bug#30229: Python modules installed by pip in virtualenv can't find shared objects.

[Ricardo Wurmus <rekado@elephly.net>]

Hi,

> When a python module needs to load a dynamic shared object, it looks in the
> path provided by *LD_LIBRARY_PATH*(1), but guix doesn't modify this environment
> variable to export the needed path for python.

We cannot set this environment variable by default lest we break other
packages that may be installed.  LD_LIBRARY_PATH is dangerous as it
tells the runtime linker to prefer libraries in the specified
directories.

For Guix packages we use different means to embed store paths in
binaries, which are looked up at runtime.  For binaries that’s achieved
with RUNPATH; for others we patch the sources to ensure that libraries
are not looked up merely by name but by absolute path.

In your particular case (installing packages without Guix) I think the
best way is to manually set LD_LIBRARY_PATH on demand, or to set
LD_PRELOAD to the specific libraries that are required.

In general, though, I recommend using Guix for package management and
development instead of virtualenv and pip.

--
Ricardo

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