--- bochs-2.8/instrument/stubs/instrument.cc.orig	2024-03-10 07:59:37.000000000 +0100
+++ bochs-2.8/instrument/stubs/instrument.cc	2024-03-26 20:47:30.140134418 +0100
@@ -24,6 +24,8 @@
 
 #if BX_INSTRUMENTATION
 
+class bxInstruction_c;
+
 void bx_instr_init_env(void) {}
 void bx_instr_exit_env(void) {}