From: Urabe Shyouhei <shyouhei@...>
Date: 2011-05-12T19:00:27+09:00
Subject: [ruby-core:36129] Re: [Ruby 1.9 - Bug #4666][Open] set ruby compatibility version to 1.9.3 in trunk

Hi lucas,

(05/12/2011 04:48 PM), Lucas Nussbaum wrote:
> However, I am still wondering whether 1.9.3 is really ABI-compatible
> with 1.9.{1,2}, which is required if we want to ship it as a drop-in
> replacement (same SONAME).

This is the point.  If we broke binary compatibility already, then it is WRONG
for us to ship 1.9.3 with compatibility version 1-9-1.  I wonder if that
situation (if any) is intentional or just an accident.

> I looked at the symbols exported by libruby.so in 1.9.2 and 1.9.3, and
> many symbols were removed (list below). Is that expected? Are they only
> symbols that were not supposed to be used by third-party libraries?

I think so.  These symbols are not listed in our C header files.  Until 1.9.2
you needed some tricks to reach to those symbols, like, manually calling
dlsym(3) or something.  I think that is beyond what "binary compatibility" is
meant.