- Use CL instead of GCC
- Use .lib and .dll instead of just .dll.a and .dll (and .so.a and .so)
- Object files are now .obj instead of .o
- Use /O2 and /Wall instead of -O2 and -Wall
- Use /Iincdir instead of -Iincdir
- I'm not sure, but probably /Llibdir instead of -Llibdir
CL.exe /O2 /Wall /Ddefine=value [sources.c] [libraries.lib]
CL.exe /O2 /Wall /D_USRDLL /D_WINDLL [sources.c] [libraries.lib] /link /DLL /OUT:dllname.dll