[Bug] Errors will occour with many simultaneously build sessions

[dmedri]

At present, each build-type session works on the defined source tree, one at a time. It is the basic mode for end users, but it has a limit. If you run multiple build sessions simultaneously, with different types and settings, errors will occur.

The solution to the problem is a temporary copy of the source tree for the purpose, one per-session, to be deleted immediately afterwards. There are some downsides to choosing (see: more resources are required), but the benefits seem to outweigh them. Anyway, it still remains a feature request with low priority.