diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index cea7a7478ad..15be2dcacbf 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -1556,7 +1556,6 @@ with pkgs;
     m17n = callPackage ../tools/inputmethods/ibus-engines/ibus-m17n { };
 
     mozc = callPackage ../tools/inputmethods/ibus-engines/ibus-mozc rec {
-      clangStdenv = libcxxStdenv; # workaround for https://github.com/NixOS/nixpkgs/issues/28223
       python = python2;
       inherit (python2Packages) gyp;
       protobuf = pkgs.protobuf.overrideDerivation (oldAttrs: { stdenv = clangStdenv; });
@@ -2043,7 +2042,6 @@ with pkgs;
     m17n = callPackage ../tools/inputmethods/fcitx-engines/fcitx-m17n { };
 
     mozc = callPackage ../tools/inputmethods/fcitx-engines/fcitx-mozc rec {
-      clangStdenv = libcxxStdenv; # workaround for https://github.com/NixOS/nixpkgs/issues/28223
       python = python2;
       inherit (python2Packages) gyp;
       protobuf = pkgs.protobuf.overrideDerivation (oldAttrs: { stdenv = clangStdenv; });