Re-enable D optimization #16
Description
Now ldc2 doesn't work properly if optimization enabled, therefore it has been disabled for both dmd and ldc2 for fair results. Additional investigation is required, and probably ldc2 compiler should be fixed.
Even simple optimizations lead to fails:
"dflags-posix-ldc": ["-O1"]
Behaviour on various platforms:
- WSL: crashes always;
- MacOS: occasional crashes (first run after compilation always fails, but the next ones sometimes work);
- Windows: no problems;
- Linux (ArchLinux): no problems.