Re: Our "fallback" atomics implementation doesn't actually work - Mailing list pgsql-hackers

On 2016-10-05 14:01:05 -0400, Tom Lane wrote:
> I was trying to measure whether unnamed POSIX semaphores are any faster
> or slower than the SysV kind.  Plain pgbench is not very helpful for
> determining this, because we've optimized the system to the point that
> you don't hit semop waits all that often.  So I tried this:
> 
> configure USE_UNNAMED_POSIX_SEMAPHORES=1 --disable-cassert --disable-spinlocks --disable-atomics

Pretty independent from the complaint at hand, but if I just do that I get
undefined reference to symbol 'sem_post@@GLIBC_2.2.5'

I needed to add -pthread -lrt to LDFLAGS to make it work.

Andres