mirror of
https://github.com/privatevoid-net/nix-super.git
synced 2024-11-10 08:16:15 +02:00
Merge pull request #8315 from fricklerhandwerk/doc-system
add information on the system type string
This commit is contained in:
Robert Hensing
GitHub
commit
eca07b2a47
3 changed files with 89 additions and 43 deletions
|
|
@ -5,7 +5,14 @@ AC_CONFIG_AUX_DIR(config)
|
|||
|
||||
AC_PROG_SED
|
||||
|
||||
# Construct a Nix system name (like "i686-linux").
|
||||
# Construct a Nix system name (like "i686-linux"):
|
||||
# https://www.gnu.org/software/autoconf/manual/html_node/Canonicalizing.html#index-AC_005fCANONICAL_005fHOST-1
|
||||
# The inital value is produced by the `config/config.guess` script:
|
||||
# upstream: https://git.savannah.gnu.org/cgit/config.git/tree/config.guess
|
||||
# It has the following form, which is not documented anywhere:
|
||||
# <cpu>-<vendor>-<os>[<version>][-<abi>]
|
||||
# If `./configure` is passed any of the `--host`, `--build`, `--target` options, the value comes from `config/config.sub` instead:
|
||||
# upstream: https://git.savannah.gnu.org/cgit/config.git/tree/config.sub
|
||||
AC_CANONICAL_HOST
|
||||
AC_MSG_CHECKING([for the canonical Nix system name])
|
||||
|
||||
|
|
|
|||
|
|
@ -110,41 +110,72 @@ You can also build Nix for one of the [supported platforms](#platforms).
|
|||
|
||||
## Platforms
|
||||
|
||||
As specified in [`flake.nix`], Nix can be built for various platforms:
|
||||
|
||||
- `aarch64-linux`
|
||||
- `i686-linux`
|
||||
- `x86_64-darwin`
|
||||
- `x86_64-linux`
|
||||
Nix can be built for various platforms, as specified in [`flake.nix`]:
|
||||
|
||||
[`flake.nix`]: https://github.com/nixos/nix/blob/master/flake.nix
|
||||
|
||||
- `x86_64-linux`
|
||||
- `x86_64-darwin`
|
||||
- `i686-linux`
|
||||
- `aarch64-linux`
|
||||
- `aarch64-darwin`
|
||||
- `armv6l-linux`
|
||||
- `armv7l-linux`
|
||||
|
||||
In order to build Nix for a different platform than the one you're currently
|
||||
on, you need to have some way for your system Nix to build code for that
|
||||
platform. Common solutions include [remote builders] and [binfmt emulation]
|
||||
on, you need a way for your current Nix installation to build code for that
|
||||
platform. Common solutions include [remote builders] and [binary format emulation]
|
||||
(only supported on NixOS).
|
||||
|
||||
[remote builders]: ../advanced-topics/distributed-builds.md
|
||||
[binfmt emulation]: https://nixos.org/manual/nixos/stable/options.html#opt-boot.binfmt.emulatedSystems
|
||||
|
||||
These solutions let Nix perform builds as if you're on the native platform, so
|
||||
executing the build is as simple as
|
||||
|
||||
```console
|
||||
$ nix build .#packages.aarch64-linux.default
|
||||
```
|
||||
|
||||
for flake-enabled Nix, or
|
||||
Given such a setup, executing the build only requires selecting the respective attribute.
|
||||
For example, to compile for `aarch64-linux`:
|
||||
|
||||
```console
|
||||
$ nix-build --attr packages.aarch64-linux.default
|
||||
```
|
||||
|
||||
for classic Nix.
|
||||
or for Nix with the [`flakes`] and [`nix-command`] experimental features enabled:
|
||||
|
||||
You can use any of the other supported platforms in place of `aarch64-linux`.
|
||||
```console
|
||||
$ nix build .#packages.aarch64-linux.default
|
||||
```
|
||||
|
||||
Cross-compiled builds are available for ARMv6 and ARMv7, and Nix on unsupported platforms can be bootstrapped by adding more `crossSystems` in `flake.nix`.
|
||||
Cross-compiled builds are available for ARMv6 (`armv6l-linux`) and ARMv7 (`armv7l-linux`).
|
||||
Add more [system types](#system-type) to `crossSystems` in `flake.nix` to bootstrap Nix on unsupported platforms.
|
||||
|
||||
## System type
|
||||
|
||||
Nix uses a string with he following format to identify the *system type* or *platform* it runs on:
|
||||
|
||||
```
|
||||
<cpu>-<os>[-<abi>]
|
||||
```
|
||||
|
||||
It is set when Nix is compiled for the given system, and based on the output of [`config.guess`](https://github.com/nixos/nix/blob/master/config/config.guess) ([upstream](https://git.savannah.gnu.org/cgit/config.git/tree/config.guess)):
|
||||
|
||||
```
|
||||
<cpu>-<vendor>-<os>[<version>][-<abi>]
|
||||
```
|
||||
|
||||
When Nix is built such that `./configure` is passed any of the `--host`, `--build`, `--target` options, the value is based on the output of [`config.sub`](https://github.com/nixos/nix/blob/master/config/config.sub) ([upstream](https://git.savannah.gnu.org/cgit/config.git/tree/config.sub)):
|
||||
|
||||
```
|
||||
<cpu>-<vendor>[-<kernel>]-<os>
|
||||
```
|
||||
|
||||
For historic reasons and backward-compatibility, some CPU and OS identifiers are translated from the GNU Autotools naming convention in [`configure.ac`](https://github.com/nixos/nix/blob/master/config/config.sub) as follows:
|
||||
|
||||
| `config.guess` | Nix |
|
||||
|----------------------------|---------------------|
|
||||
| `amd64` | `x86_64` |
|
||||
| `i*86` | `i686` |
|
||||
| `arm6` | `arm6l` |
|
||||
| `arm7` | `arm7l` |
|
||||
| `linux-gnu*` | `linux` |
|
||||
| `linux-musl*` | `linux` |
|
||||
|
||||
## Compilation environments
|
||||
|
||||
|
|
|
|||
|
|
@ -193,18 +193,24 @@ public:
|
|||
Setting<std::string> thisSystem{
|
||||
this, SYSTEM, "system",
|
||||
R"(
|
||||
This option specifies the canonical Nix system name of the current
|
||||
installation, such as `i686-linux` or `x86_64-darwin`. Nix can only
|
||||
build derivations whose `system` attribute equals the value
|
||||
specified here. In general, it never makes sense to modify this
|
||||
value from its default, since you can use it to ‘lie’ about the
|
||||
platform you are building on (e.g., perform a Mac OS build on a
|
||||
Linux machine; the result would obviously be wrong). It only makes
|
||||
sense if the Nix binaries can run on multiple platforms, e.g.,
|
||||
‘universal binaries’ that run on `x86_64-linux` and `i686-linux`.
|
||||
The system type of the current Nix installation.
|
||||
Nix will only build a given [derivation](@docroot@/language/derivations.md) locally when its `system` attribute equals any of the values specified here or in [`extra-platforms`](#conf-extra-platforms).
|
||||
|
||||
It defaults to the canonical Nix system name detected by `configure`
|
||||
at build time.
|
||||
The default value is set when Nix itself is compiled for the system it will run on.
|
||||
The following system types are widely used, as [Nix is actively supported on these platforms](@docroot@/contributing/hacking.md#platforms):
|
||||
|
||||
- `x86_64-linux`
|
||||
- `x86_64-darwin`
|
||||
- `i686-linux`
|
||||
- `aarch64-linux`
|
||||
- `aarch64-darwin`
|
||||
- `armv6l-linux`
|
||||
- `armv7l-linux`
|
||||
|
||||
In general, you do not have to modify this setting.
|
||||
While you can force Nix to run a Darwin-specific `builder` executable on a Linux machine, the result would obviously be wrong.
|
||||
|
||||
This value is available in the Nix language as [`builtins.currentSystem`](@docroot@/language/builtin-constants.md#builtins-currentSystem).
|
||||
)"};
|
||||
|
||||
Setting<time_t> maxSilentTime{
|
||||
|
|
@ -670,18 +676,20 @@ public:
|
|||
getDefaultExtraPlatforms(),
|
||||
"extra-platforms",
|
||||
R"(
|
||||
Platforms other than the native one which this machine is capable of
|
||||
building for. This can be useful for supporting additional
|
||||
architectures on compatible machines: i686-linux can be built on
|
||||
x86\_64-linux machines (and the default for this setting reflects
|
||||
this); armv7 is backwards-compatible with armv6 and armv5tel; some
|
||||
aarch64 machines can also natively run 32-bit ARM code; and
|
||||
qemu-user may be used to support non-native platforms (though this
|
||||
may be slow and buggy). Most values for this are not enabled by
|
||||
default because build systems will often misdetect the target
|
||||
platform and generate incompatible code, so you may wish to
|
||||
cross-check the results of using this option against proper
|
||||
natively-built versions of your derivations.
|
||||
System types of executables that can be run on this machine.
|
||||
|
||||
Nix will only build a given [derivation](@docroot@/language/derivations.md) locally when its `system` attribute equals any of the values specified here or in the [`system` option](#conf-system).
|
||||
|
||||
Setting this can be useful to build derivations locally on compatible machines:
|
||||
- `i686-linux` executables can be run on `x86_64-linux` machines (set by default)
|
||||
- `x86_64-darwin` executables can be run on macOS `aarch64-darwin` with Rosetta 2 (set by default where applicable)
|
||||
- `armv6` and `armv5tel` executables can be run on `armv7`
|
||||
- some `aarch64` machines can also natively run 32-bit ARM code
|
||||
- `qemu-user` may be used to support non-native platforms (though this
|
||||
may be slow and buggy)
|
||||
|
||||
Build systems will usually detect the target platform to be the current physical system and therefore produce machine code incompatible with what may be intended in the derivation.
|
||||
You should design your derivation's `builder` accordingly and cross-check the results when using this option against natively-built versions of your derivation.
|
||||
)", {}, false};
|
||||
|
||||
Setting<StringSet> systemFeatures{
|
||||
|
|
|
|||
Loading…
Reference in a new issue