Re: Using Py_SetPythonHome

John Gilmore
2012-10-04T07:33:10Z

Package management is a sinkhole, unfortunately. The OLPC project has
unfortunately discovered that despite the great support in the GNU
tools for cross-compilation, the Fedora package management tools are
completely incapable of cross-compilation. So now that they are
making hardware with three architectures to build software for (i386,
i686, and ARM), they need to dedicate three kinds of hardware to
building their Fedora-based releases. They can't make an OS image on
a fast x86 machine that will install or boot on an ARM.(*)

(I think Debian/Ubuntu package managers suffer from the same problem;
they all assume they're running "native", they run package-specific
shell scripts that think they're running in the target environment,
etc.)

I recommend NOT assuming that package managers are the cat's pajamas
and that therefore we can all skip the ability to usefully build from
source.

Having seen this Py_SetPythonHome discussion drag on for what seems
months (I think it's the most frequent subject line in the mailing
list), and yet I still don't understand why y'all care, perhaps someone
should try to write up a solid proposal that explains what the hell is
going on, with pros and cons listed and generally agreed upon. That
might help point a path to making a decision that sticks for a while.

John

(*): They can run builds under QEMU on x86, emulating the ARM
instruction set, using a set of native ARM compilers and a full ARM
GNU/Linux virtual machine, and make the ARM builds that way. Indeed they
do -- it's only a 2- to 3-times slowdown, which is far easier than
rewriting the package management subsystem for cross-compilation and
then getting the changes adopted "upstream" into Fedora. And far, far
easier than building fast hardware based on an available ARM chip.