Build with LLVM and musl

flake.nix

@@ -95,7 +95,7 @@
     overlays = load ./overlay "overlay";
     legacyPackages = eachSystem (system: platform:
       import nixpkgs {
-        localSystem = builtins.currentSystem or platform;
+        localSystem = builtins.currentSystem or system;
         crossSystem = platform;
         overlays = [ self.overlays.default ];
         config.allowUnsupportedSystem = true;
@@ -120,6 +120,13 @@
           targetHost = config.networking.fqdnOrHostName;
           targetUser = null;
         };
+
+        nixpkgs = let
+          platform = self.lib.platforms.x86_64-linux;
+        in {
+          buildPlatform = builtins.currentSystem or platform.system;
+          hostPlatform = platform;
+        };
       };
     };
 

lib/platforms.nix

@@ -4,13 +4,25 @@ let inherit (nixpkgs) lib;
 in lib.mapAttrs (system: platform: lib.systems.elaborate platform) {
   "x86_64-linux" = {
     system = "x86_64-linux";
+    config = "x86_64-unknown-linux-musl";
+    useLLVM = true;
+    linker = "lld";
+    gcc.arch = "x86-64-v3";
   };
 
   "aarch64-linux" = {
     system = "aarch64-linux";
+    config = "aarch64-unknown-linux-musl";
+    useLLVM = true;
+    linker = "lld";
+    gcc.arch = "armv8-a";
   };
 
   "riscv64-linux" = {
     system = "riscv64-linux";
+    config = "riscv64-unknown-linux-musl";
+    useLLVM = true;
+    linker = "lld";
+    gcc.arch = "rv64imacfd";
   };
 }

nixos/module/default.nix

@@ -11,6 +11,7 @@
     iosched
     kernel
     locale-en_EU
+    musl
     network
     nix
     openssh

nixos/module/musl.nix

@@ -0,0 +1,7 @@
+{ ...}: { modulesPath, ... }: {
+  disabledModules = [
+    (modulesPath + "/config/ldso.nix")
+    (modulesPath + "/programs/nix-ld.nix")
+    (modulesPath + "/config/stub-ld.nix")
+  ];
+}

overlay/fixes.nix

@@ -4,6 +4,14 @@ let
   inherit (lib) toList;
   inherit (prev.stdenv) hostPlatform;
 in {
+  netbsd = prev.netbsd.overrideScope (final: prev: {
+    compatIfNeeded = [ final.compat ];
+
+    compat = prev.compat.overrideAttrs (prevAttrs: {
+      makeFlags = prevAttrs.makeFlags ++ [ "OBJCOPY=:" ];
+    });
+  });
+
   numactl = prev.numactl.overrideAttrs (prevAttrs: {
     patches = prevAttrs.patches or [ ] ++ [
       (final.fetchpatch {
@@ -13,19 +21,21 @@ in {
     ];
   });
 
+  python3 = prev.python3.overrideAttrs (prevAttrs: {
+    postFixup = let
+      lib = "$out/lib/${prevAttrs.passthru.libPrefix}";
+      prefix = "_sysconfigdata__linux_";
+      suffix = "${hostPlatform.parsed.cpu.name}-${hostPlatform.libc}";
+    in prevAttrs.postFixup + ''
+      test -e '${lib}/${prefix}${suffix}.py' \
+        || ln -s '${lib}/${prefix}'{,'${suffix}'}.py
+    '';
+  });
+
   redis = prev.redis.overrideAttrs {
     doCheck = false;
   };
 
-  python312 = prev.python312.override {
-    packageOverrides = final: prev: {
-      pywebview = prev.pywebview.overrideAttrs ({
-        doCheck = false;
-        doInstallCheck = false;
-      });
-    };
-  };
-
   sioyek = prev.sioyek.overrideAttrs (prevAttrs: {
     env = prevAttrs.env or { } // {
       NIX_CFLAGS_COMPILE = toList prevAttrs.env.NIX_CFLAGS_COMPILE or [ ]
@@ -33,6 +43,14 @@ in {
     };
   });
 
+  time = prev.time.overrideAttrs (prevAttrs: {
+    env = prevAttrs.env or { } // {
+      CFLAGS = toList prevAttrs.env.CFLAGS or [ ] ++ [
+        "-Wno-error=implicit-function-declaration"
+      ] |> toString;
+    };
+  });
+
   zeromq = prev.zeromq.overrideAttrs (prevAttrs: {
     postPatch = prevAttrs.postPatch or "" + ''
       substituteInPlace CMakeLists.txt \