| 25 May 2025 |
 Tristan Ross | Then we could overlay that and it hopefully wouldn't have to eval stages before the new stages. | 15:44:26 |
 Randy Eckenrode | I’d prefer to view the stdenv bootstrap as a black box so that implementation details don’t become fixed API. | 15:47:48 |
| Tristan Ross | True though we'd have to do something to the stdenv for it to be able to do cross unless we split CC away from the stdenv. | 15:48:47 |
| Randy Eckenrode | Darwin’s stdenv bootstrap has changed a lot. The SDK update dropped several stages last fall. | 15:49:04 |
| Randy Eckenrode | I wish the stdenv bootstrap could be structured like a cross from bootstrap tools to final environment. | 15:49:17 |
| Randy Eckenrode | Let the standard cross-compilation machinery take care of building things for the right platforms instead of having to micromanage a bunch of overrides. | 15:49:38 |
| Randy Eckenrode | Then from there you could cross to another platform. | 15:49:53 |
| Randy Eckenrode | I wonder if some of the hard-coded stuff could be removed. Right now, stdenvNoCC is an override of stdenv. Could it be the other way? stdenv is stdenvNoCC with the requisite compilers as extra packages? | 15:51:19 |
| Tristan Ross | Yeah, that's what I'm thinking | 15:51:36 |
| Randy Eckenrode | IIRC wasn’t there some talk about that for libc++ once libstdc++ gets split out of gcc? | 15:51:42 |
| Tristan Ross | Idk but probably | 15:52:01 |
| Tristan Ross | It would be nice to be able to view the stdenv as just tools and CC as the actual C toolchain | 15:52:42 |
| Tristan Ross | And you could override the unwinder, cxxlib, etc | 15:53:00 |
| Tristan Ross | I think I've seen clang get rebuilt for cross so being able to not have to rebuild clang when doing cross would be nice | 15:54:05 |
| Randy Eckenrode | Clang shouldn’t be rebuilt for cross anymore. Only the wrapper now. | 16:44:06 |
| Randy Eckenrode | Darwin bintools shouldn’t need rebuilding either, but that work hadn’t been done yet. | 16:45:14 |
| Tristan Ross | In reply to @reckenrode:matrix.org
Clang shouldn’t be rebuilt for cross anymore. Only the wrapper now. Huh, it's rebuilt for me when I tried getting it to work with crossStdenv. But I've found a problem where the bintools wrapper for LLVM doesn't include as for target lol. | 16:52:05 |
| Randy Eckenrode | Weird. There was work done early in the 25.05 cycle to reduce the Clang rebuilds. | 16:52:38 |
| Randy Eckenrode | https://github.com/NixOS/nixpkgs/pull/355532
https://github.com/NixOS/nixpkgs/pull/356162
https://github.com/NixOS/nixpkgs/pull/357633 | 16:53:28 |
| Randy Eckenrode | On Darwin, I get /nix/store/5ibsf7mwyci07f5kdxrzww43204y7ysv-clang-20.1.4.drv for every:
$ nix-instantiate . -A pkgsCross.gnu64.llvmPackages.libcxxStdenv.cc.cc
$ nix-instantiate . -A pkgsCross.gnu64.pkgsLLVM.stdenv.cc.cc
$ nix-instantiate . -A pkgsCross.x86_64-darwin.stdenv.cc.cc
$ nix-instantiate . -A stdenv.cc.cc
$ nix-instantiate . -A clang.cc
$ nix-instantiate . -A llvmPackages.clang.cc
$ nix-instantiate . -A llvmPackages_20.clang.cc
| 16:55:03 |
| Tristan Ross | Yeah, it's something which started when I made glibc actually handle cross correctly in crossStdenv | 16:57:10 |
| Tristan Ross | Which also led me to discovering that GCC with no libc to handle glibc is actually borked in crossStdenv.predicated.useLLVM.native | 16:57:59 |
| Tristan Ross | One of the things I'm thinking now is, what if we had top-level attributes which could handle some cross logic without inheritly using the top-level stdenv's targetPlatform so pkgs/top-level/cross-stdenv.nix is less of a mess | 17:00:31 |
| Tristan Ross | @[Randy Eckenrode] @[Alyssa Ross] Would you be inclined in writing a design doc with me of all the changes we need to make the stdenv and CC better? I'm hoping all the stdenv team could work together on it. | 17:23:14 |
 aleksana 🏳️⚧️ (force me to bed after 18:00 UTC) | hedgedoc time! | 17:24:15 |
 Alyssa Ross | I could possibly give feedback but for now I'm still focusing on trying to catch up with the last several weeks of GitHub notifications that accumulated while I was recovering from dental surgeru | 17:25:37 |
| Alyssa Ross | * | 17:25:40 |
| Tristan Ross | Gotcha, yeah I think these changes will span across multiple versions because it'll be quite a lot of work | 17:27:13 |
| Tristan Ross | In reply to @aleksana:mozilla.org
hedgedoc time! Is that what pad.lassul.us is lol | 17:29:34 |
| Tristan Ross | Is there someone here who could pin a message? I'm thinking it might be good to pin the link to the design doc on the new stdenv & CC improvements. | 17:36:37 |
