Re: compat32-* packages for Wine

[Greg Troxel <gdt%lexort.com@localhost>]

zerous <zerous@nocebo.space> writes:

> On Fri, Jul 12, 2019 at 07:26:35PM -0400, Greg Troxel wrote:
>> I would like to take a step back and look at the bigger picture of what
>> you are doing.  This seems hugely useful, but I'm not sure which way is
>> up.
>> 
>> You are talking about packages "which crosscompile programs for i386 on
>> amd64".  I would like to understand how that differs from
>> "crosscompiling a program for i386" separately from host architecture,
>> and if this is just a specific case of using generic crossbuild
>> infrastructure.
>
> I think crosscompiling a program for i386 separately from host
> architecture is the most generic way of looking at it. And yes,
> crosscompiling a program for i386 on amd64 is just a specific use-case
> that I focussed on owing to porting Wine to amd64.

We have a way to do cross compiling.  You seem not to be using it, and
reimplementing it somehow.  That is what I am trying to get at.

>> I wonder if the packages that are created are in fact the same as the
>> package that would be built on i386, modulo timestamps and other things
>> people worry about during reproducible builds.   And if not, why not.
>
> I don't know about this issue and I haven't come across it yet. I
> shall keep an eye out though.

I would suggest that you actively check.

>> I wonder if the wine you are building will be a 32-bit wine binary that
>> runs under netbsd32 emulation, and how that's different from the wine
>> built on i386.  I get it that you will have to make the netbsd32
>> emulation do a lot of complicated stuff that probably does not work now.
>> But I wonder how much of the 32-bit cross is about making wine work on
>> amd64, vs making it easy to build.
>>
>
> I am not trying to crosscompile wine 32-bit so that I can run it using
> compat_netbsd32. I have been trying to do a Wine WoW64 build which
> requires crosscompiling wine 32-bit, and using the latter to inject 32
> bit Wine libs, and whatever glue is required to make Wine 64-bit run
> 32-bit Windows applications on amd64.

I am not following.  Can you explain the big picture?  Is "64 bit wine"
about running windows programs compiled for an x86-64 processor on a
NetBSD/amd64 system?  Does this work, for native 64-bit programs,
without needing any i386 libs?  Is this entire exercise then about
supporting windows32 programs on NetBSD amd64?

And, if you just build the packages on netbsd/i386 system, and use the
libs from those, does that work?  I am trying to understand if the cross
compiling exercise is know to be sufficient and you have already made it
work by hand, or if there's something else going on.

If this is on some wiki or web page, that's even better and feel free to
tell me to go read it.

> Not at all :)
> I was just trying to get Wine WoW64 build to work as soon as possible,
> and was hoping to find the right approach of doing things in the
> process. I shall have a look at how we are handling linux packages and
> try to adapt it for 32 bit packages.

There are two parts: installing a foreign OS package, which we do for
Linux, and crossbuilding.  pkgsrc crossbuilding support is a little
rocky but the docs were improved in the last week or so.
See /usr/pkgsrc/mk/HOWTO-*-crosscompile.

I think it would be a far greater contribution to have a way to
cross-build  the packages you need via a generic approach, then to add a
dozen special-case packages to the tree.  I also think it will end up
being easier.