diff --git a/pkgs/build-support/cc-wrapper/default.nix b/pkgs/build-support/cc-wrapper/default.nix
index 0b25d70b14a2b..57a090b1976c2 100644
--- a/pkgs/build-support/cc-wrapper/default.nix
+++ b/pkgs/build-support/cc-wrapper/default.nix
@@ -551,10 +551,10 @@ stdenv.mkDerivation {
     # additional -isystem flags will confuse gfortran (see
     # https://github.com/NixOS/nixpkgs/pull/209870#issuecomment-1500550903)
     + optionalString (libcxx == null && isClang && (useGccForLibs && gccForLibs.langCC or false)) ''
-      for dir in ${gccForLibs}${lib.optionalString (hostPlatform != targetPlatform) "/${targetPlatform.config}"}/include/c++/*; do
+      for dir in ${gccForLibs}/include/c++/*; do
         echo "-isystem $dir" >> $out/nix-support/libcxx-cxxflags
       done
-      for dir in ${gccForLibs}${lib.optionalString (hostPlatform != targetPlatform) "/${targetPlatform.config}"}/include/c++/*/${targetPlatform.config}; do
+      for dir in ${gccForLibs}/include/c++/*/${targetPlatform.config}; do
         echo "-isystem $dir" >> $out/nix-support/libcxx-cxxflags
       done
     ''