--- a/t/arch.c	2021-08-03 15:35:12.952984598 +0800
+++ b/t/arch.c	2021-08-03 15:34:47.284542645 +0800
@@ -1,5 +1,5 @@
 #include "../arch/arch.h"
 
 unsigned long arch_flags = 0;
-bool tsc_reliable;
+extern bool tsc_reliable;
 int arch_random;