Make sure loops_per_tick doesn't overflow to zero.

diff --git a/src/devices/timer.c b/src/devices/timer.c
index 070c487328a61e10a8e6a86390703f4dd289173b..662e0c6f5645be139fde64f9f300bcd0f17d9c52 100644 (file)
--- a/src/devices/timer.c
+++ b/src/devices/timer.c
@@ -57,8 +57,11 @@ timer_calibrate (void)
   /* Approximate loops_per_tick as the largest power-of-two
      still less than one timer tick. */
   loops_per_tick = 1u << 10;
-  while (!too_many_loops (loops_per_tick << 1))
-    loops_per_tick <<= 1;
+  while (!too_many_loops (loops_per_tick << 1)) 
+    {
+      loops_per_tick <<= 1;
+      ASSERT (loops_per_tick != 0);
+    }
 
   /* Refine the next 8 bits of loops_per_tick. */
   high_bit = loops_per_tick;