http://bugs.winehq.org/show_bug.cgi?id=28422
--- Comment #8 from Alan W. Irwin irwin@beluga.phys.uvic.ca 2012-11-02 22:33:33 CDT --- You are right. That was a bad example since it used long double.
That just leaves the other evidence I have (that uses doubles rather than long doubles). This particular test case converts from ascii (the original data) to binary to ascii to binary for planetary ephemeris data. The two binary ephemeris results are identical on Linux and also on wine-1.5.16 with my patch applied. That may be because of the way the original data are formatted in ascii, but I am not sure about that. In contrast the other platforms the binary results are not identical on wine-git about 6 per cent of the time (out of millions of numbers). Although the differences are quite small (a relative difference of 2.e-16 is the maximum), I would still like to understand why. So I will continue to investigate and hopefully find a simple change to scanf.h for git-wine that gets rid of the differences just like my current patch does for wine-1.5.16.