Nix: NIX_BUILD_TOP not set correctly outside of nixos

[cleverca22]

https://gist.github.com/a0722abf36a1cfc5cadf8e39c356fba5

for some weird reason, if the sandbox is on, but nix cant get root, then the working dir, and the $NIX_BUILD_TOP wont agree on the directory

this results in things like runCommand being unable to follow $buildCommandPath and then complaining about you needing to set src or srcs

[Infinisil]

A user on IRC just encountered this, the error was

building '/nix/store/31yjixwkm35d6m2yqg3qdf367i06vvf0-kernel-modules.drv'...
/nix/store/95j91i5mkhfwqrscmiz49qab3l343jc7-stdenv-linux/setup: line 810: /build/env-vars: No such file or directory
created 3 symlinks in user environment
/nix/store/95j91i5mkhfwqrscmiz49qab3l343jc7-stdenv-linux/setup: line 313: pkgBuildAccumVars: readonly variable
[...]
/nix/store/95j91i5mkhfwqrscmiz49qab3l343jc7-stdenv-linux/setup: line 352: allPlatOffsets: readonly variable
/nix/store/95j91i5mkhfwqrscmiz49qab3l343jc7-stdenv-linux/setup: line 797: /build/env-vars: No such file or directory
kernel version is 4.19.78
building '/nix/store/wiq4rchmxckzkyvlz09lw6r0x7f3vp65-hwdb.bin.drv'...
/nix/store/95j91i5mkhfwqrscmiz49qab3l343jc7-stdenv-linux/setup: line 810: /build/env-vars: No such file or directory
unpacking sources
/nix/store/95j91i5mkhfwqrscmiz49qab3l343jc7-stdenv-linux/setup: line 810: /build/env-vars: No such file or directory
variable $src or $srcs should point to the source
builder for '/nix/store/wiq4rchmxckzkyvlz09lw6r0x7f3vp65-hwdb.bin.drv' failed with exit code 1
cannot build derivation '/nix/store/jdsra676zymclc25z5yjn395jxkk7dpw-etc.drv': 1 dependencies couldn't be built
building '/nix/store/d0nnk98k3haz7mj7ignqk1givcy21ard-linux-4.19.78-modules.drv'...
cannot build derivation '/nix/store/5va0q68d872ppqn3zw1w9la7hxizqrlq-nixos-system-vulcan-19.09.741.dbad7c7d59f.drv': 1 dependencies couldn't be built
error: build of '/nix/store/5va0q68d872ppqn3zw1w9la7hxizqrlq-nixos-system-vulcan-19.09.741.dbad7c7d59f.drv' failed

Logs including solution: https://logs.nix.samueldr.com/nixos/2019-10-12#1570910798-1570911855;

[matthewbauer]

Yeah this looks like a mistake I made in https://github.com/NixOS/nix/pull/3006. I think https://github.com/NixOS/nix/pull/3144 fixes this.

[bitonic]

For posterity, to work around the issue, pass --option sandbox false to the nix command you're running.

Edit: I've also now updated to nix 2.3.7 and the issue is resolved. I'm not sure what the first version containing that fix is though.

[nh2]

I'm not sure what the first version containing that fix is though.

It's fixed not in 2.3.1 but in 2.3.2; this is the commit in that release: https://github.com/NixOS/nix/commit/10bf5340ca35269153aca67ecd35f5419d0a08bc