1 files changed, 1 insertions, 1 deletions

diff --git a/src/font.h b/src/font.h
index 9285330ce54..2db8d35af48 100644
--- a/src/font.h
+++ b/src/font.h
@@ -545,7 +545,7 @@ struct font_driver
   Lisp_Object (*open) (struct frame *f, Lisp_Object font_entity,
                        int pixel_size);
 
-  /* Close FONT.  */
+  /* Close FONT.  NOTE: this can be called by GC.  */
   void (*close) (struct font *font);
 
   /* Optional (if FACE->extra is not used).