diff --git a/Mac/tclmods/tclMacNotify.c b/Mac/tclmods/tclMacNotify.c
index 140dadb8bbe..8fc313aee25 100644
--- a/Mac/tclmods/tclMacNotify.c
+++ b/Mac/tclmods/tclMacNotify.c
@@ -13,6 +13,10 @@
  * SCCS: @(#) tclMacNotify.c 1.36 97/05/07 19:09:29
  */
 
+#ifdef USE_GUSI
+/* Move this include up otherwise tclPort.h tried to redefine signals */
+#include <sys/signal.h>
+#endif
 #include "tclInt.h"
 #include "tclPort.h"
 #include "tclMac.h"
diff --git a/Mac/tclmods/tclSelectNotify.c b/Mac/tclmods/tclSelectNotify.c
index ea35fc62365..a728442fc15 100644
--- a/Mac/tclmods/tclSelectNotify.c
+++ b/Mac/tclmods/tclSelectNotify.c
@@ -23,6 +23,10 @@
 	#pragma import reset
 #endif
 
+#ifdef USE_GUSI
+/* Move this include up otherwise tclPort.h tried to redefine signals */
+#include <sys/signal.h>
+#endif
 #include "tclInt.h"
 #include "tclPort.h"
 #include <signal.h>