GC compaction causes segfaults #17
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to demonstrate that compaction breaks something between the two libraries.
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@maths22 Can you please kick off CI on this one? |
flavorjones
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I bet this explains the intermittent segfaults I was randomly getting while working on #16 this afternoon, going off the hypothesis that they only happened if GC happened to run mid-spec run. Thank you for pinning this down better than I could; between me having minimal C-extension-level ruby debugging experience and the segfault only happening occasionally and not happening in CI I was just bewildered. |
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Short-term, it may be worth telling users to make sure to avoid or disable compaction. I may not get time to look at it this week. |
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because that gem doesn't support compaction and frequently segfaults see instructure/nokogiri-xmlsec-instructure#17
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A few releases of Nokogiri on the v1.13.x branch were to fix Nokogiri when GC compaction happens in Ruby 3.0+.
Something's broken with the xmlsec integration with Nokogiri in this gem which segfaults during compaction / object relocation. I think it's because xmlsec is freeing memory that Nokogiri still has a handle on, leading to dangling pointers that cause a problem when objects are relocated during compaction.
This PR just compacts after each spec to reproduce the issue. I'm not sure how to solve it yet, I need to do a bit more work to fully understand it.