Thanks, eXpl0i3r! That put an end to the error and now it spits out the executable.
However, the program crashes immediately when I start it up. The crash seems to stem from sfml-window-2.dll. I included the built SFML DLLs (sfml-graphics-2.dll, sfml-window-2.dll, etc) into the same folder as the executable so it has access to those things.