kernel32: GetModuleFileName returns a relative path

GetModuleFileName seems to return relative paths under some conditions.
I've done:

• open command prompt
• cd ..\bin [ into C:\ReactOS\bin ]
• kmtest_

kmtest_.exe asserts because GetModuleFileName gives it a relative path (which it must not).

This worked before. I'm guessing it might be related to changes in path functions. I'll try and regress-test it when I find the time.