Otherwise fall back to the computed argv[0].
This is expected by some applications, for example Git.
Code is adapted from Wine.
Many thanks to Stanislav Motylkov for having investigated this bug!
CORE-12931 CORE-13892 CORE-13898 CORE-14066
The cFileName member of WIN32_FIND_DATA is an array of MAX_PATH(260). Using strcpy/wcscpy with the target buffer being smaller is potentially bad. Corresponds to CID 1401198 and 1401195.