1 files changed, 12 insertions, 4 deletions

diff --git a/parse.y b/parse.y
index 888b12c75e..f93550bacb 100644
--- a/parse.y
+++ b/parse.y
@@ -8761,10 +8761,10 @@ is_private_local_id(ID name)
 
 #define LVAR_USED ((ID)1 << (sizeof(ID) * CHAR_BIT - 1))
 
-static ID
-shadowing_lvar_gen(struct parser_params *parser, ID name)
+static int
+shadowing_lvar_0(struct parser_params *parser, ID name)
 {
-    if (is_private_local_id(name)) return name;
+    if (is_private_local_id(name)) return 1;
     if (dyna_in_block()) {
 	if (dvar_curr(name)) {
 	    yyerror("duplicated argument name");
@@ -8775,6 +8775,7 @@ shadowing_lvar_gen(struct parser_params *parser, ID name)
 	    if (lvtbl->used) {
 		vtable_add(lvtbl->used, (ID)ruby_sourceline | LVAR_USED);
 	    }
+	    return 0;
 	}
     }
     else {
@@ -8782,6 +8783,13 @@ shadowing_lvar_gen(struct parser_params *parser, ID name)
 	    yyerror("duplicated argument name");
 	}
     }
+    return 1;
+}
+
+static ID
+shadowing_lvar_gen(struct parser_params *parser, ID name)
+{
+    shadowing_lvar_0(parser, name);
     return name;
 }
 
@@ -8794,7 +8802,7 @@ new_bv_gen(struct parser_params *parser, ID name)
 		      rb_id2name(name));
 	return;
     }
-    shadowing_lvar(name);
+    if (!shadowing_lvar_0(parser, name)) return;
     dyna_var(name);
 }