diff --git a/build.py b/build.py
index b084a7c..8eb9e71 100644
--- a/build.py
+++ b/build.py
@@ -9,6 +9,7 @@ import threading
 clean = '--noclean' not in sys.argv
 kernel_only = '--kernel-only' in sys.argv
 noapp = '--noapp' in sys.argv
+bootloader = '--bootloader' in sys.argv
 
 
 # 编译内核
@@ -97,6 +98,20 @@ else:
         shutil.copy(vpui_path, "./disk/libs/vpui64.so")
 
 
+# 编译 bootloader（GNU-EFI：MSYS make → WSL Ubuntu）；
+# bootx64.efi 不由 viperc 产出，容易忘记重编而一直用旧引导器（改了 boot.c / 内核预留逻辑
+# 却仍在用旧件）。显式传 --bootloader 才重编；未传时若 boot.c 比产物新则给出提醒。
+boot_src = "boot/boot.c"
+boot_out = "disk/EFI/BOOT/bootx64.efi"
+if bootloader:
+    print("[build] building bootloader (make -C boot)...")
+    boot_rc = os.system('make -C boot')
+    if boot_rc != 0:
+        print("[build] 警告: bootloader 构建失败（需 MSYS make + WSL Ubuntu + _UNCADK/tools/gnu-efi）")
+elif os.path.exists(boot_src) and os.path.exists(boot_out) and os.path.getmtime(boot_src) > os.path.getmtime(boot_out):
+    print("[build] 警告: boot/boot.c 比 disk/EFI/BOOT/bootx64.efi 新 → bootloader 已过期，请用 --bootloader 重编")
+
+
 os.system('powershell -ExecutionPolicy Bypass -File ./Scripts/disk.ps1')