allow in-memory coercion of differently-named floats with same bits

For example, this allows passing a `*c_longdouble` where a `*f80` is
expected, provided that `c_longdouble` maps to `f80` for this target.
6fde2fcd51Andrew Kelley committed on 5/8/2022, 8:05:16 PMparent663b677
3 files changedLine totals unavailable