Re: Building snapshot versions for Windows

[Philip Nienhuis]

Clemens Buchacher wrote:
> On Sun, May 05, 2013 at 11:31:35AM -0700, PhilipNienhuis wrote:
> > > I managed to complete the build by applying the attached patch to
> > > mxe-octave. I had to upgrade to gcc 4.8.0, because gcc 4.7.2 does not
> > > build with texinfo 5.0, which is the current version installed by Arch
> > > Linux. Backporting the fix needed to 4.7.2 is a much larger patch than
> > > the one needed to get gcc 4.8.0 to build with mxe-octave. But gcc 4.8.0
> > > currently breaks C++ mex files [2], so you may want to wait until that
> > > bug is fixed.
> >
> > Sorry I got lost here. Didn't you mix up MinGW and MXE?
> > MXE is for cross-compiling a Windows build in Linux; AFAIK it still invokes
> > gcc 4.7.2.
>
> Maybe I am confused about something, but it is my impression that the
> gcc for Windows built by MXE _is_ the MinGW gcc.
>
> Normally, MXE builds gcc 4.7.2. That is not possible on my machine
> because gcc's build system as of that version breaks with texinfo
> version 5.0 installed on the host.

Am I still missing something? I'm at loss what a locally installed 
texinfo 5.0 has to do with an MXE build.

MXE-octave downloads and installs texinfo 4.13a and uses that for the 
MXE build. In fact MXE downloads & builds all dependencies needed for 
the Windows build; it's a fairly closed system, separate from your 
native Linux. It has to be, otherwise MXE will break on the plethora of 
natively installed SW versions on each and every development box.
Just have a look in ./mxe-octave/pkg/ or ./mxe-octave/index.html to see 
what dependencies are downloaded, built and invoked to build Octave.

Anyway trying the example in bug #37122 with tonight's MXE build on 
Windows XP gets you this:

>> cd c:/tmp/mex
>> mex mex_test.c subdir/f.c subdir/g.c
mex_test.c:3:36: error: declaration of 'plhs' as array of voids
mex_test.c:3:68: error: declaration of 'prhs' as array of voids
g++: error: mex_test.o: No such file or directory
warning: unable to find mkoctfile in expected location: 
'X:\Octave\octave-3.7.3+_MXE\bin\mkoctfile-3.7.3+'
warning: mkoctfile exited with failure status
>>

Apparently there are errors in the example itself.
The mkoctfile warning is a bit misleading, AFAICS it always occurs when 
there are compile errors.

<snip>
> > > Unfortunately, I can only test the Windows build at work, since I do not
> > > have any Windows machines at home. How do you guys test your Windows
> > > builds?
> >
> > VirtualBox?
>
> I only have OEM versions, and I don't think I am allowed to install
> those in VirtualBox. Oh well, I guess I'll test it at work then.

Ah there's the problem. Non-free operating system.

One can legally buy second hand Windows licenses for a very small price 
on e.g., eBay. Although MS forbids that in the EULA, that clause has 
been overturned in European courts.
If you care you could try ReactOS, that project even has complete 
virtual machines for download; but I wonder if it could run a big 
program like Octave at all (I never tried).

I'm away next week, so I'm afraid I have very little opportunity to help 
you further until mid-May.

Philip