On 2017-06-04 19:14:06 -0400, Tom Lane wrote: > Andres Freund <and...@anarazel.de> writes: > > At the moment a number of flag variables set in signal handlers have > > 'volatile bool' as type, others have 'volatile sig_atomic_t'. That's > > kinda confusing. I think either is safe, but I think we should > > standardize one of them. > > sig_atomic_t is more standards-conforming, I should think. I'm not sure > if there are any current platforms where a store to a char variable > wouldn't be atomic, but why live dangerously?
Well, we already have some variables that aren't actually booleans, although I think all of them are only read not manipulated in signal handlers (InterruptHoldoffCount etc). So one could argue that there's no safety benefit in sig_atomic_t, because we're already using in other places. We also already rely on int32 stores being atomic in other parts of the code, although that's between processes not between signal / normal path of execution. > I'd be inclined to let the code continue to treat the variables as > if they were bool, ie store "true" and "false" not "1" and "0" > into them. That should be perfectly safe. Indeed. Greetings, Andres Freund -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
