Re: Built-Using and Cython

[Jonathan Nieder <jrnieder@gmail.com>]

Nikolaus Rath wrote:
> Russ Allbery <rra@debian.org> writes:

>> The main thing we want to avoid is having Build-Using for every single
>> package in the archive because of libgcc, because that seems pointless and
>> annoying.  Similarly, I doubt we need that for the inline code in eglibc
>> headers, given that no one else does that and hasn't for years and years,
>> so regardless of the specific license text, it's pretty clear this isn't a
>> general upstream expectation.
>
> To me this all sounds as if packages using Cython in the build process
> *should* use Build-Using: cython then. Cython certainly doesn't have the
> same license exception that gcc has, and there also isn't much of a
> precedence (compared to eglibc).

Does code generated by Cython contain a *copy* of a significant portion
of Cython itself (for example a run-time system)?

If so, do the license conditions for copying that significant portion
require reproducing the exact version of the Cython source used along
with the generated code?

If so, then yes, such packages need to use Built-Using to ensure we
comply with the license by preserving old versions of cython when
appropriate in the archive.  But that would be very unusual.  Is there
any proprietary software written in Cython?  What do they do?

Thanks,
Jonathan