diff --git a/Python/marshal.c b/Python/marshal.c
index 7b12ab7..22ca49c 100644
--- a/Python/marshal.c
+++ b/Python/marshal.c
@@ -1105,6 +1105,7 @@
 
     case TYPE_ASCII_INTERNED:
         is_interned = 1;
+        /* fall through */
     case TYPE_ASCII:
         n = r_long(p);
         if (PyErr_Occurred())
@@ -1117,6 +1118,7 @@
 
     case TYPE_SHORT_ASCII_INTERNED:
         is_interned = 1;
+        /* fall through */
     case TYPE_SHORT_ASCII:
         n = r_byte(p);
         if (n == EOF) {
@@ -1142,6 +1144,7 @@
 
     case TYPE_INTERNED:
         is_interned = 1;
+        /* fall through */
     case TYPE_UNICODE:
         {
         const char *buffer;