This changes makes nix detect a machines available cores automatically whenever build-cores is set to 0.
So far, nix simply passed NIX_BUILD_CORES=0 whenever build-cores is set to 0. (only when build-cores is unset it was detecting cores automatically)
The behavior of passing NIX_BUILD_CORES=0 leads to a performance penalty when sourcing nixpkgs' generic builder's `setup.sh`, as setup.sh has to execute `nproc`. This significantly slows down sourcing of setup.sh
If a build directory is accessible to other users it is possible to
smuggle data in and out of build directories. Usually this is only
a build purity problem, but in combination with other issues it can
be used to break out of a build sandbox. to prevent this we default
to using a subdirectory of nixStateDir (which is more restrictive).
(cherry picked from pennae Lix commit 55b416f6897fb0d8a9315a530a9b7f0914458ded)
(store setting done by roberth)
As summarized in
https://github.com/NixOS/nix/issues/77#issuecomment-2843228280 the
motivation is that the complicated retry logic this introduced was
making the cleanup task #12628 harder to accomplish. It was not easy to
ascertain just what policy / semantics the extra control-flow was
implementing, in order to figure out a different way to implementing it
either.
After talking to Eelco about it, he decided we could just....get rid of
the feature entirely! It's a bit scary removing a decade+ old feature,
but I think he is right. See the release notes for more explanation.
This reverts commit 299141ecbd.
Co-authored-by: Eelco Dolstra <edolstra@gmail.com>
Curl creates sockets without setting FD_CLOEXEC/SOCK_CLOEXEC, this can
cause connections to remain open forever when using commands like `nix
shell`
This change sets the FD_CLOEXEC flag using a CURLOPT_SOCKOPTFUNCTION
callback.
The experimental `nix eval` command already supports a `--raw` flag.
This commit implements the same flag for the stable nix-instantiate command.
Until now instructions and scripts that didn't want to rely on experimental
features had to use workarounds such as:
nix-instantiate --eval <something> | tr -d \"
(which also undesirably also removes double quotation marks within the string), or
nix-instantiate --eval <something> | jq -j
(which undesirably depends on another package).
Co-authored-by: Silvan Mosberger <silvan.mosberger@tweag.io>
