This seems to be a bit too strict now, as it is failing on aarch64, ppc64le, and s390x, where the result is 0.50096339.

Also, on my 64-bit AMD system, which is apparently using np.float128 for np.longdouble (though I don't know if that means 80-bit internally), it seems to return 0.5 exactly, which seems the opposite of the comment.

Originally posted by @QuLogic in #21634 (comment)