This replaces the mess of buildEnvs with a single Rust binary that
spits out a mostly-complete root filesystem for an fhsenv.
The main goal is to have includeClosures, as we want all of the
dependencies to be in the fhsenv to avoid Steam's (and others')
LD_LIBRARY_PATH shenanigans, but without 32-bit libraries leaking
into lib64 when a 64-bit package like mangohud depends on a 32-bit
version of itself.
We "fix" this by actually looking at the files and explicitly moving
32-bit stuff to $out/lib32. This could be avoided if we had recursive
Nix, or at least system info in exportReferencesGraph, but alas.
For some reason this also shrinks the fhsenvs massively, even though
there's currently no layout optimization (e.g. a package with paths
like lib/foo/{bar,baz} will produce two symlinks in the output, even
when it's more optimal to symlink lib/foo to $out/lib/foo directly).
`makeWrapper` is often used in these with `source "${makeWrapper}/nix-support/setup-hook"`
which causes `error: makeWrapper/makeShellWrapper must be in nativeBuildInputs` on cross.
In preparation for the deprecation of `stdenv.isX`.
These shorthands are not conducive to cross-compilation because they
hide the platforms.
Darwin might get cross-compilation for which the continued usage of `stdenv.isDarwin` will get in the way
One example of why this is bad and especially affects compiler packages
https://www.github.com/NixOS/nixpkgs/pull/343059
There are too many files to go through manually but a treewide should
get users thinking when they see a `hostPlatform.isX` in a place where it
doesn't make sense.
```
fd --type f "\.nix" | xargs sd --fixed-strings "stdenv.is" "stdenv.hostPlatform.is"
fd --type f "\.nix" | xargs sd --fixed-strings "stdenv'.is" "stdenv'.hostPlatform.is"
fd --type f "\.nix" | xargs sd --fixed-strings "clangStdenv.is" "clangStdenv.hostPlatform.is"
fd --type f "\.nix" | xargs sd --fixed-strings "gccStdenv.is" "gccStdenv.hostPlatform.is"
fd --type f "\.nix" | xargs sd --fixed-strings "stdenvNoCC.is" "stdenvNoCC.hostPlatform.is"
fd --type f "\.nix" | xargs sd --fixed-strings "inherit (stdenv) is" "inherit (stdenv.hostPlatform) is"
fd --type f "\.nix" | xargs sd --fixed-strings "buildStdenv.is" "buildStdenv.hostPlatform.is"
fd --type f "\.nix" | xargs sd --fixed-strings "effectiveStdenv.is" "effectiveStdenv.hostPlatform.is"
fd --type f "\.nix" | xargs sd --fixed-strings "originalStdenv.is" "originalStdenv.hostPlatform.is"
```
GStreamer searches for plugins relative to its binary's location.
However, since bd97973ce0, it uses its *real* binary location, breaking the FHS.
Fixes#311004 (tested on Heroic and Lutris too).
`multiPaths` is defined via invalid operation on `null` value for
non-multilib environments. Noticed on `notesnook` evan failure as:
nix-repl> notesnook.fhsenv.multiPaths
253| passthru = {
254| inherit args baseTargetPaths targetPaths baseMultiPaths multiPaths ldconfig;
| ^
255| };
error: attempt to call something which is not a function but null
The change makes `multiPaths` a private variable.
It's useful to be able to introspect all packages which are available
in the fhsenv. I've renamed basePkgs and baseMultiPkgs to be
consistent with the naming scheme used for the bits that were
previously public — names ending in "Pkgs" are for functions, and
names ending in "Paths" are the results of those functions.
Before the change the following command did not work:
$ nix develop -i --impure --expr 'with import <nixpkgs> { system = "i686-linux"; }; (buildFHSUserEnv { name = "t"; targetPkgs = ps: with ps; [ libmpc stdenv.cc ]; }).env'
$ ld -lmpc -o a
ld: cannot find -lmpc: No such file or directory
It is expected to work as `NIX_LDFLAGS` does contain valid values:
$ echo $NIX_LDFLAGS
-L/usr/lib -L/usr/lib32
Note that for `gcc` it does work:
$ printf "int main(){}" | gcc -x c - -lmpc -o a
It happens because `HOST` role is enabled for `cc`:
$ echo $NIX_CC_WRAPPER_TARGET_HOST_i686_unknown_linux_gnu
1
But not for `BINTOOLS`:
$ echo $NIX_BINTOOLS_WRAPPER_TARGET_HOST_i686_unknown_linux_gnu
<empty>
The change adds BINTOOLS role and fixes linking:
$ nix develop -i --impure --expr 'with import ~/nm { system = "i686-linux"; }; (buildFHSUserEnv { name = "t"; targetPkgs = ps: with ps; [ libmpc stdenv.cc ]; }).env'
$ printf "int main(){}" | gcc -x c - -lmpc -o a
$ ld -lmpc -o a
ld: warning: cannot find entry symbol _start; not setting start address
Most FHSEnv-wrapped packages in Nixpkgs wrap a x86_64-linux binary; making
multiArch unnecessary bloat closure size. Saves about 1G in anki-bin.
This makes multiArch FHSEnvs the exception rather than the rule.
