diff --git a/engine/common/mathlib.h b/engine/common/mathlib.h
index ac6ec0e15..be5e46540 100644
--- a/engine/common/mathlib.h
+++ b/engine/common/mathlib.h
@@ -45,10 +45,10 @@ extern	int nanmask;
 #define	IS_NAN(x) (((*(int *)&x)&nanmask)==nanmask)
 
 #define DotProduct(x,y) (x[0]*y[0]+x[1]*y[1]+x[2]*y[2])
-#define VectorSubtract(a,b,c) {c[0]=a[0]-b[0];c[1]=a[1]-b[1];c[2]=a[2]-b[2];}
-#define VectorAdd(a,b,c) {c[0]=a[0]+b[0];c[1]=a[1]+b[1];c[2]=a[2]+b[2];}
+#define VectorSubtract(a,b,c) {(c)[0]=(a)[0]-(b)[0];(c)[1]=(a)[1]-(b)[1];(c)[2]=(a)[2]-(b)[2];}
+#define VectorAdd(a,b,c) {(c)[0]=(a)[0]+(b)[0];(c)[1]=(a)[1]+(b)[1];(c)[2]=(a)[2]+(b)[2];}
 #define VectorCopy(a,b) {(b)[0]=(a)[0];(b)[1]=(a)[1];(b)[2]=(a)[2];}
-#define VectorClear(a)			(a[0]=a[1]=a[2]=0)
+#define VectorClear(a)			((a)[0]=(a)[1]=(a)[2]=0)
 #define VectorNegate(a,b)		((b)[0]=-(a)[0],(b)[1]=-(a)[1],(b)[2]=-(a)[2])
 #define VectorLength(a)		Length(a)