2 files changed, 2 insertions, 2 deletions
diff --git a/ext/json/ext/parser/parser.c b/ext/json/ext/parser/parser.c
index 592e729..4ac0c87 100644
--- a/ext/json/ext/parser/parser.c
+++ b/ext/json/ext/parser/parser.c
@@ -1608,7 +1608,7 @@ static VALUE convert_encoding(VALUE source)
                 FORCE_UTF8(source);
             }
         } else {
-            source = rb_str_conv_enc(source, NULL, rb_utf8_encoding());
+            source = rb_str_conv_enc(source, rb_enc_get(source), rb_utf8_encoding());
         }
     }
 #else
diff --git a/ext/json/ext/parser/parser.rl b/ext/json/ext/parser/parser.rl
index 2fa0cae..4fee7ed 100644
--- a/ext/json/ext/parser/parser.rl
+++ b/ext/json/ext/parser/parser.rl
@@ -592,7 +592,7 @@ static VALUE convert_encoding(VALUE source)
                 FORCE_UTF8(source);
             }
         } else {
-            source = rb_str_conv_enc(source, NULL, rb_utf8_encoding());
+            source = rb_str_conv_enc(source, rb_enc_get(source), rb_utf8_encoding());
         }
     }
 #else