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by jepler 3373 days ago
Yes, though I'm specifically talking about when you decide to define a 'bool less_than(double, double)' that uses some kind of fuzzy comparison approach internally. This can affect any platform, not just one with the "bug #323" behavior in it.
1 comments

You don't need (and shouldn't do) any kind of fuzzy comparison for less than for floats.
You sure might imagine you need to. For instance, suppose you want to average pieces of data that are timestamped "almost the same", but could arrive to be processed with varying delays, including out of order arrival (so you can't just say "is this datum at 'about the same time as' the datum received just prior"). There are better approaches, but the one I inherited involved using a std::map which used a fuzzy less than as the ordering predicate; and my main task was to diagnose why, once in a blue moon, a segmentation fault could occur when doing some operation on the map (insertion, I think).
It seems more logical to pre-quantise the timestamps before insertion. (Actual solution I've seen practiced)