In the interaction between FFI, GC, and hash tables, so yes, in the FFI itself, not in particular bindings: https://github.com/racket/racket/issues/2702 https:

In the interaction between FFI, GC, and hash tables, so yes, in the FFI itself, not in particular bindings: https://github.com/racket/racket/issues/2702 https://github.com/racket/racket/issues/2702 https://github.com/racket/racket/issues/2263 https://github.com/racket/racket/issues/2263 There were workarounds (in Racket you can instruct the GC not to move your FFI objects) and I believe the underlying issues have been fixed. I must add that I got immediate and comprehensive support from the core developers, who not only fixed the bug but also suggested the workaround (so I could continue to support all our target versions of Racket).