Hi, Attached is a patch that is useful (but not essential) for Windows FFI to work slightly better. Hugs builds up a command line that it passes to the compiler, for example: gcc -blah1 <filename> -blah2 In certain compilers -blah2 would not apply to <filename>, as a result when compiling with MSVC, the use of blah2 after <filename> generates a warning, but still works. The simple solution is the attached patch which moves -blah2 before <filename>. Does this harm gcc? If not then its probably a useful patch. If yes, then I'll get over it. There are a few other patches required for FFI - since the command line used by Hugs in the tree hasn't worked with visual studio compilers for a long time - I'll commit some patches tonight. With these tweaks, ffihugs works just great with windows. The only thing potentially missing is a warning that your carefully written C file is about to be trashed by ffihugs if you do the "obvious" thing. Or perhaps hugs should use a different name for the file generates, like test.temp.hugs.c ? Just anything thats less likely to clash. Thanks Neil