diff --git a/fmt-c-writer.scm b/fmt-c-writer.scm
index 869e2d7..f84d65d 100644
--- a/fmt-c-writer.scm
+++ b/fmt-c-writer.scm
@@ -141,10 +141,11 @@
   ;; * const char -> const char *
   ;; const * const char -> const char * const
   (if (atom? type) (atom-to-fmt-c type)
-      (tree-map atom-to-fmt-c
-                (fold-right append (list)
-                            (list-join (reverse (list-split type '*))
-                                       '(*))))))
+      (flatten
+       (tree-map atom-to-fmt-c
+                 (fold-right append (list)
+                             (list-join (reverse (list-split type '*))
+                                        '(*)))))))
 
 (define (walk-fn-def form)
   (match form
diff --git a/tests/fmt-c-writer.scm b/tests/fmt-c-writer.scm
index e9cf699..a9384b1 100644
--- a/tests/fmt-c-writer.scm
+++ b/tests/fmt-c-writer.scm
@@ -64,6 +64,14 @@
    '(%var (struct suc) s)
    (walk-var '(var s (struct suc))))
 
+  (test
+   '(%var (const struct suc *) s s1)
+   (walk-var '(var s (* const struct suc) s1)))
+
+  (test
+   '(%var (const struct suc *) s s1)
+   (walk-var '(var s (* (const struct suc)) s1)))
+
   (test
    '(%var (struct suc) s (hoge piyo))
    (walk-var '(var s (struct suc) (hoge piyo))))