Can't run nofib in parallel

I was under the impression that make -j$n within nofib would run benchmarks in parallel, but it doesn't. The following warning is indicative:

make[1]: warning: -jN forced in submake: disabling jobserver mode.

Whenever make is called recursively, any -j flags will lead to this warning and consequently disable parallelisation (which would lead to a number of jobs exponential in the depth of recursive calls).

Parallel benchmarks are useful to get deterministic metrics such as allocations or counted instructions really fast.

Trac metadata

Trac field	Value
Version
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	NoFib benchmark suite
Test case
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