diff --git a/elisp/latex-help.el b/elisp/latex-help.el
index c2935a4..15275d9 100644
--- a/elisp/latex-help.el
+++ b/elisp/latex-help.el
@@ -264,10 +264,10 @@ A marker file is a file that signifies that its parent is a texdoc entry."
                                (regexp-quote dirname))
                        name)))))
 
-(defun latex-help--search-texdoc-root (root)
-  "Search the texdoc root directory ROOT and discover package names."
-  (cl-loop with found = nil
-           with to-search = nil
+(defun latex-help--search-texdoc-root (root found)
+  "Search the texdoc root directory ROOT and discover package names.
+FOUND is the hash table in which to put the entries."
+  (cl-loop with to-search = nil
            for dir = root then (pop to-search)
            while dir
            when (file-directory-p dir) do
@@ -276,7 +276,7 @@ A marker file is a file that signifies that its parent is a texdoc entry."
                                  (latex-help--is-marker-file file root))
                                files)
                  ;; dir is an entry
-                 (push (file-name-nondirectory dir) found)
+                 (puthash (file-name-nondirectory dir) nil found)
                ;; search all subdirs
                (setq to-search
                      (nconc to-search
@@ -299,39 +299,38 @@ A marker file is a file that signifies that its parent is a texdoc entry."
                                           (group (+ any)) eol) nil t)
              collect (match-string 1))))
 
-(defun latex-help--texdoc-config-file-entries (file)
+(defun latex-help--texdoc-config-file-entries (file found)
   "Parse the texdoc config file FILE to find entries.
 This attempts to find entries that might have been missed during the initial
-scan.  The return value is a list of cahce entries with the second element being
-nil (signifying that we don't know the directory they below to)."
+scan.  The entries will be `puthash'ed into FOUND as keys."
   (with-temp-buffer
     (insert-file-contents file)
     (goto-char (point-min))
-    (let ((found))
-      (while (re-search-forward (rx bol "adjscore("
-                                    (group (+ (not ")"))) ")")
-                                nil t)
-        (push (match-string 1) found))
-      (while (re-search-forward
-              (rx bol "alias" (? "(" (+ (any (?0 . ?9) ".")) ")")
-                  " " (group (+ (not " ")))
-                  " = " (group (* (not (any "#" "\n" " ")))))
-              nil t)
-        (push (match-string 1) found)
-        (let ((m2 (match-string 2)))
-          (unless (or (zerop (length m2))
-                      (seq-contains-p m2 ?/))
-            (push m2 found))))
-      found)))
+    (while (re-search-forward (rx bol "adjscore("
+                                  (group (+ (not ")"))) ")")
+                              nil t)
+      (puthash (match-string 1) nil found))
+    (goto-char (point-min))
+    (while (re-search-forward
+            (rx bol "alias" (? "(" (+ (any (?0 . ?9) ".")) ")")
+                " " (group (+ (not " ")))
+                " = " (group (* (not (any "#" "\n" " ")))))
+            nil t)
+      (puthash (match-string 1) nil found)
+      (let ((m2 (match-string 2)))
+        (unless (or (zerop (length m2))
+                    (seq-contains-p m2 ?/))
+          (puthash m2 nil found))))))
 
 (defun latex-help--discover-texdoc-entries ()
   "Discover texdoc entries in each of `latex-help-documentation-roots'."
-  (let ((output))
+  (let ((found (make-hash-table :test 'equal)))
     (dolist (root latex-help-documentation-roots)
-      (setq output (nconc output (latex-help--search-texdoc-root root))))
+      (latex-help--search-texdoc-root root found))
     (dolist (file (latex-help--texdoc-config-files))
-      (setq output (nconc output (latex-help--texdoc-config-file-entries file))))
-    (seq-uniq output)))
+      (latex-help--texdoc-config-file-entries file found))
+    (cl-loop for entry being the hash-keys of found
+             collect entry)))
 
 (defun latex-help--texdoc-files-for-entry (entry)
   "List the texdoc files for ENTRY.