diff --git a/apps/Kernel/LowPowerTimerDriverP.nc b/apps/Kernel/LowPowerTimerDriverP.nc
index a8067ed6d4..75c0bc9dc7 100644
--- a/apps/Kernel/LowPowerTimerDriverP.nc
+++ b/apps/Kernel/LowPowerTimerDriverP.nc
@@ -43,7 +43,7 @@ implementation
 
     void enqueue_cb(uint16_t idx)
     {
-        if ((cb_widx + 1) & (CBQUEUESIZE-1) == cb_ridx)
+        if (((cb_widx + 1) & (CBQUEUESIZE - 1)) == cb_ridx)
             return; //drop
         callback_queue[cb_widx] = timer_buffer[idx].cb;
         cb_widx = (cb_widx+1) & (CBQUEUESIZE-1);
@@ -188,4 +188,4 @@ implementation
         post update_queues();
     }
 
-}
\ No newline at end of file
+}
diff --git a/apps/Kernel/StormSimpleGPIOP.nc b/apps/Kernel/StormSimpleGPIOP.nc
index 3b724c748a..135396a5d4 100644
--- a/apps/Kernel/StormSimpleGPIOP.nc
+++ b/apps/Kernel/StormSimpleGPIOP.nc
@@ -223,7 +223,7 @@ implementation
                 uint8_t port = arg0 >> 8;
                 uint8_t pin = arg0 & 0xFF;
                 uint32_t pinmask = 1 << (arg0 & 0xFF);
-                if ((irq_allowed[port] & pinmask == 0))
+                if ((irq_allowed[port] & pinmask) == 0)
                     return (uint32_t) -1;
                 irq_callback[port][pin].addr = arg2;
                 irq_callback[port][pin].r = (void*) argx[0];
diff --git a/apps/Kernel/TimerDriverP.nc b/apps/Kernel/TimerDriverP.nc
index 724cf71d77..6c0f9ba42b 100644
--- a/apps/Kernel/TimerDriverP.nc
+++ b/apps/Kernel/TimerDriverP.nc
@@ -196,7 +196,7 @@ implementation
             }
             case 0x05: //cancel(id) ->int32 0 for ok -1 for fail
             {
-                if (arg0 >= BUFSIZE) return (uint32_t)-1;
+                if (arg0 >= BUFSIZE) return (uint32_t) -1;
                 if (timer_buffer[arg0].flags == 0) return (uint32_t) -2;
                 timer_buffer[arg0].flags = 0;
                 return 0;