Broken delete_file/1 predicate on Windows

[Paulo Moura]

The implementation of the built-in predicate delete_file/1 in the Windows versions of B-Prolog 7.3 and 7.4 is broken, resulting in spurious messages when compiling Logtalk source files and preventing the "clean" compiler option of working. The B-Prolog developer is aware of the problem but no timeframe yet for fixing the problem. As a workaround, turn off the "clean" compiler flag in your settings files.