[Gc] Problem with GC on FreeBSD

[Petter Urkedal]

On 2012-04-22, Ivan Maidanski wrote:
> Petter -
> I'm not sure about the the correctness of the fix proposed by your. So, I put it into another branch for a while - https://github.com/ivmai/bdwgc/tree/fix-freelist-check-and-specific

Sure.

> I've split your patch into a refactoring one and the fix itself (with minor modifications like 2nd AO_load_acq -> AO_load).

AO_load seems more logical yes.  (Though, if I understand the AO
documentation right, the first AO_load_acquire should ensure ordering of
the two reads even if the latter was a regular read.)

> The alternate solution could be to call the check with the stopped world (but it seems to me not a trivial task to move the check there).

Yes, that should work, even if a thread is suspended during a
thread-local allocation.