The bug report describes an issue where `fakeroot` under `qemu` fails with the error message `semop(1): encountered an error: Function not implemented`. This error is related to a syscall (`semop`) not being implemented correctly in `qemu`, which caused the failure. The user mentions that they are using the most recent version of `qemu` built from the git repository, implying that the issue might still exist despite previous fixes.

The problem occurs during runtime when executing `fakeroot debian/rules clean` as part of a `dpkg-buildpackage` process within an `schroot` environment. The error points to a specific syscall malfunctioning, which falls under the category of system call issues.

**Answer:**
syscall