Re: V8.0rc1 On AIX. - Mailing list pgsql-hackers

On Dec 14, 2004, at 12:51 PM, Bruce Momjian wrote:

> Peter Eisentraut wrote:
>> Bruce Momjian wrote:
>>> Huh, isn't this port testing?  Do we not want to fix port bugs at
>>> this stage?
>>
>> We are not really fixing anything, because it was never expected to 
>> work
>> before.  We are adding new functionality.  It is, of course, a
>> borderline case.  But for example, do we have any information about
>> whether what is being implemented actually works?  I don't want to 
>> find
>> out in two weeks, that yes, we managed to compile with thread support,
>> but no, threaded applications still have issues on that platform.
>
> I assume threads are supposed to work on all platforms that support it.
> We have new threading detection code in 8.0 so I expected some
> adjustments.  Also, someone pointed out that the problem was reported
> during beta but I missed it.
>
> As far as testing we have to have the users do any testing.  The thread
> testing script already tests threading but the actual compile success 
> is
> what we are adjusting now.

And that failure was, as I understand it, to accommodate using 
/usr/bin/cc because as I mentioned in my port report on an AIX 5.1 
system, /usr/bin/cc_r already works as-is.

I believe that cc_r just adds -DTHREAD_SAFETY, adds -lpthead, sets a 
LIBPATH such that /usr/lib/threads preceeds /usr/lib/ so you pick up a 
thread-safe libc.a (which you don't even necessarily need unless you 
are assuming some libc functions are thread-safe -- if you are doing 
higher-level sync yourself, then that might not even be necessary), and 
cc_r does whatever other default defines, etc are best for a safe 
multithreaded compilation.  As I recall, it used to just be a 
shell-script wrapper in AIX 4 days.

Now, on my AIX 5.1 system, /usr/bin/ cc and cc_r are both just symlinks 
back to /usr/vac/bin/xlc.  The different program names just invoke the 
different settings.  Brad:  can you make such a symlink and compile 
with that?, for example:
/home/u/brad/cc_r -> /usr/bin/xlc
./configure CC=/home/u/brad/cc_r ....

Certainly, pthreads do generally work on AIX.  I've been using them for 
years.  However, I always use cc_r (or xlC_r) for multithreaded apps.  
Peter has a point that the patch makes it compile, but does it make all 
necessary adjustments such that everything will always work?  I can't 
answer that.

-Travis