[Cython] build cython-devel on Windows fails if MSVC not available

[Stefan Behnel]

Lisandro Dalcin wrote:
> I tried to build && install cython-devel on Windows XP, I do not have
> MSVC installed. All went fine, but compiling extension modules
> (Scanners, Scanning, Parsing, Visitor) failed bad because the MSVC
> compiler was not available.
>
> Do it make sense to fix this by printing a warning and go on if the
> extension building fails for ever reason?

We already gracefully handle the case that the Cython compilation fails,
so, yes, that would be nice. It's harder to do, though, as it happens
inside the setup() call. Maybe we can figure out before-hand if a compiler
is available, or just default to not compiling on Windows.


> Unless a user actually open and take a look at setup.py, there is no
> way to discover the '--no-cython-compile' flag.

Yes, a good help message would be good.

Stefan