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A-incr-compArea: incremental compilationArea: incremental compilationC-enhancementCategory: enhancementCategory: enhancementE-help-wantedCall for participation: extra help is wantedCall for participation: extra help is wantedE-mediumDifficulty: might require some prior knowledge or code readingDifficulty: might require some prior knowledge or code readingE-needs-writeupCall for participation: discussion can be written up without much research requiredCall for participation: discussion can be written up without much research requiredT-compilerRelevant to compiler teamRelevant to compiler team
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So rustc is full of these impl_stable_hash_for
. What are these for? I originally thought that would be for FxHashMap
, but that seems to be wrong (I still need to derive(Hash)
to use FxHashMap
). So now I am just confused. It would be great if the guide could explain that.
@eddyb said "incremental" but that on its own does not explain much of anything -- why is Hash
not good enough? Why do I need a tcx
to compute a "stable hash"?
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A-incr-compArea: incremental compilationArea: incremental compilationC-enhancementCategory: enhancementCategory: enhancementE-help-wantedCall for participation: extra help is wantedCall for participation: extra help is wantedE-mediumDifficulty: might require some prior knowledge or code readingDifficulty: might require some prior knowledge or code readingE-needs-writeupCall for participation: discussion can be written up without much research requiredCall for participation: discussion can be written up without much research requiredT-compilerRelevant to compiler teamRelevant to compiler team