I getting
```
import/core/sync/mutex.d(87,36): Error: `pthread_mutexattr_init`
cannot be interpreted at compile time, because it has no
available source code
```
compile time error. One of those D exceptions which doesn't say
where it happened in your code so you need to comment out the
lines that might cause it one by one :D
I found that this was caused by the "FileLogger" which I create
at the top of the file. But why?
```d
import std.experimental.logger: FileLogger;
auto fileLogger = new FileLogger("last.log");
```
Moving the FileLogger instantiation to a function fixes the issue
though.
