[Vm-dev] [OpenSmalltalk/opensmalltalk-vm] `CompiledMethod someInstance includes: 40` segfaults reproducibly (#512)

Eliot Miranda notifications at github.com
Tue Jun 23 04:06:34 UTC 2020


Hi Fabio, thanks for this.  Investigating now.  It is throwing up three issues.

1. there's a bug in checking for forwarding pointers on primitive failure.  The first field of a cogged method can be followed, which is a no no if the method is cogged.  Hence a better test case is
    thisContext method includes: 42
because the method will always be cogged and it will always crash.
2. somehow the cog method reference gets answered as the result, which is the bug that crashes the VM.  Not found out why yet.
3. the bug is arguably an unintended consequence of CompiledMethod inheriting from ByteArray.  If it didn't then we wouldn't hit this bug.  Since it does in current images, the bug must be fixed in the VM.

-- 
You are receiving this because you are subscribed to this thread.
Reply to this email directly or view it on GitHub:
https://github.com/OpenSmalltalk/opensmalltalk-vm/issues/512#issuecomment-647894598
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.squeakfoundation.org/pipermail/vm-dev/attachments/20200622/5ad3dd40/attachment-0001.html>


More information about the Vm-dev mailing list