A second take at eb28e5e72e, which was reverted for the extra logging
during the internals of `nix-shell -p`. This commit does the same
logging, but to $NIX_LOG_FD instead, which is echoed during any normal
build, but not during the internals of `nix-shell -p`.
[1]: eb28e5e72e
This is a small simplification of the control flow surrounding these cases. It should make it more obvious when each case happens, and also explicitly defines the current behaviour of --replace.
Provide a `runPhase` function which wraps the phase running action of
genericBuild. The new function can be used as an interface by `nix
develop`, i.e. `nix develop some#flake --build` may just call `runPhase
build`, which makes its behavior more consistent with `nix build`.
In preparation of fixing https://github.com/NixOS/nix/issues/6202
Relying on `.attrs.sh` to exist in `$NIX_BUILD_TOP` is problematic
because that's not compatible with how `nix-shell(1)` behaves. It places
`.attrs.{json,sh}` into a temporary directory and makes them accessible via
`$NIX_ATTRS_{SH,JSON}_FILE` in the environment[1]. The sole reason that
`nix-shell(1)` still works with structured-attrs enabled derivations
is that the contents of `.attrs.sh` are sourced into the
shell before sourcing `$stdenv/setup` (if `$stdenv` exists) by `nix-shell`.
However, the assumption that two files called `.attrs.sh` and
`.attrs.json` exist in `$NIX_BUILD_TOP` is wrong in an interactive shell
session and thus an inconsistency between shell debug session and actual
builds which can lead to unexpected problems.
To be precise, we currently have the following problem: an expression
like
with import ./. {};
runCommand "foo" { __structuredAttrs = true; foo.bar = [ 1 2 3 ]; }
''
echo "''${__structuredAttrs@Q}"
touch $out
''
prints `1` in its build-log. However when building interactively in a
`nix-shell`, it doesn't.
Because of that, I'm considering to propose a full deprecation of
`$NIX_BUILD_TOP/.attrs.{json,sh}`. A first step is to only mention the
environment variables, but not the actual paths anymore in Nix's
manual[2]. The second step - this patch - is to fix nixpkgs' stdenv
accordingly.
Please note that we cannot check for `-e "$NIX_ATTRS_JSON_FILE"` because
certain outdated Nix minors (that are still in the range of supported
Nix versions in `nixpkgs`) have a bug where `NIX_ATTRS_JSON_FILE` points
to the wrong file while building[3].
Also, for compatibility with Nix 2.3 which doesn't provide these
environment variables at all we still need to check for the existence of
.attrs.json/.attrs.sh here. As soon as we bump nixpkgs' minver to 2.4,
this can be dropped.
Finally, dropped the check for ATTRS_SH_FILE because that was never
relevant. In nix#4770 the ATTRS_SH_FILE variable was introduced[4] and
in a review iteration prefixed with NIX_[5]. In other words, these
variables were never part of a release and you'd only have this problem
if you'd use a Nix from a git revision of my branch from back then. In
other words, that's dead code.
[1] https://github.com/nixos/nix/pull/4770#issuecomment-834718851
[2] https://github.com/NixOS/nix/pull/9032
[3] https://github.com/NixOS/nix/issues/6736
[4] 3944a120ec
[5] 27ce722638
In the default `fixupPhase` the output of `substituteAllStream` is
streamed to setup-hook.
`stdenv.cc.bintools.overrideAttrs { NIX_DEBUG = 6; }`
With `NIX_DEBUG` contains:
```
@expandResponseParams@ -> /nix/store/yl01rd58vp4m8bbhkihpk132cprfmx6f-expand-response-params/bin/expand-response-params
...
```
The NIX_LIB64|32_IN_SELF_RPATH environment variables control whether
to add lib64 and lib32 to rpaths. However, they're set depending
on the build paltform, not the target platform and thus their values
are incorrect for for cross-builds.
On the other hand, setting them according to the build platform introduce
pointless differences in build outputs; see #221350 for details.
This change fixes the issues by boldly removes the NIX_LIB*_IN_SELF_RPATH
facility altogether, in the hope that it is no longer necessary. They
were introduced in 2009, long before nixpkgs had good support for
cross-builds.
Fixes#221350
The primary motivating example is openssl:
Before the change full package build took 1m54s minutes.
After the change full package build takes 59s.
About a 2x speedup.
The difference is visible because openssl builds hundreds of manpages
spawning a perl process per manual in `install` phase. Such a workload
is very easy to parallelize.
Another example would be `autotools`+`libtool` based build system where
install step requires relinking. The more binaries there are to relink
the more gain it will be to do it in parallel.
The change enables parallel installs by default only for buiilds that
already have parallel builds enabled. There is a high chance those build
systems already handle parallelism well but some packages will fail.
Consistently propagated the enableParallelBuilding to:
- cmake (enabled by default, similar to builds)
- ninja (set parallelism explicitly, don't rely on default)
- bmake (enable when requested)
- scons (enable when requested)
- meson (set parallelism explicitly, don't rely on default)
- waf (set parallelism explicitly, don't rely on default)
- qmake-4/5/6 (enable by default, similar to builds)
- xorg (always enable, similar to builds)
Some other packages, for example ruby gems via buildRubyGem, use a
variable called "type" internally, which is overwritten here and
causes failures like:
failure: $gempkg path unspecified
Fix for changes in 11c3127e38.
this is intentional to support both structuredAttrs and non
In pkgs/stdenv/generic/setup.sh line 614:
for pkg in ${depsBuildBuild[@]} ${depsBuildBuildPropagated[@]}; do
^------------------^ SC2068 (error): Double quote array expansions to avoid re-splitting elements.
In pkgs/stdenv/generic/setup.sh line 521:
local varRef="$varVar[$((targetOffset - hostOffset))]"
^-- SC1087 (error): Use braces when expanding arrays, e.g. ${array[idx]} (or ${var}[.. to quiet).
exit -1 == exit 255 but we don't have a reason to use 255
In pkgs/stdenv/generic/setup.sh line 518:
(( hostOffset <= targetOffset )) || exit -1
^-- SC2242 (error): Can only exit with status 0-255. Other data should be wri
tten to stdout/stderr.
we use [*] to support structuredAttrs and non
In pkgs/stdenv/generic/setup.sh line 1542:
for curPhase in ${phases[*]}; do
^----------^ SC2048 (warning): Use "${array[@]}" (with quotes) to prevent whitespace problems.
In pkgs/stdenv/generic/setup.sh line 101:
source "$hookName"
^---------^ SC1090 (warning): ShellCheck can't follow non-constant source. Use a directive to specify location.
In pkgs/stdenv/generic/setup.sh line 166:
mkdir -p "$out/nix-support"
^--^ SC2154 (warning): out is referenced but not assigned.
In pkgs/stdenv/generic/setup.sh line 407:
PATH=
^--^ SC2123 (warning): PATH is the shell search path. Use another name.
In pkgs/stdenv/generic/setup.sh line 452:
declare -a pkgBuildAccumVars=(pkgsBuildBuild pkgsBuildHost pkgsBuildTarget)
^---------------^ SC2034 (warning): pkgBuildAccumVars appears unused. Verify use (or export if used e
xternally).
because pkgBuildAccumVars is used
In pkgs/stdenv/generic/setup.sh line 235:
nameref="$* ${nameref-}"
^-----^ SC2178 (warning): Variable was used as an array but is now assigned a string.
because we theres a useArray conditional
In pkgs/stdenv/generic/setup.sh line 36:
: ${outputs:=out}
^-------------^ SC2223 (info): This default assignment may cause DoS due to globbing. Quote it.
otherwise the build just fails with 'make: *** No rule to make target 'install'. Stop.'
and update buildPhase message
i don't know if the 'makefile may have been created in buildPhase' is
true but i guess it might be possible
Derivations not using `__structuredAttrs` should not attempt to set
environment variables from `env`.
Derivations using `__structuredAttrs` should fail if `env` is not
exportable.
Co-authored-by: Robin Gloster <mail@glob.in>
stdenv: print message if structuredAttrs is enabled
stdenv: add _append
reduces the chance of a user doing it wrong
fix nix develop issue
output hooks don't work yet in nix develop though
making $outputs be the same on non-structuredAttrs and structuredAttrs
is too much trouble.
lets instead make a function that gets the output names
reading environment file '/nix/store/2x7m69a2sm2kh0r6v0q5s9z1dh41m4xf-xz-5.2.5-env-bin'
nix: src/nix/develop.cc:299: std::string Common::makeRcScript(nix::ref<nix::Store>, const BuildEnvironment&, const Path&): Assertion `outputs != buildEnvironment.vars.end()' failed.
use a function to get all output names instead of using $outputs
copy env functionality from https://github.com/NixOS/nixpkgs/pull/76732/commits
Passing `-l$NIX_BUILD_CORES` improperly limits the overall system load.
For a build machine which is configured to run `$B` builds where each
build gets `total cores / B` cores (`$C`), passing `-l $C` to make will
improperly limit the load to `$C` instead of `$B * $C`.
This effect becomes quite pronounced on machines with 80 cores, with
40 simultaneous builds and a cores limit of 2. On a machine with this
configuration, Nix will run 40 builds and make will limit the overall
system load to approximately 2. A build machine with this many cores
can happily run with a load approaching 80.
A non-solution is to oversubscribe the machine, by picking a larger
`$C`. However, there is no way to divide the number of cores in a way
which fairly subdivides the available cores when `$B` is greater than
1.
There has been exploration of passing a jobserver in to the sandbox,
or sharing a jobserver between all the builds. This is one option, but
relatively complicated and only supports make. Lots of other software
uses its own implementation of `-j` and doesn't support either `-l` or
the Make jobserver.
For the case of an interactive user machine, the user should limit
overall system load using `$B`, `$C`, and optionally systemd's
cpu/network/io limiting features.
Making this change should significantly improve the utilization of our
build farm, and improve the throughput of Hydra.
inherit_errexit wasn’t available in bash 3. We have a check to show a
nice error message, but that check is after we set inherit_errexit in
setup.sh. So we can just move this to below the BASH_VERSINFO check.
