I am trying to write an LLVM pass on Windows using Cygwin. When I make the project, a dll gets created in the Release/bin directory instead of a .so file in the Release/lib directory. The latter is what is shown in the LLVM document. When I try to load this dll using the -load flag, nothing happens. $opt -load ../../../Release/bin/Pass.dll -help The pass that I am trying to load isn't printed after this. How do I get this right?