diff --git a/Xi/extinit.c b/Xi/extinit.c
index ab774405be..7134df5b4b 100644
--- a/Xi/extinit.c
+++ b/Xi/extinit.c
@@ -1061,7 +1061,7 @@ MakeDeviceTypeAtoms(void)
  *
  *	Swap any events defined in this extension.
  */
-#define DO_SWAP(func,type) func ((type *)from, (type *)to)
+#define DO_SWAP(func,type) (func) ((type *)from, (type *)to)
 
 static void _X_COLD
 SEventIDispatch(xEvent *from, xEvent *to)
diff --git a/Xi/opendev.c b/Xi/opendev.c
index 1f69b6643a..b50f0847af 100644
--- a/Xi/opendev.c
+++ b/Xi/opendev.c
@@ -76,8 +76,8 @@ extern CARD8 event_base[];
  */
 
 #define WRITE_ICI(cls) do { \
-        x_rpcbuf_write_CARD8(&rpcbuf, cls); \
-        x_rpcbuf_write_CARD8(&rpcbuf, event_base[cls]); \
+        x_rpcbuf_write_CARD8(&rpcbuf, (cls)); \
+        x_rpcbuf_write_CARD8(&rpcbuf, event_base[(cls)]); \
         num_classes++; \
     } while (0)
 
diff --git a/Xi/xibarriers.c b/Xi/xibarriers.c
index b28e431180..53d53a8473 100644
--- a/Xi/xibarriers.c
+++ b/Xi/xibarriers.c
@@ -101,8 +101,8 @@ typedef struct _BarrierScreen {
 } BarrierScreenRec, *BarrierScreenPtr;
 
 #define GetBarrierScreen(s) ((BarrierScreenPtr)dixLookupPrivate(&(s)->devPrivates, BarrierScreenPrivateKey))
-#define GetBarrierScreenIfSet(s) GetBarrierScreen(s)
-#define SetBarrierScreen(s,p) dixSetPrivate(&(s)->devPrivates, BarrierScreenPrivateKey, p)
+#define GetBarrierScreenIfSet(s) GetBarrierScreen((s))
+#define SetBarrierScreen(s,p) dixSetPrivate(&(s)->devPrivates, BarrierScreenPrivateKey, (p))
 
 static struct PointerBarrierDevice *AllocBarrierDevice(void)
 {
@@ -209,7 +209,7 @@ inside_segment(int v, int v1, int v2)
         return v >= v1 && v <= v2;
 }
 
-#define T(v, a, b) (((float)v) - (a)) / ((b) - (a))
+#define T(v, a, b) (((float)(v)) - (a)) / ((b) - (a))
 #define F(t, a, b) ((t) * ((a) - (b)) + (a))
 
 /**