With recent MinGW64 ports of gcc, the attached program builds ok, but running it
results in a crash.
This happens with 4.6.3, 4.7.0, 4.7.3 and 4.8.1 (both 32-bit and 64-bit
versions); I haven't tried any other versions.
No such problem with mingw.org's gcc-4.7.0, nor with gcc-4.6.3 on Ubuntu.
(Note that building the attached demo program requires linking to libquadmath.a.)