HOST_PATH contains the path of the host package. This will include the
packages listed in buildInputs & depsHostHost. Use this to find
runtime commands that the host needs.
For instance to find the runtime version of perl,
$ PATH="$HOST_PATH" command -v perl
/nix/store/...-perl-5.28.0-aarch64-unknown-linux-android/bin/perl
This path should not be executed directly (it will break for cross
compilation). Only use it to find the location of executables that
will be run by your host system. Your build tools will, as always, be
available on the default PATH.
The line was essentially checking whether /bin/sh exists and is
executable and if that's the case, the isScript function returns
successfully.
When asking the author of this line on IRC it seems that even they can't
remember or imagine what this was supposed to be.
In summary: Whenever /bin/sh doesn't exist during a build, *any* file
given to isScript is reported as being a script even if it isn't.
This is kinda counter-intuitive and not something what somebody would
expect from a function called "isScript".
Signed-off-by: aszlig <aszlig@nix.build>
Cc: @edolstra
Not only does the suffix unnecessarily reduce sharing, but it also breaks
unpacker setup hooks (e.g. that of `unzip`) which identify interesting tarballs
using the file extension.
This also means we can get rid of the splicing hacks for fetchers.
We want `buildPackages` to be almost the same as
`buildPackages.buildPackges`, but that is only true if most packages
don't care about the target platform. The commented code however made
them all care about whether the target platform was Darwin.
The hack of using `crossConfig` to enforce stricter handling of
dependencies is replaced with a dedicated `strictDeps` for that purpose.
(Experience has shown that my punning was a terrible idea that made more
difficult and embarrising to teach teach.)
Now that is is clear, a few packages now use `strictDeps`, to fix
various bugs:
- bintools-wrapper and cc-wrapper
Note that a bunch of non-python packages use this attribute already.
Some of those are clearly unaware of the fact that this attribute does
not exists in stdenv because they define it but don't to add it to
their `bulidInputs` :)
Also note that I use `buildInputs` here and only handle regular
builds because python and haskell builders do it this way and I'm not
sure how to properly handle the cross-compilation case.
Following legacy packing conventions, `isArm` was defined just for
32-bit ARM instruction set. This is confusing to non packagers though,
because Aarch64 is an ARM instruction set.
The official ARM overview for ARMv8[1] is surprisingly not confusing,
given the overall state of affairs for ARM naming conventions, and
offers us a solution. It divides the nomenclature into three levels:
```
ISA: ARMv8 {-A, -R, -M}
/ \
Mode: Aarch32 Aarch64
| / \
Encoding: A64 A32 T32
```
At the top is the overall v8 instruction set archicture. Second are the
two modes, defined by bitwidth but differing in other semantics too, and
buttom are the encodings, (hopefully?) isomorphic if they encode the
same mode.
The 32 bit encodings are mostly backwards compatible with previous
non-Thumb and Thumb encodings, and if so we can pun the mode names to
instead mean "sets of compatable or isomorphic encodings", and then
voilà we have nice names for 32-bit and 64-bit arm instruction sets
which do not use the word ARM so as to not confused either laymen or
experienced ARM packages.
[1]: https://developer.arm.com/products/architecture/a-profile
(cherry picked from commit ba52ae5048)
Following legacy packing conventions, `isArm` was defined just for
32-bit ARM instruction set. This is confusing to non packagers though,
because Aarch64 is an ARM instruction set.
The official ARM overview for ARMv8[1] is surprisingly not confusing,
given the overall state of affairs for ARM naming conventions, and
offers us a solution. It divides the nomenclature into three levels:
```
ISA: ARMv8 {-A, -R, -M}
/ \
Mode: Aarch32 Aarch64
| / \
Encoding: A64 A32 T32
```
At the top is the overall v8 instruction set archicture. Second are the
two modes, defined by bitwidth but differing in other semantics too, and
buttom are the encodings, (hopefully?) isomorphic if they encode the
same mode.
The 32 bit encodings are mostly backwards compatible with previous
non-Thumb and Thumb encodings, and if so we can pun the mode names to
instead mean "sets of compatable or isomorphic encodings", and then
voilà we have nice names for 32-bit and 64-bit arm instruction sets
which do not use the word ARM so as to not confused either laymen or
experienced ARM packages.
[1]: https://developer.arm.com/products/architecture/a-profile
- `localSystem` is added, it strictly supercedes system
- `crossSystem`'s description mentions `localSystem` (and vice versa).
- No more weird special casing I don't even understand
TEMP
First, we need check against the host platform, not the build platform.
That's simple enough.
Second, we move away from exahustive finite case analysis (i.e.
exhaustively listing all platforms the package builds on). That only
work in a closed-world setting, where we know all platforms we might
build one. But with cross compilation, we may be building for arbitrary
platforms, So we need fancier filters. This is the closed world to open
world change.
The solution is instead of having a list of systems (strings in the form
"foo-bar"), we have a list of of systems or "patterns", i.e. attributes
that partially match the output of the parsers in `lib.systems.parse`.
The "check meta" logic treats the systems strings as an exact whitelist
just as before, but treats the patterns as a fuzzy whitelist,
intersecting the actual `hostPlatform` with the pattern and then
checking for equality. (This is done using `matchAttrs`).
The default convenience lists for `meta.platforms` are now changed to be
lists of patterns (usually a single pattern) in
`lib/systems/for-meta.nix` for maximum flexibility under this new
system.
Fixes#30902
This is a temporary workaround to make `nix-env -qa` and `nix search` ignore
broken packages as they they did before this patchset.
This patch should be reverted after `nix` gets a proper fix for this.
See NixOS/nix#1771.
This option makes `meta.evaluate` into a close approximation of the result of
evaluating `.outPath` by checking all the dependencies recursively at a cost of
2x slowdown. Note that actually evaluating `.outPath` costs some
5x-7x more because `.outPath` also computes all the hashes.
I hope this will be a temporary measure. If there is consensus around
issue #33599, then we can follow an explicit `dontCheck`, but default to
not checking during cross builds when none is given.
This pushes check-meta evaluation to derivation evaluation step, leaving all other
attributes accessible.
Before this commit:
> $ HOME=/homeless-shelter NIX_PATH=nixpkgs=$(pwd) nix-instantiate --eval --strict ./default.nix -A xen --argstr system aarch64-linux
> Package ‘xen-4.5.5’ in pkgs/applications/virtualization/xen/generic.nix:226 is not supported on ‘aarch64-linux’, refusing to evaluate.
as expected
> $ HOME=/homeless-shelter NIX_PATH=nixpkgs=$(pwd) nix-instantiate --eval --strict ./default.nix -A xen.name --argstr system aarch64-linux
> Package ‘xen-4.5.5’ in pkgs/applications/virtualization/xen/generic.nix:226 is not supported on ‘aarch64-linux’, refusing to evaluate.
> $ HOME=/homeless-shelter NIX_PATH=nixpkgs=$(pwd) nix-instantiate --eval --strict ./default.nix -A xen.meta.description --argstr system aarch64-linux
> Package ‘xen-4.5.5’ in pkgs/applications/virtualization/xen/generic.nix:226 is not supported on ‘aarch64-linux’, refusing to evaluate.
which is unfortunate since its impossible to use packages in autogenerated
documentation on all platforms.
After this commit:
> $ HOME=/homeless-shelter NIX_PATH=nixpkgs=$(pwd) nix-instantiate --eval --strict ./default.nix -A xen --argstr system aarch64-linux
still fails
> $ HOME=/homeless-shelter NIX_PATH=nixpkgs=$(pwd) nix-instantiate --eval --strict ./default.nix -A xen.name --argstr system aarch64-linux
> "xen-4.5.5"
> $ HOME=/homeless-shelter NIX_PATH=nixpkgs=$(pwd) nix-instantiate --eval --strict ./default.nix -A xen.meta.description --argstr system aarch64-linux
> "Xen hypervisor and related components (vanilla)"
- All deps go on the PATH
- CC and Bintools wrappers with their host != depender's host still get their
setup hooks run.
- Environment hooks get applied to all packages
This isn't so elegent, but eases the transition on a very significant
PR.
We now have the information to properly determine the role the
cc-wrapper dependency has, by taking advantage of `offset`. No longer
use the soon-to-be-deprecated crossConfig environment variable, the
temp hack used before this change.
4 far-reaching changes: Smaller PATH, New vars, different propagation
logic, and different hook logic
Smaller PATH
------------
`buildInputs` no longer go on the PATH at build time, as they cannot be
run when cross compiling and we don't want to special case. Simply make
a `nativeBuildInput` too if one needs them on the PATH. Fixes#21191.
Many new depedendency variables
-------------------------------
See the stdenv chapter of the nixpkgs manual. I pulled out the existing
documentation of dependency specification into a new section, and added
language for these two (and their propagated equivalents) along side
the others'.
More complex propagation logic
------------------------------
Before a propagated*XXX*Input always acted as if it was specified
directly as a *XXX*Input downstream. That's simple enough, but violates
the intended roles of each sort of dep, which has functional and not
just stylistic consequences.
The new algorithm is detailed in the manual, and ensures everything
ends up in the right place. I tried to give both an informal and formal
description, but I suspect in practice it will not make much sense
until one tries cross compiling, after which it will immediately make
sense as the only sane option.
Simplified hook logic
---------------------
Rather than `envHook` and `crossEnvHook`, whose behavior differs
depending on whether we are cross compiling or not, there is now one
hook per sort (or rather non-propagated and propagated pair of sorts)
of dependency. These new hooks have the same meaning regardless of
cross compilation. See the setup hook section of stdenv chapter of the
Nixpkgs manual for more details.
- tracing seems annoying enough
- we get errors for all packages instead of aborting on the first one
- easier to differentiate from unwanted packages (broken, unfree, etc.)
This continues #23374, which always kept around both attributes, by
always including both propagated files: `propgated-native-build-inputs`
and `propagated-build-inputs`. `nativePkgs` and `crossPkgs` are still
defined as before, however, so this change should only barely
observable.
This is an incremental step to fully keeping the dependencies separate
in all cases.
I find the separation of concerns, accumulating, then processing, easier
to follow. Also, with my yet-to-be-merged cross work, the accumulation
part will become more complex.
This requires some small changes in the stdenv, then working around the
weird choice LLVM made to hardcode @rpath in its install name, and then
lets us remove a ton of annoying workaround hacks in many of our Go
packages. With any luck this will mean less hackery going forward.
Why 6? It seems a decently high number, giving us room for more degrees
of debugging before the `set -x` sledgehammer without incurring a
mass-rebuild.
Environment variable filter in substituteAll was not precise and produced
undefined and invalid variable names. Vladimír Čunát tried to fix that in [1],
but `env -0` did not work during Darwin bootstrap, so [2] reverted this change
and replaced an error due to invalid variables with a warning. Recently in #28057
John Ericson added `set -u` to `setup.sh` and undefined variables made the setup
fail during e.g. `nix-build -A gnat` with `setup: line 519: !varName: unbound
variable`.
[1] 62fc8859c1
[2] 81df035429
This becomes necessary if more wrappers besides cc-wrapper start
supporting hardening flags. Also good to make the warning into an
error.
Also ensure interface is being used right: Not as a string, not just in
bash.
Older bash version, like those in the bootstrap tools and on macOS,
currently confuse variables defined as an empty array with undefined
variables. `${foo+"${foo[@]}"}` will prevent `set -u` problems with
empty arrays and older without making a single '' in the empty case.
Care is taken to `set +u` when running hooks so as to not break existing
packages.
This reverts commit eeabf85780.
This change suddenly makes tons of stdenv internals visible in
nativeBuildInputs of every derivation, which doesn't seem desirable.
E.g:
````
nix-repl> hello.nativeBuildInputs
[ «derivation /nix/store/bcfkyf6bhssxd2vzwgzmsbn7b5b9rpxc-patchelf-0.9.drv»
«derivation /nix/store/4wnshnz9wwanpfzcrdd76rri7pyqn9sk-paxctl-0.9.drv»
<< snip 10+ lines >>
«derivation /nix/store/d35pgh1lcg5nm0x28d899pxj30b8c9b2-gcc-wrapper-6.4.0.drv»
]
````
Additionally, instead of pulling them from `setup.sh`, route them via
Nix. This gets us one step closer to making stdenv be a plain attribute
set instead of a derivation.
Currently the logic of generating nixpkgs Hydra jobs is to walk through
the pkgs evaluated for system = "x86_64-linux", collect any derivations
and their meta.platforms values. However, that doesn't work for
packages whose meta.platforms doesn't include x86_64-linux, as just
evaluating their meta attribute raises an error so they get skipped
completely.
As a less-intrusive fix (i.e. anything than rewriting the current package
enumeration logic), allow passing `config.allowUnsupportedSystem = true`
to permit evaluating packages regardless of their platform and use that
in the package listing phase.
Fixes#25200
@vcunat and others rightly point out that it's easier to quote always,
than learn Bash's idiosyncrasies enough to know when it doesn't make a
difference.
This reverts commit 2743078f66, which
removes quotes that don't do anything, and then goes further adding
even more quotes.
It's better than the eval solution this is adding back, but until we can
rely on a particular version of bash in nix-shell, this just breaks too
much stuff.
See c94f3d5575
and https://github.com/NixOS/nix/pull/1483 for the better long-term
solution.
As @oxij points out in [1], this breakage is especially serious because
it changes the contents of built environments without a corresonding
change in their hashes. Also, the revert is easier than I thought.
This reverts commit 3cb745d5a6.
[1]: https://github.com/NixOS/nixpkgs/pull/27427#issuecomment-317293040
`nix-build pkgs/top-level/release.nix -A tarball` now succeeds.
`configureFlags = null` lead to a type error, and one overrideDrv
needed to be converted to to append a configureFlags list instead of
string due to the normalization.
Thanks @vcunat for alerting me to the issues---sorry I did not catch
them before merging my own PR.
Eventually the adapter will be removed. Moved is
- Name suffix from hostPlatform
- configurePlatforms
To not cause more breakage, the default is currently [], but
eventually it will be [ "build" "host" ], as the cross adapter makes
it today.
I took some liberties with the flags-echoing code to make it more
concise and correct. Also, a few warnings in findInputs and friends I
skipped because I am going to rewrite those anyways.
Thanks @grahamc for telling me about this great linter!
This makes those files a bit easier to read. Also, for what it's worth,
it brings us one baby step closer to handling spaces in store paths.
Also, I optimized handling of many transitive deps with read. Probably,
not very beneficial, but nice to enforce the pkg-per-line structure.
Doing so let me find much dubious code and fix it.
Two misc notes:
- `propagated-user-env-packages` also needed to be adjusted as
sometimes it is copied to/from the propagated input files.
- `local fd` should ensure that file descriptors aren't clobbered
during recursion.
Only cosmetic changes are done otherwise.
Real refactoring is left for later.
There's a small slow-down on my machine:
$ time nix-env -qa -P >/dev/null
gets from ~2.8 to ~3.5 seconds (negligible change in RAM).
That's most likely caused by sharing less computation between different
mkDerivation calls, and I plan to improve that soon.
This is a bit simpler now, but more importantly it scales better when I
double the number of sorts of dependencies as part of my cross
compilation work.
This is especially useful when not cross compiling. It means we can
remove the `stdenv.isGlibc` predicate too.
Additionally, use this to simplify the logic to choose the
appropriate libiconv derivation.
When not cross compiling, nativeBuildInputs and buildInputs have
identical behaviour. Currently that is implemented by having
mkDerivation do a concatenation of those variables in Nix code and pass
that to the builder via the nativeBuildInputs attribute.
However, that has some annoying side effects, like `foo.buildInputs`
evaluating to `[ ]` even if buildInputs were specified in the nix
expression for foo.
Instead, pass buildInputs and nativeBuildInputs in separate variables as
usual, and move the logic of cross compilation vs. native compilation to
the stdenv builder script. This is probably a tiny bit uglier but
fixes the previous problem.
Issue #4855.
If a package's meta has `knownVulnerabilities`, like so:
stdenv.mkDerivation {
name = "foobar-1.2.3";
...
meta.knownVulnerabilities = [
"CVE-0000-00000: remote code execution"
"CVE-0000-00001: local privilege escalation"
];
}
and a user attempts to install the package, they will be greeted with
a warning indicating that maybe they don't want to install it:
error: Package ‘foobar-1.2.3’ in ‘...default.nix:20’ is marked as insecure, refusing to evaluate.
Known issues:
- CVE-0000-00000: remote code execution
- CVE-0000-00001: local privilege escalation
You can install it anyway by whitelisting this package, using the
following methods:
a) for `nixos-rebuild` you can add ‘foobar-1.2.3’ to
`nixpkgs.config.permittedInsecurePackages` in the configuration.nix,
like so:
{
nixpkgs.config.permittedInsecurePackages = [
"foobar-1.2.3"
];
}
b) For `nix-env`, `nix-build`, `nix-shell` or any other Nix command you can add
‘foobar-1.2.3’ to `permittedInsecurePackages` in
~/.config/nixpkgs/config.nix, like so:
{
permittedInsecurePackages = [
"foobar-1.2.3"
];
}
Adding either of these configurations will permit this specific
version to be installed. A third option also exists:
NIXPKGS_ALLOW_INSECURE=1 nix-build ...
though I specifically avoided having a global file-based toggle to
disable this check. This way, users don't disable it once in order to
get a single package, and then don't realize future packages are
insecure.
If a package's meta has `knownVulnerabilities`, like so:
stdenv.mkDerivation {
name = "foobar-1.2.3";
...
meta.knownVulnerabilities = [
"CVE-0000-00000: remote code execution"
"CVE-0000-00001: local privilege escalation"
];
}
and a user attempts to install the package, they will be greeted with
a warning indicating that maybe they don't want to install it:
error: Package ‘foobar-1.2.3’ in ‘...default.nix:20’ is marked as insecure, refusing to evaluate.
Known issues:
- CVE-0000-00000: remote code execution
- CVE-0000-00001: local privilege escalation
You can install it anyway by whitelisting this package, using the
following methods:
a) for `nixos-rebuild` you can add ‘foobar-1.2.3’ to
`nixpkgs.config.permittedInsecurePackages` in the configuration.nix,
like so:
{
nixpkgs.config.permittedInsecurePackages = [
"foobar-1.2.3"
];
}
b) For `nix-env`, `nix-build`, `nix-shell` or any other Nix command you can add
‘foobar-1.2.3’ to `permittedInsecurePackages` in
~/.config/nixpkgs/config.nix, like so:
{
permittedInsecurePackages = [
"foobar-1.2.3"
];
}
Adding either of these configurations will permit this specific
version to be installed. A third option also exists:
NIXPKGS_ALLOW_INSECURE=1 nix-build ...
though I specifically avoided having a global file-based toggle to
disable this check. This way, users don't disable it once in order to
get a single package, and then don't realize future packages are
insecure.
[N.B., this package also applies to the commits that follow it in the same
PR.]
In most cases, buildPackages = pkgs so things work just as before. For
cross compiling, however, buildPackages is resolved as the previous
bootstrapping stage. This allows us to avoid the mkDerivation hacks cross
compiling currently uses today.
To avoid a massive refactor, callPackage will splice together both package
sets. Again to avoid churn, it uses the old `nativeDrv` vs `crossDrv` to do
so. So now, whether cross compiling or not, packages with get a `nativeDrv`
and `crossDrv`---in the non-cross-compiling case they are simply the same
derivation. This is good because it reduces the divergence between the
cross and non-cross dataflow. See `pkgs/top-level/splice.nix` for a comment
along the lines of the preceding paragraph, and the code that does this
splicing.
Also, `forceNativeDrv` is replaced with `forceNativePackages`. The latter
resolves `pkgs` unless the host platform is different from the build
platform, in which case it resolves to `buildPackages`. Note that the
target platform is not important here---it will not prevent
`forcedNativePackages` from resolving to `pkgs`.
--------
Temporarily, we make preserve some dubious decisions in the name of preserving
hashes:
Most importantly, we don't distinguish between "host" and "target" in the
autoconf sense. This leads to the proliferation of *Cross derivations
currently used. What we ought to is resolve native deps of the cross "build
packages" (build = host != target) package set against the "vanilla
packages" (build = host = target) package set. Instead, "build packages"
uses itself, with (informally) target != build in all cases.
This is wrong because it violates the "sliding window" principle of
bootstrapping stages that shifting the platform triple of one stage to the
left coincides with the next stage's platform triple. Only because we don't
explicitly distinguish between "host" and "target" does it appear that the
"sliding window" principle is preserved--indeed it is over the reductionary
"platform double" of just "build" and "host/target".
Additionally, we build libc, libgcc, etc in the same stage as the compilers
themselves, which is wrong because they are used at runtime, not build
time. Fixing this is somewhat subtle, and the solution and problem will be
better explained in the commit that does fix it.
Commits after this will solve both these issues, at the expense of breaking
cross hashes. Native hashes won't be broken, thankfully.
--------
Did the temporary ugliness pan out? Of the packages that currently build in
`release-cross.nix`, the only ones that have their hash changed are
`*.gcc.crossDrv` and `bootstrapTools.*.coreutilsMinimal`. In both cases I
think it doesn't matter.
1. GCC when doing a `build = host = target = foreign` build (maximally
cross), still defines environment variables like `CPATH`[1] with
packages. This seems assuredly wrong because whether gcc dynamically
links those, or the programs built by gcc dynamically link those---I
have no idea which case is reality---they should be foreign. Therefore,
in all likelihood, I just made the gcc less broken.
2. Coreutils (ab)used the old cross-compiling infrastructure to depend on
a native version of itself. When coreutils was overwritten to be built
with fewer features, the native version it used would also be
overwritten because the binding was tight. Now it uses the much looser
`BuildPackages.coreutils` which is just fine as a richer build dep
doesn't cause any problems and avoids a rebuild.
So, in conclusion I'd say the conservatism payed off. Onward to actually
raking the muck in the next PR!
[1]: https://gcc.gnu.org/onlinedocs/gcc/Environment-Variables.html
