diff --git a/lib/Projectrans/DeclarationGenerator.py b/lib/Projectrans/DeclarationGenerator.py
index 189dd80..590c947 100644
--- a/lib/Projectrans/DeclarationGenerator.py
+++ b/lib/Projectrans/DeclarationGenerator.py
@@ -253,7 +253,13 @@ class DeclarationGenerator:
         if not isinstance(node.target, ast.Name):
             return None
         var_name: str = node.target.id
-        if isinstance(node.annotation, ast.Attribute) and hasattr(node.annotation, 'attr') and node.annotation.attr == 'CDefine':
+        # CDefine 是编译期常量，不是变量：stub 里**不得**生成 external global。
+        # `define X: T = V` 会展开为注解 `T | t.CDefine`，故判据必须能识别**联合形态**——
+        # 原判据只认裸 `t.CDefine`（注解为单个 Attribute），联合注解会漏判 →
+        # stub 出现 `@X = external global i32` → 其他模块引用它时变成未定义符号（链接失败），
+        # 且会遮住跨模块 CDefine 常量回退（同名全局优先于常量）。与 _check_annotation_for_export
+        # 一样用递归判据。
+        if AnnotationContainsName(node.annotation, 'CDefine'):
             return None
         if isinstance(node.annotation, ast.Attribute) and hasattr(node.annotation, 'attr') and node.annotation.attr == 'CTypedef':
             return None
diff --git a/lib/core/Handles/HandlesExprAttr.py b/lib/core/Handles/HandlesExprAttr.py
index 0b77647..3407c93 100644
--- a/lib/core/Handles/HandlesExprAttr.py
+++ b/lib/core/Handles/HandlesExprAttr.py
@@ -2215,6 +2215,24 @@ class ExprAttrHandle(BaseHandle):
                     return ir.Constant(ir.IntType(32), val)
                 elif isinstance(val, float):
                     return ir.Constant(ir.FloatType(), val)
+        # 回退：_all_define_constants（Phase2Translator 从所有 .pyi 预提取的跨模块 CDefine，
+        # 与 _HandleNameLlvm 的裸名回退同源）。此前只覆盖裸名/from-import，**模块属性访问**
+        # （如 `win32file.STD_OUTPUT_HANDLE`）走到这里就落空 → 转去基座求值 + 字段/全局加载，
+        # 命中 stub 里那条错误的 `@STD_OUTPUT_HANDLE = external global`，最终链接期未定义符号。
+        # 与裸名路径同口径：仅当本模块没有同名全局时才用常量（避免遮蔽真正的模块全局）。
+        _mod_globals: Any = getattr(Gen, 'module', None)
+        _has_mod_global: bool = _mod_globals is not None and attr_name in getattr(_mod_globals, 'globals', {})
+        if not _has_mod_global:
+            all_dc: dict[str, Any] = getattr(Gen, '_all_define_constants', None) or getattr(self.Trans, '_all_define_constants', None) or {}
+            for key2 in (attr_name, full_path):
+                if key2 in all_dc:
+                    val2: Any = all_dc[key2]
+                    if isinstance(val2, int):
+                        if val2 > 0x7FFFFFFF or val2 < -0x80000000:
+                            return ir.Constant(ir.IntType(64), val2 & 0xFFFFFFFFFFFFFFFF)
+                        return ir.Constant(ir.IntType(32), val2)
+                    elif isinstance(val2, float):
+                        return ir.Constant(ir.FloatType(), val2)
         return None
 
     def _try_resolve_cross_module_enum(self, module_alias: str, enum_class_name: str, member_name: str) -> ir.Value | None: