From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andreas Enge <andreas@enge.fr>
Subject: Re: ccall mechanism in Julia
Date: Fri, 6 Mar 2015 23:25:16 +0100
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To: Ricardo Wurmus <ricardo.wurmus@mdc-berlin.de>
Cc: Guix-devel <guix-devel@gnu.org>

On Fri, Mar 06, 2015 at 04:48:59PM +0100, Ricardo Wurmus wrote:
> Julia's bindings to these libraries use the ccall mechanism; ccall
> builds a map from library names to paths by parsing the output of
> "ldconfig -p" at runtime.  I worked around this problem by patching the
> sources to include a static map of library names to store paths.  Then I
> noticed, however, that my patch effectively cripples the FFI.  It is no
> longer possible to call a function that is exported by a shared library
> unless it happens to be in the static map that is created at build time.

This looks like a good approach for guix, where we try to not use random
libraries lying around in the user profile. Setting the rpath with our
ld-wrapper behaves also like a static map. Otherwise, updating some other
library in the user profile would modify the behaviour of julia, which
would contradict our functional approach.

Or did I misunderstand anything?

Andreas