diff --git a/mrbgems/mruby-array-ext/src/array.c b/mrbgems/mruby-array-ext/src/array.c
index 76d8b75e6..e138bb793 100644
--- a/mrbgems/mruby-array-ext/src/array.c
+++ b/mrbgems/mruby-array-ext/src/array.c
@@ -227,7 +227,7 @@ ary_compact_bang(mrb_state *mrb, mrb_value self)
     }
   }
   if (i == j) return mrb_nil_value();
-  if (j < len) ARY_SET_LEN(RARRAY(self), j);
+  ARY_SET_LEN(RARRAY(self), j);
   return self;
 }