[Bug math/24622] powl function inaccurate for x86/x86_64

[agner at agner dot org]

https://sourceware.org/bugzilla/show_bug.cgi?id=24622

agner at agner dot org <agner at agner dot org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |agner at agner dot org

--- Comment #1 from agner at agner dot org <agner at agner dot org> ---
The powl function is less accurate than pow, and in some situations quite
inaccurate (both Gcc and Clang). The problem is discussed in bug
https://sourceware.org/bugzilla/show_bug.cgi?id=13881 and
https://sourceware.org/bugzilla/show_bug.cgi?id=706 , but I was told to file a
new bug report.

I have attached a simple test code.

More test case:
powl(9.4401197044207130E-01,9.0396338480980503E+03) relative error 7.9E-13

powl(9.6205229632635447E-01,9.0396338480980503E+03) relative error 5.1E-13

powl(1.0567906354279399E+00,9.0396338480980503E+03) relative error 5.7E-13

powl(9.5952957579581444E-01,-1.6994966845030955E+04) relative error 1.8E-12

powl(9.4249308583367331E-01,5.1811882606772378E+03) relative error 6.4E-13

powl(1.0537202715568794E+00,5.1811882606772378E+03) relative error 4.2E-13

-- 
You are receiving this mail because:
You are on the CC list for the bug.