Is it safe to use float as hash table keys?

Question

I need to keep pairs float,intin which the value intstores the number of occurrences of the value floatinside the model that I use for the tool that I am developing, and I was wondering if it is safe to do such things.

Ultimate accuracy should be a problem when talking floats are used for direct comparison (or as content that needs to be hashed), so I think this approach is not recommended, am I right?

Actually, the problem is that I have no other information in combination with these floats, so I just can not use anything else as a key for the hash table, but at the same time, since there will be many keys, having good performance will be enjoyable.

Perhaps the best solution is to use a binary search tree (or an even more advanced data structure) to get at least the average case of O (logn), also if the constant coefficient would be better.

Do you have any suggestions? Just to let you know that I am developing in OCaml, but I think that these considerations can be considered language agnostic

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