[QBS] Possible to limit number of concurrent threads to use when building?

[William Gallafent]

Hi,

When building on a computer with 4 CPUs but restricted memory (only
512MB!), I would like to limit the number of concurrent build
processes to fewer than the number of CPUs, since allowing 4 threads
to run concurrently leads to memory exhaustion. Is there a way to do
this? Grepping for "threads" in the QBS source tree didn't reveal
anything obvious!

-- 
Bill Gallafent.