buildRustPackage: fix cross-compilation to aarch64-unknown-linux-musl #66617
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pkgs/build-support/rust/default.nix
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| @@ -86,6 +86,10 @@ in stdenv.mkDerivation (args // { | |||
| ${stdenv.lib.optionalString (stdenv.buildPlatform.config != stdenv.hostPlatform.config) '' | |||
| [target."${stdenv.hostPlatform.config}"] | |||
| "linker" = "${ccForHost}" | |||
| ${stdenv.lib.optionalString (stdenv.hostPlatform.config == "aarch64-unknown-linux-musl") '' | |||
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Does it have those symbols on any musl platform?
Otherwise we could set stdenv.hostPlatform.isMusl.
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It does have these symbols on x86_64 musl platform.
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Are you sure? I cannot find it:
$ nm -gC $(nix-build --no-out-link '<nixpkgs>' -A musl)/lib/libc.so | grep __addtf3
I ask since I also cannot find a definition in the musl source repository.
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I assumed that's the case, but at the very least I'm absolutely sure that cross-compiled x86_64-unknown-linux-musl executables work without this change. It seems that these symbols are used by LLVM for floating point arithmetic on AArch64 only.
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Would like to merge as-is on September 12 unless anyone minds otherwise (cc @matthewbauer @Mic92), verified this introduces no regressions while allowing cross to |
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Sorry I didn't see the fixes and merge earlier! |
Motivation for this change
See: rust-lang/rust#46651
musl libc for aarch64 doesn't have
__addtf3,__subtf3,__multf3symbols that Rust expects. This change allows to use statically linked in GCC for these symbols, allowing to build statically linked Rust binaries using Nixpkgs (Rust assumes that musl targets always want static linking).Things done
sandboxinnix.confon non-NixOS)nix-shell -p nix-review --run "nix-review wip"./result/bin/)nix path-info -Sbefore and after)Notify maintainers
cc @Ericson2314 @matthewbauer @Mic92