[Pkg-gauche-devel] [Gauche-devel] Gauche and bundled GC - still needed?

[Jens Thiele]

Shiro Kawai <shiro at lava.net> writes:

> From: Jens Thiele <karme at karme.de>
> Subject: Re: [Gauche-devel] Gauche and bundled GC - still needed?
> Date: Sun, 04 Nov 2012 09:09:11 +0100
>
>> what happens if gauche using the theoretical libgc-no-added-byte.so and
>> a gauche module using a library linked against the "standard" libgc.so
>> are used together? is that possible / will it cause problems?
>
> I haven't tried it, but it most likely won't work.  Two libgc
> will have their own data/bss areas, so the objects allocated
> in one libgc won't be tracked by another.  It's the same situation
> if the extention uses external gc by itself with the current
> Gauche.
>
> If I add a configure option to use system's libgc-no-added-byte.so
> in Gauche, the gauche-config/gauche-package scripts will take
> care of adding the same -l flag to the extensions.
>
> Requests to use system's libgc pop up time to time, so in general
> I feel it's worth to have such a configure option.

imho using the system libgc is the right thing to do. But I don't feel
like adding libgc-no-added-byte.so will really help then - in the end
all libs using libgc would have to be built in 2 versions and
DONT_ADD_BYTE_AT_END might not be the only reason to have a
bundled/"forked" version

ideally system libgc could be improved to satisfy all users (maybe
impossible?) but if one bundles / "forks" libgc one should take into
account that libgc is major portability headache

possible "solutions":
- system libgc must use DONT_ADD_BYTE_AT_END
  debian did this once? but doesn't anymore? don't know why
  (added debian libgc maintainer to cc)
- libgc somehow must be extended to support both options at the same
  time (don't know wether this is even possible?)
- gauche (mosh, bigloo, ...) must work without DONT_ADD_BYTE_AT_END
- get rid of libgc altogether
- stay with the current bundled/"forked" version and live with the
  resulting problems

similar discussion for mosh:
https://code.google.com/p/mosh-scheme/issues/detail?id=156

greetings,
karme