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If it >> comes from sframe, then it should be pretty solid. However, if it comes >> from frame pointers used as a fallback on a system that omits frame >> pointers, the user should consider the resulting data with a high level >> of skepticism. > > That would be in the trace sent to the callback. We could add something > like the '?' if it's not trusted. > > But for now, until we have a use case that we are implementing, I want > to keep this simple, otherwise it will never get done. I don't want to > add features for hypothetical scenarios. > > Currently, the traceback is just an array of addresses. But this could > change in the future. What we are discussing right now is the internal > functionality of the user unwind code where I have made most of theses > functions static. > > The only external functions that get called during the iteration is the > architecture specific code. If that code needs to know the difference > between sframes and frame pointers then we can modify it, but until > then, I rather keep this as is. Indeed it's only kernel internal API, but this is API that will be expected by each architecture supporting unwind_user. Changing this later on will cause a lot of friction and cross-architecture churn compared to doing it right in the first place. Thanks, Mathieu > > Jens, is there something that the architecture code needs now? If so, > then lets fix it, otherwise lets do it when there is something. This > isn't user API, it can change in the future. > > -- Steve -- Mathieu Desnoyers EfficiOS Inc. https://www.efficios.com