[ts-gen] Shift to debian testing; and g++ 4.3.2-1 works with -O3

Bill Pippin pippin at owlriver.net
Fri Jan 2 18:18:01 EST 2009


I've recently shifted my development platform from Centos 5.2 to
Debian testing [lenny]; I've made this change primarily in order
to use a newer release of g++.  In the past, users compiling against
a newer version of g++ than was found in Centos have discovered
problems before we did, and although the stability of Centos has
certainly been convenient, I'd prefer to avoid such surprises.

Although I'd earlier used Ubuntu 8.04 as a quasi-Debian testbed
because of its popularity among other users, my primary goal here
was to use the newest non-bleeding edge g++ in widespread use, and
I feel that's best installed via Debian testing.

So, our primary development platform is now debian lenny i64.
Due to security issues, when lenny moves to stable, I'll stick
with it for a while [fall back from testing to stable], although
once the security team starts providing updates for testing
again, I intend to move back up to that distribution.

On lenny the shim compiles, starts up, and passes the regression
tests even with -O3 set for optimization via CFLAGS in the Makefile.
Lenny provides g++ 4.3.2-1, whereas ubuntu 8.04 ships g++ 4.3.2 ,
and 4.3.2-1 seems to fix the "value optimized out" problem.  In an
earlier post, I noted that the shim did not compile correctly on
ubuntu:

> ... Ubuntu 8.04 ... duplicated the problems seen by Nils.  ... it
> became clear that g++ [with -O3] had utterly ruined argument passing
> for reference parameters, with the args not only turned to garbage ---
> which could conceivably be due to some error in my code elsewhere ---
> but also for many other cases optimized away, even though they were
> clearly essential.

I'm a bit surprised that 4.3.2-1 has fixed the -O3 bug for the shim;
plenty of other C++ packages are still having problems compiling on
debian, and not just in December, but even up until yesterday.  To see
this, use the query: debian 4.3.2 "value optimized out" on google, and
look at the google groups results for linux.debian.bugs.dist .  

Nevertheless, I'm turning -O3 back on as the default for compilation.
Those running Ubuntu 8.04 (hardy heron) will need to turn it off in
the Makefile, and I'd appreciate getting reports as to whether
shim installations for Ubuntu 8.10 (intrepid ibex) work properly
with -O3 turned on.  For such reports, please include the version
of g++, i.e., the text output by "g++ --version".

Thanks,

Bill



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