[Nix-dev] Re: Another approach at parallelizing in-build jobs

[Ludovic Courtès]

Hi,

Peter Simons <simons at cryp.to> writes:

>  > As we have little means to achieve reproduceability once we have the
>  > parameters "-j" with a number greater than one in 'make' [...].
>
> I have heard this claim several times before, but so far no-one has been able
> to give any reasoning whatsoever to back it up.

Makefiles describe a DAG of build tasks.  Sometimes, the DAG that is
described doesn’t match the intended DAG.  Instead, the package just
“happens” to build correctly sequentially, with a specific ‘make’
implementation.

In such cases, building in parallel or using a different ‘make’
implementation is likely to uncover the bug.

Thanks,
Ludo’.