diff --git a/src/emu/cpu/pdp1/tx0.c b/src/emu/cpu/pdp1/tx0.c
index 7977b3c7d6a..d7123b24aa0 100644
--- a/src/emu/cpu/pdp1/tx0.c
+++ b/src/emu/cpu/pdp1/tx0.c
@@ -11,6 +11,7 @@
 #include "cpuintrf.h"
 #include "debugger.h"
 #include "tx0.h"
+#include "deprecat.h"
 
 #define LOG 0
 #define LOG_EXTRA 0