| 22 Aug 2025 |
 emily | but... is it wrong? :) | 10:57:33 |
| emily | it seems like it's accessing earlier bootstrap stages in some cases, maybe. | 10:57:50 |
 dramforever | targetPackages.stdenv is okay i think | 10:59:21 |
| dramforever | it's like the one package that's okay to get from targetPackages | 10:59:40 |
| dramforever | as of whether the mapping to ccFor* tbh idfk | 10:59:58 |
| dramforever | * as of whether the mapping to ccFor* is correct tbh idfk | 11:00:06 |
| emily | honestly I guess it's more likely one of these things
++
optional
(stdenv.hostPlatform.isLinux && !withBundledLLVM && !stdenv.targetPlatform.isFreeBSD && useLLVM)
"--push-state --as-needed -L${llvmPackages.libcxx}/lib -lc++ -lc++abi -lLLVM-${lib.versions.major llvmPackages.llvm.version} --pop-state"
++ optional (stdenv.hostPlatform.isDarwin && !withBundledLLVM) "-lc++ -lc++abi"
++ optional stdenv.hostPlatform.isFreeBSD "-rpath ${llvmPackages.libunwind}/lib"
++ optional (useLLVM && !withBundledLLVM && !stdenv.targetPlatform.isFreeBSD) [
llvmPackages.libunwind
# Hack which is used upstream https://github.com/gentoo/gentoo/blob/master/dev-lang/rust/rust-1.78.0.ebuild#L284
(runCommandLocal "libunwind-libgcc" { } ''
mkdir -p $out/lib
ln -s ${llvmPackages.libunwind}/lib/libunwind.so $out/lib/libgcc_s.so
ln -s ${llvmPackages.libunwind}/lib/libunwind.so $out/lib/libgcc_s.so.1
'')
];
| 11:08:51 |
| emily | since the hack that "fixes" it just involves overriding llvmPackages | 11:09:00 |
| emily | so leaning more towards "llvmPackages wire-up is busted", as I've observed that myself | 11:09:14 |
|  André Lima joined the room. | 15:07:26 |
|  elikoga changed their profile picture. | 17:27:46 |
| 23 Aug 2025 |
| André Lima | Any tips on cross-compiling a package out-of-tree with a compiler that's also built out-of-tree? I was looking into mkScopeWithSplicing', but I'm not sure how to use it outside of the Nixpkgs repository.
The concrete goal I'm trying to achieve is 1. compile a specific revision of LLVM that's used by Polygeist and 2. be able to use the clang compiler with the libc provided by that revision to cross-compile programs to another architecture. Any help is appreciated 🙏 | 22:37:19 |
| 24 Aug 2025 |
|  RichInOverdraft changed their display name from Richman to rich. | 04:10:44 |
 Artturin | With overlays | 12:22:57 |
| Artturin | * With a overlay | 12:23:14 |
| Artturin | Then you can use mkScopeWithSplicing because the set will be available top-level | 12:24:03 |
| Artturin | * Then you can use makeScopeWithSplicing' because the set will be available top-level | 12:24:50 |
| Artturin | You don't necessarily need a scope | 12:28:13 |
| Artturin | Use overlays and callPackage to get deps, then you don't have to do anything non-cross specific unless the package itself needs something | 12:28:39 |
| Artturin | * Use overlays and callPackage to get deps, then you don't have to do anything cross specific unless the package itself needs something | 12:28:55 |
| André Lima | That's very helpful, thanks | 12:33:44 |
| Artturin | * Define your packages in an overlay and use callPackage in the overlay to get deps, then you don't have to do anything cross specific unless the package itself needs something | 12:34:05 |
| emily | I think you can use it without an overlay if you use splice.nix right? | 12:56:45 |
| Artturin | splice.nix doesn't help with that | 12:59:48 |
| Artturin | You can get otherSplices without an overlay if you use all the different callPackages yourself | 13:00:15 |
| emily | it provides a generateSplicesForMkScope you can use with makeScopeWithSplicing' right? but I guess the problem is mixing in stuff from the main package set… | 13:00:19 |
| Artturin | generateSplicesForMkScope gets from pkgsBuildBuild and so on | 13:00:39 |
| Artturin | selfBuildBuild = lib.attrByPath (split "pkgsBuildBuild") bad pkgs;
selfBuildHost = lib.attrByPath (split "pkgsBuildHost") bad pkgs;
selfBuildTarget = lib.attrByPath (split "pkgsBuildTarget") bad pkgs;
selfHostHost = lib.attrByPath (split "pkgsHostHost") bad pkgs;
selfHostTarget = lib.attrByPath (split "pkgsHostTarget") bad pkgs;
selfTargetTarget = lib.attrByPath (split "pkgsTargetTarget") { } pkgs;
| 13:00:48 |
| emily | I really wish we could have generic builder functions for compiler scopes that can be used out-of-tree to produce correct cross results without an overlay | 13:00:50 |
| Artturin | Used like this otherSplices = generateSplicesForMkScope "xfce"; | 13:01:58 |
