diff --git a/pkgs/build-support/emacs/setup-hook.sh b/pkgs/build-support/emacs/setup-hook.sh
index e1db3e828fd7..b55c18738023 100644
--- a/pkgs/build-support/emacs/setup-hook.sh
+++ b/pkgs/build-support/emacs/setup-hook.sh
@@ -1,11 +1,11 @@
 addEmacsVars () {
-  if test -d $1/share/emacs/site-lisp; then
-      export EMACSLOADPATH="$1/share/emacs/site-lisp:$EMACSLOADPATH"
+  if [[ -d "$1/share/emacs/site-lisp" ]]; then
+      export EMACSLOADPATH="$1/share/emacs/site-lisp${EMACSLOADPATH:+:}${EMACSLOADPATH-}"
   fi
 }
 
 # If this is for a wrapper derivation, emacs and the dependencies are all
 # run-time dependencies. If this is for precompiling packages into bytecode,
 # emacs is a compile-time dependency of the package.
-addEnvHooks "$targetOffset" addEmacsVars
+addEnvHooks "$hostOffset" addEmacsVars
 addEnvHooks "$targetOffset" addEmacsVars