diff --git a/src/array.c b/src/array.c
index 2103eac24..e902d5ba7 100644
--- a/src/array.c
+++ b/src/array.c
@@ -543,15 +543,15 @@ mrb_ary_push_m(mrb_state *mrb, mrb_value self)
   mrb_int len, len2;
   struct RArray *a;
 
-  argc = mrb_get_argc(mrb);
-  argv = mrb_get_argv(mrb);
-  a = mrb_ary_ptr(self);
   ary_modify(mrb, a);
+  argc = mrb_get_argc(mrb);
+  a = mrb_ary_ptr(self);
   len = ARY_LEN(a);
   len2 = len + argc;
   if (ARY_CAPA(a) < len2) {
     ary_expand_capa(mrb, a, len2);
   }
+  argv = mrb_get_argv(mrb);
   array_copy(ARY_PTR(a)+len, argv, argc);
   ARY_SET_LEN(a, len2);
   while (argc--) {