Why isn't cl.exe producing a valid Windows module?

Question

I have a simple C DLL that exposes functions from a static library. The DLL compiles without errors and I can run DUMPBIN on it to see the exports. However, when I attempt to load it with DllImport in C#, it says this:

System.DllNotFoundException: Unable to load DLL 'ei.dll': The specified module could not be found. (Exception from HRESULT: 0x8007007E).

It's in the correct directory, for sure. So, I read that it might be a good idea to try Dependency Walker, in case I need to include something else. Unfortunately, when I try to open my DLL in DW, I get this:

Error: At least one file was not a 32-bit or 64-bit Windows module.

Here's my cl command:

set ERL_INTERFACE_DIR=C:\Progra~1\erl5.7.2\lib\erl_interface-3.6.2\
call vcvars32.bat
cl /I%ERL_INTERFACE_DIR%include /LD ei.c ei.lib Ws2_32.lib /link /LIBPATH:%ERL_INTERFACE_DIR%lib

What could be causing this?

Answer 1

I was linking with a LIB file whose name is the same as the LIB file that the compiler emits, so it was linking with itself. I just changed the name of my source file to ErlInterface.c. I would think the linker would throw up a warning or something when this happens, but it doesn't.

Anyway, I can open the DLL in Dependency Walker now, but I still can't use it with DllImport. That's for another question, though.