From: Pavel Raiskup <praiskup@redhat.com>
To: PostgreSQL Hacker <pgsql-hackers@postgresql.org>
Cc: devrim@gunduz.org
Subject: plruby: rb_iterate symbol clash with libruby.so
Date: Sat, 03 Nov 2018 17:19:40 +0100
Message-ID: <4738198.8KVIIDhgEB@nb.usersys.redhat.com>
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Hi, I'm curious how it worked before (seems like the function is defined
in both PostgreSQL and Ruby projects for quite some time) - but I recently
came across this situation:

    - /bin/postgres is build-time linked with 'ld -E'
    - /bin/postgres dlopen()s plruby.so
    - plruby.so calls rb_iterate, but linker prefers rb_iterate defined in
      /bin/postgres, instead of (the wanted one) rb_iterate from libruby.so

This means an ugly PG server crash.  I'm curious what to do with this;
ideally it would be solvable from plruby.so itself, but there doesn't seem
to be nice solution (one could do some hacks with dlopen('libruby.so')).

Is it realistic we could rename red-black tree methods from 'rb_*' to e.g.
'rbt_*' to avoid this clash?

Pavel