Re: [PATCH] Windows jobserver updates for GNU make 4.1

[Paul Smith]

On Tue, 2016-03-01 at 18:55 +0200, Eli Zaretskii wrote:
> > From: Troy Runkel <address@hidden>
> > CC: "address@hidden" <address@hidden>
> > Date: Tue, 1 Mar 2016 12:21:38 +0000
> > 
> > The changes for this patch were created by another developer where
> I work.  I've forwarded your questions to him and included his
> answers below.  Thanks!
> 
> Thanks.  But if changes were not written by you, how can we accept
> them, without knowing the name of that person and verifying we have a
> copyright assignment from him on file?  The changes are substantial
> enough to require legal papers.

I don't know if this is good or bad (although I can guess :)), but I'm
about to push changes (probably tonight) which extract all aspects of
the jobserver feature into platform-specific files.  So, this patch
will no longer apply at all... but hopefully the changes needed for
this feature will be much simpler to implement (in any event, they
should be cleaner to implement).

The main impetus for this is a change I want to make to the POSIX
implementation to allow us to use pselect() where available, which will
get rid of the SO_RESTART/SIGCHLD hack and increase reliability
(looking at https://savannah.gnu.org/bugs/index.php?46261 ).  I just
couldn't face another round of ever-more #ifdef'd code.

The POSIX jobserver code is now in posixos.c and the Windows code is
now in w32/w32os.c.  There is a single "os.h" header file that defines
the interface both support.

I've also added stub functions to vmsfunctions.c.  I need to look at
the AmigaOS support to see what needs to be done there.  OS2 is using
mainly the same interface as POSIX, weirdly enough.  I did a bit of
work to pull those changes into posixos.c.

I have built on Linux and will test on OSX.

I have built on Windows using both Visual Studio 14 (2015) and MinGW
GCC 4.9.3, with the build_w32.bat file (which I have completely
rewritten... hope that's OK).  I edited, but did not try to use, the
vcproj file to add the new file.

I am not able to test on VMS, AmigaOS, OS2, or DOS.

I'm not sure what to do about the plethora of other ways we can build
for Windows.  Do we still have any use for dosbuild.bat for example? 
 It seems to invoke gcc... does that mean it's superseded by the
build_w32.bat support for GCC builds?

I assume we still support NMakefile?

It's a little frustrating how many different methods we have to
support.  I wonder if we can somehow condense this... hmm.