5.2 compatibility with 5.1?

[Jacques Vidrine]

gwk at rahn-koltermann.de said the following on 12/15/03 4:18 AM:

> Hi,
> 
> I installed 5.2-RC1 and wanted to run my Emacs binary from the 5.1
> system.
> 
> However, 5.2-RC1 has libutil.so.4 while 5.1 had libutil.so.3.  This was
> of course easy to workaround by symlinking libutil.so.3 from 5.1 into
> 5.2-RC1.

That type of hack is never recommended.  If you need libutil.so.3, I
think you would be better off to get libutil.so.3 (from a 5.1
installation).  Don't just pretend that libutil.so.4 is libutil.so.3.
You clearly seem to understand that different library version numbers
will have incompatible interfaces.

> 
> More serious seems the following problem: Sometimes when sending Email
> from Evolution built on 5.1, running on 5.2-RC1, Evolution crashes
> with an undefined reference from libc_r:
> 
> /usr/libexec/ld-elf.so.1: /usr/X11R6/lib/evolution/1.4/libeutil.so.0:
> Undefined symbol "gethostbyaddr_r"
> 
> Indeed gethostbyaddr_r seems to be present in libc.so on 5.1, but not
> any more in 5.2-RC1.
> 
> I thought minor number upgrades would have compatible libs?
> Do we need a compat51 package?
> 
> If libc was modified in an incompatible way, shouldn't we bump the
> version number?

The API for 5.x will not be officially frozen until 5.3, although it
should be very rare that incompatible changes are made this late in the
game.

I removed gethostbyaddr_r as well as some other bogus *_r functions that
were not actually re-entrant.  They should have never been added in the
form that they were.  My intent is to add non-bogus versions before 5.3.

Cheers,
-- 
Jacques Vidrine   NTT/Verio SME      FreeBSD UNIX       Heimdal
nectar at celabo.org jvidrine at verio.net nectar at freebsd.org nectar at kth.se