Allow dereferencing a rooted Gc during collection #163
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Ordinarily, objects dropped during collections would only contain unrooted Gc pointers. But with `#[unsafe_ignore_trace]` it’s possible to smuggle a rooted Gc pointer into the heap. When we collect a rooted Gc pointer, we need to dereference it in order to unroot its contents. This should be safe because the associated allocation cannot have been collected while the Gc is rooted. Fixes an “assertion failed: finalizer_safe()” panic in the included test case (refs Manishearth#52). Signed-off-by: Anders Kaseorg <[email protected]>
Manishearth
approved these changes
Feb 5, 2023
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Ordinarily, objects dropped during collections would only contain unrooted
Gcpointers. But with#[unsafe_ignore_trace]it’s possible to smuggle a rootedGcpointer into the heap. When we collect a rootedGcpointer, we need to dereference it in order to unroot its contents. This should be safe because the associated allocation cannot have been collected while theGcis rooted.Fixes an
assertion failed: finalizer_safe()panic in the included test case (refs #52).