[ovs-dev] Building OVS on Ubuntu 12.04 stuck in atomic operation unit test

[Ben Pfaff]

On Mon, Jan 05, 2015 at 09:01:38PM +0900, Motonori Shindo wrote:
> When building OVS (the latest master) under Ubuntu 12.04, it stuck at the unit test "test atomic operations” and never finishes (or it could just be unbearably slow). This problem doesn’t happen in Ubuntu 14.04, however. 
> 
> library unit tests
> 
>  21: test flow extractor                             ok
>  22: test TCP/IP checksumming                        ok
>  23: test hash functions                             ok
>  24: test hash map                                   ok
>  25: test hash index                                 ok
>  26: test cuckoo hash                                ok
>  27: test atomic operations                          <stuck here forever>
> 
> This could be because gcc in Ubuntu 12.04 is too old that it can’t
> handle atomic operations very well. Please see more details below
> about two environments I experimented. Is this a known issue?

We've heard similar reports before but it's challenging to find the
problem.  I can't reproduce the problem on my 32-bit Debian system by
just, for example, switching to GCC 4.6.

What's in config.h and config.log?

How many cores does the system running the build have?

(It would be equally useful to have these answers from anyone
experiencing this problem.)

Thanks,

Ben.