diff --git a/sys/arch/i386/isa/icu.h b/sys/arch/i386/isa/icu.h
index 5855ab39982a..ccba88db30f4 100644
--- a/sys/arch/i386/isa/icu.h
+++ b/sys/arch/i386/isa/icu.h
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)icu.h	5.6 (Berkeley) 5/9/91
- *	$Id: icu.h,v 1.13 1994/04/07 06:50:35 mycroft Exp $
+ *	$Id: icu.h,v 1.14 1994/10/01 03:37:37 mycroft Exp $
  */
 
 /*
@@ -52,9 +52,10 @@
  */
 extern	unsigned imen;		/* interrupt mask enable */
 
-#define	INTREN(s)	do{imen &= ~(s); SET_ICUS();}while(0)
-#define	INTRDIS(s)	do{imen |= (s); SET_ICUS();}while(0)
-#define	INTRMASK(msk,s)	(msk |= (s))
+#define	INTRUNMASK(msk,s)	(msk &= ~(s))
+#define	INTREN(s)		(INTRUNMASK(imen, s), SET_ICUS())
+#define	INTRMASK(msk,s)		(msk |= (s))
+#define	INTRDIS(s)		(INTRMASK(imen, s), SET_ICUS())
 #if 0
 #define SET_ICUS()	do{outb(IO_ICU1 + 1, imen); outb(IU_ICU2 + 1, imen >> 8);}while(0)
 #else