diff --git a/py/compile.c b/py/compile.c
index 2aa98506d1..4bbdf9a95a 100644
--- a/py/compile.c
+++ b/py/compile.c
@@ -23,7 +23,7 @@
 
 typedef enum {
     PN_none = 0,
-#define DEF_RULE(rule, comp, kind, arg...) PN_##rule,
+#define DEF_RULE(rule, comp, kind, ...) PN_##rule,
 #include "grammar.h"
 #undef DEF_RULE
     PN_maximum_number_of,
diff --git a/py/parse.c b/py/parse.c
index 4288c74ccf..3cf909d752 100644
--- a/py/parse.c
+++ b/py/parse.c
@@ -40,7 +40,7 @@ typedef struct _rule_t {
 
 enum {
     RULE_none = 0,
-#define DEF_RULE(rule, comp, kind, arg...) RULE_##rule,
+#define DEF_RULE(rule, comp, kind, ...) RULE_##rule,
 #include "grammar.h"
 #undef DEF_RULE
     RULE_maximum_number_of,
@@ -56,9 +56,9 @@ enum {
 #define opt_tok(t)              (RULE_ARG_OPT_TOK | MP_TOKEN_##t)
 #define opt_rule(r)             (RULE_ARG_OPT_RULE | RULE_##r)
 #ifdef USE_RULE_NAME
-#define DEF_RULE(rule, comp, kind, arg...) static const rule_t rule_##rule = { RULE_##rule, kind, #rule, { arg } };
+#define DEF_RULE(rule, comp, kind, ...) static const rule_t rule_##rule = { RULE_##rule, kind, #rule, { __VA_ARGS__ } };
 #else
-#define DEF_RULE(rule, comp, kind, arg...) static const rule_t rule_##rule = { RULE_##rule, kind, { arg } };
+#define DEF_RULE(rule, comp, kind, ...) static const rule_t rule_##rule = { RULE_##rule, kind, { __VA_ARGS__ } };
 #endif
 #include "grammar.h"
 #undef or
@@ -74,7 +74,7 @@ enum {
 
 static const rule_t *rules[] = {
     NULL,
-#define DEF_RULE(rule, comp, kind, arg...) &rule_##rule,
+#define DEF_RULE(rule, comp, kind, ...) &rule_##rule,
 #include "grammar.h"
 #undef DEF_RULE
 };