diff --git a/includes/ast/exprs.vp b/includes/ast/exprs.vp
index eaac740..85e54b9 100644
--- a/includes/ast/exprs.vp
+++ b/includes/ast/exprs.vp
@@ -2,6 +2,7 @@ import t, c
 from stdint import *
 import memhub
 import string
+import stdio
 from .base import (
     AST, ExprNode, ASTKind, ASTCtx, OpKind,
     _init_ast, _copy_str, _set_parent_list,
@@ -949,6 +950,10 @@ class Attribute(ExprNode):
         self.value = value
         self.attr = _copy_str(pool, attr)
         self.ctx = ctx
+        # 诊断（stdint.vp Attribute.attr 垃圾定位）：构造后打印 attr 副本地址
+        stdio.printf("[DIAG] Attribute.__init__: this=%llu attr_src=%llu attr_copy=%llu value=%llu ctx=%d\n",
+                     t.CUInt64T(self), t.CUInt64T(attr), t.CUInt64T(self.attr),
+                     t.CUInt64T(self.value), self.ctx)
 
     def kind(self) -> t.CInt:
         return ASTKind.Attribute