diff --git a/includes/llvmlite/__module.vp b/includes/llvmlite/__module.vp
index 0ba5cff..39ed6e3 100644
--- a/includes/llvmlite/__module.vp
+++ b/includes/llvmlite/__module.vp
@@ -7,7 +7,7 @@ import viperlib
 import memhub
 from linkedlist import GSList, GSListNode
 from .__types import LLVMType, TypePrint, Array, PrintStructDefinition, get_struct_name, Struct, ParamNode
-from .__function import Function, FunctionPrint, _ll_name_needs_quote, Param
+from .__function import Function, FunctionPrint, _ll_name_needs_quote, Param, param_get_next, param_get_ty
 
 
 # ============================================================
@@ -239,15 +239,25 @@ class LLVMModule:
                 if func_scan.Params is not None:
                     param_scan: Param | t.CPtr = func_scan.Params.Head
                     param_scan_steps: t.CSizeT = 0
+                    if param_scan is not None:
+                        # 诊断（builtins.vp dump 卡死根因排查）：对比访问器与
+                        # 直接字段访问的 param0/next——stub 字段访问若生成错误
+                        # GEP 会读到垃圾导致死循环。
+                        stdio.printf("[DIAG] param_scan 首节点: param=%llu next=%llu（函数名=%s）\n",
+                                     t.CUInt64T(param_scan), t.CUInt64T(param_scan.Next), func_scan.Name)
                     while param_scan is not None:
                         param_scan_steps += 1
                         if param_scan_steps > IR_DUMP_CHAIN_LIMIT:
-                            stdio.printf("[IR-DUMP] 链表异常: func params（函数名=%s，Params.Count=%zu，遍历超 %d 步，终止）\n",
-                                         func_scan.Name, func_scan.Params.Count, IR_DUMP_CHAIN_LIMIT)
+                            stdio.printf("[IR-DUMP] 链表异常: func params（函数名=%s，Params.Count=%zu，param=%llu next=%llu，遍历超 %d 步，终止）\n",
+                                         func_scan.Name, func_scan.Params.Count,
+                                         t.CUInt64T(param_scan), t.CUInt64T(param_scan.Next), IR_DUMP_CHAIN_LIMIT)
                             stdlib.exit(1)
-                        if param_scan.Ty is not None:
-                            self.ensure_opaque_for_type(pool, param_scan.Ty)
-                        param_scan = param_scan.Next
+                        # 用访问器（__function.vp 完整类型内）绕开 stub 字段访问
+                        # 陷阱：跨模块 struct 字段访问可能生成错误 GEP/静默跳过，
+                        # 导致 param_scan 永不更新死循环。
+                        if param_get_ty(param_scan) is not None:
+                            self.ensure_opaque_for_type(pool, param_get_ty(param_scan))
+                        param_scan = param_get_next(param_scan)
                 func_scan = func_scan.Next
             nt: NamedTypeNode | t.CPtr = self.NamedTypeHead
             # 结构体定义缓冲区：48 字段 × ~50 字节/字段类型名 ≈ 2400 字节，4096 足够