] [mpl] [build] [testing] Merge pull requests
From: Andrey Semashev (andrey.semashev_at_[hidden])
Date: 2014-09-19 02:27:32

On Friday 19 September 2014 03:54:47 Belcourt, Kenneth wrote:
> On Sep 17, 2014, at 12:39 PM, Andrey Semashev <andrey.semashev_at_[hidden]> 
wrote:
> > There were a lot of discussions about MPL recently, and I created a few
> > pull
> > requests to address issues:
> >
> > https://github.com/boostorg/boost/pull/39
> > 
> > Invoke 'headers' target before building testing tools. Note that several
> > testers are currently failing to run because of this problem. Since this
> > affects the testing process, I'd appreciate if someone familiar with it
> > could take a look.
> > 
> I’d like to revert the MPL PR that caused our testing problems, and the one
> Edward just applied.  It was wrong of me to commit the PR without any
> testing.  There’s been some list discussion but my overall concern is that
> we can’t clearly explain why some develop testers are broken and others are
> working okay.  The commit completely broke Darwin, Debian, FreeBSD, QNX and
> Windows.  But what’s really worrying is that some RHEL testers are still
> merrily cycling while other RHEL testers are broken.  Same for Ubuntu, some
> are cycling okay while some are broken.  I think it’s too risky to apply a
> patch when we, honestly I, don’t understand why this is happening.
> 
> While we could apply Andrey’s PR (below) I’m afraid that may mask real
> underlying problems that we may not find out about until this hits master,
> or worse, users.  I’ll work with Andrey to get the MPL changes applied,
> perhaps in smaller PRs.
> 
> Please let me know if you have concerns.

Kenneth, I've already explained why the problem has likely appeared, and 
moving back to the monolithic MPL is what covers it. It's not the fix.

I admit I don't know why implicit-dependency doesn't work in the tools 
Jamfile, but it is clear that the intention was to invoke 'headers' prior to 
building. That's what my second PR achieves, and I think this is the correct 
fix. Did you try it?

The problem with implicit-dependency should be investigated too, and Vladimir 
indicated in the PR that he wants to do that.

You can revert MPL if you still want to, but I honestly don't know how else 
(on the MPL side) we can do this.