[Nix-dev] When did nix start to do negative build caching by default, and how to undo it?

[Bjørn Forsman]

On 24 April 2014 10:18, Peter Simons <simons at cryp.to> wrote:
> Hi Bjørn,
>
> maybe adding "--option build-cache-failure false" on the command line
> helps? I haven't tried it though, just a thought ...

Now that I know how to clear failed paths, here is my experience with
--option build-cache-failures (note the added 's' in
build-cache-failures, because that's what 'man nix.conf' says).

First time build (not really, but first time build after a nix-store
--clear-failed-paths '*'):

$ nix-build --option build-cache-failures false -A motion
these derivations will be built:
  /nix/store/qlrz1hbl171fb2g66sa8ll2rpyzm45y5-motion-3.2.12.drv
building path(s) `/nix/store/4f3h897a00w2grhfz5j4pgrgy5bc9b1m-motion-3.2.12'
building /nix/store/4f3h897a00w2grhfz5j4pgrgy5bc9b1m-motion-3.2.12
unpacking sources
[...]
make: *** [.depend] Error 1
builder for `/nix/store/qlrz1hbl171fb2g66sa8ll2rpyzm45y5-motion-3.2.12.drv'
failed with exit code 2
error: build of
`/nix/store/qlrz1hbl171fb2g66sa8ll2rpyzm45y5-motion-3.2.12.drv' failed


$ nix-build --option build-cache-failures false -A motion
these derivations will be built:
  /nix/store/qlrz1hbl171fb2g66sa8ll2rpyzm45y5-motion-3.2.12.drv
builder for `/nix/store/4f3h897a00w2grhfz5j4pgrgy5bc9b1m-motion-3.2.12'
failed previously (cached)
error: build of
`/nix/store/qlrz1hbl171fb2g66sa8ll2rpyzm45y5-motion-3.2.12.drv' failed


Why didn't nix honor my request to *not* do negative caching?

Best regards,
Bjørn Forsman