[fixed]COpenGLDriver.cpp:86:30:

[alexzk]

COpenGLDriver.cpp:86:30: error: cannot convert 'const char*' to 'const fschar_t* {aka const wchar_t*}' in initialization

This error is shown when unicode names file system is enabled (//#define _IRR_WCHAR_FILESYSTEM). Compiling by gcc 4.7 under Windows.

[hybrid]

Do you mean mingw or native gcc under Windows? This problem is due to a wrong implementation of the __TEXT define or some otherwise missing define. Seems the define exists, but is either doing nothing, or is wrongly configured. Could you please check where the __TEXT define is found in your system include files, and how it is implemented?

[CuteAlien]

Fixed it in svn trunk r4322. Or at least it compiles - unicode and mingw combination might not yet be tested so well. Note that you have to set the define UNICODE as well.
Thanks for reporting.