diff --git a/avrdude/config_gram.y b/avrdude/config_gram.y
index f3407f66..70bc8fca 100644
--- a/avrdude/config_gram.y
+++ b/avrdude/config_gram.y
@@ -116,10 +116,13 @@ static int parse_cmdbits(OPCODE * op);
 %token TKN_STRING
 %token TKN_ID
 
-%start config
+%start configuration
 
 %%
 
+configuration :
+  /* empty */ | config
+;
 
 config :
   def |
@@ -148,9 +151,7 @@ def :
     strncpy(default_serial, $3->value.string, PATH_MAX);
     default_serial[PATH_MAX-1] = 0;
     free_token($3);
-  } |
-
-  /* empty */
+  }
 ;