[Bug libstdc++/66689] comp_ellint_3 and ellint_3 return garbage values

[3dw4rd at verizon dot net]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66689

--- Comment #5 from Ed Smith-Rowland <3dw4rd at verizon dot net> ---
in other news I've switched to boost to test this.