Q: Why do I get C816-gcc.exe error in Windows 10 ?

A: There is a conflict between GCC3 and Cygwin in Windows10.
RKit-C816 has been tested on Windows10 and works fine with GCC4 (which doesn't use Cygwin).

To avoid the crash you must upgrade to GCC4 compiler.

You must also check (even with GCC4) that there is no conflicting cygwin dll (cygwin1.dll usually) in your Windows PATH, that might have been installed by other some software. (or by an older version of the C816 tools)