But the increment doesn't happen in user code. It happens internally in the perl code, which is guaranteed to be thread safe (unless there is a bug). So this wouldn't be an issue. the issue I queried about is not, clearly, something that is internal, but is a short hand for a user-land test and then set, thus while it *could* be optimized, I sorta doubted it, but thought I'd check.

The case you are talking about would imply a bug in perl in it not being thread safe, since variable reference counts are not user-land features, but things handled automatically by perl -- so they are inherently thread-safe as much as perl is defined to be thread-safe.

That said, I'm sure you'd have to protect such increments from multi-threaded access, inside perl, but that's not something we need to worry about in userland.

In reply to Re^2: is ||= threadsafe? by perl-diddler
in thread is ||= threadsafe? by perl-diddler

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