$! , errno, is supposed to be positive, so using -$! is something funny :)
All the "funny" stuff happens after the second Dump, which happens immediately after the stat. Unless the optimizer is punishing us for something that is going to happen later, I cannot explain why the failing stat did not appear to modify $!.

In reply to Re^4: Different behaviour of 'stat' function after assignment to $! (errno). by jpl
in thread Different behaviour of 'stat' function after assignment to $! (errno). by muxxum

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