Even good old C includes several functions that seem "redundant" at first glance [0] but are necessary for edge cases. I suppose this is similar to mechanics like fused multiply-add [1].

[0]: https://www.johndcook.com/blog/2010/06/07/math-library-funct...

[1]: https://en.wikipedia.org/wiki/Multiply%E2%80%93accumulate_op...