Avoid re-entrant calls to GC collector's callback #343
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It looks like the Python GC engine can call the GC callback while it's still being called (likely if the callback does significant enough work), which may, if you're unlucky enough, lead into a stack overflow Python is unable to recover from. This patch should fix it, though no empirical tests have been made. Signed-off-by: Aarni Koskela <akx@iki.fi>
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We should probably also try to avoid allocating memory in this function, such as by caching the children. That'll reduce the amount of data we lose due to this. |
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Is that worth the added complexity? Either way, maybe another issue should be made for that, and this merged so people don't have their Pythons fatally crashing... |
It'd avoid losing data on all bar the first GC, and be a little faster too. |
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It looks like the Python GC engine can call the GC callback
while it's still being called (likely if the callback does significant
enough work), which may, if you're unlucky enough, lead into a stack
overflow Python is unable to recover from.
This patch should fix it, though no empirical tests have been made.
Refs this issue comment: #322 (comment)