I always did find it rather peculiar that one of the suggested actions for resolving compile errors was to reduce the length of the file path.

Finally someone found the cause of that, thank you! Debugging didn't really help find the reason of the problem with paths, I'm not sure why I didn't look into Scanner.l myself. But I had to replace snprintf with sprintf because snprintf was not recognized by VS 2013 compiler.

I found the issue because VS 2015 reported a stack overrun in Ecc for certain *.es files in my build - that's why I also switched it to use the safer snprintf. I think all versions of VS have _snprintf instead but apparently that works slightly different than the standard snprintf. Anyway, in this case a buffer size of 512 with sprintf is more than enough for Windows (which enforces a max path length of 260 on every file) and should also suffice for other platforms.