glibcLocales: support building on musl (#141971)

pkgs/development/libraries/glibc/common.nix

···
 , profilingLibraries ? false
 , withGd ? false
 , meta
+, extraBuildInputs ? []
+, extraNativeBuildInputs ? []
 , ...
 } @ args:
 
···
   outputs = [ "out" "bin" "dev" "static" ];
 
   depsBuildBuild = [ buildPackages.stdenv.cc ];
-  nativeBuildInputs = [ bison python3Minimal ];
-  buildInputs = [ linuxHeaders ] ++ lib.optionals withGd [ gd libpng ];
+  nativeBuildInputs = [ bison python3Minimal ] ++ extraNativeBuildInputs;
+  buildInputs = [ linuxHeaders ] ++ lib.optionals withGd [ gd libpng ] ++ extraBuildInputs;
 
   # Needed to install share/zoneinfo/zone.tab.  Set to impure /bin/sh to
   # prevent a retained dependency on the bootstrap tools in the stdenv-linux

pkgs/development/libraries/glibc/locales.nix

···
    https://sourceware.org/git/?p=glibc.git;a=blob;f=localedata/SUPPORTED
 */
 
-{ lib, stdenv, buildPackages, callPackage, writeText
+{ lib, stdenv, buildPackages, callPackage, writeText, glibc
 , allLocales ? true, locales ? [ "en_US.UTF-8/UTF-8" ]
 }:
 
···
 
   outputs = [ "out" ];
 
+  extraNativeBuildInputs = [ glibc ];
+
   # Awful hack: `localedef' doesn't allow the path to `locale-archive'
   # to be overriden, but you *can* specify a prefix, i.e. it will use
   # <prefix>/<path-to-glibc>/lib/locale/locale-archive.  So we use
···
   # $TMPDIR/nix/store/...-glibc-.../lib/locale/locale-archive.
   buildPhase =
     ''
-      mkdir -p $TMPDIR/"${buildPackages.stdenv.cc.libc.out}/lib/locale"
+      mkdir -p $TMPDIR/"${buildPackages.glibc.out}/lib/locale"
 
       echo 'C.UTF-8/UTF-8 \' >> ../glibc-2*/localedata/SUPPORTED
 

pkgs/top-level/all-packages.nix

···
 
   relibc = callPackage ../development/libraries/relibc { };
 
-  # Only supported on Linux, using glibc
-  glibcLocales = if stdenv.hostPlatform.libc == "glibc" then callPackage ../development/libraries/glibc/locales.nix { } else null;
+  # Only supported on Linux
+  glibcLocales = if stdenv.hostPlatform.isLinux then callPackage ../development/libraries/glibc/locales.nix { } else null;
 
   glibcInfo = callPackage ../development/libraries/glibc/info.nix { };