diff --git a/lib/nghttp2_http.c b/lib/nghttp2_http.c
index d75615aa..9ad07767 100644
--- a/lib/nghttp2_http.c
+++ b/lib/nghttp2_http.c
@@ -69,8 +69,10 @@ typedef enum {
   NGHTTP2_TOKEN_MAXIDX,
 } nghttp2_token;
 
-// This function was generated by genlibtokenlookup.py.  Inspired by
-// h2o header lookup.  https://github.com/h2o/h2o
+/*
+ * This function was generated by genlibtokenlookup.py.  Inspired by
+ * h2o header lookup.  https://github.com/h2o/h2o
+ */
 static int lookup_token(const uint8_t *name, size_t namelen) {
   switch (namelen) {
   case 2: