Be more careful with type of left operand of <<

On a 32-bit system, evaluating 1<<31 causes undefined behaviour because
1 is signed and so it produces signed overflow.  UBSan has spotted a
couple of occasions where this happens in Puzzles, so in each case I've
converted the left operand to the unsigned result type we actually want.

1 files changed, 2 insertions, 2 deletions

diff --git a/cube.c b/cube.c
index 69a9d35..3b4e975 100644
--- a/cube.c
+++ b/cube.c
@@ -202,8 +202,8 @@ struct game_grid {
 };
 
 #define SET_SQUARE(state, i, val) \
-    ((state)->bluemask[(i)/32] &= ~(1 << ((i)%32)), \
-     (state)->bluemask[(i)/32] |= ((!!val) << ((i)%32)))
+    ((state)->bluemask[(i)/32] &= ~(1UL << ((i)%32)), \
+     (state)->bluemask[(i)/32] |= ((unsigned long)(!!val) << ((i)%32)))
 #define GET_SQUARE(state, i) \
     (((state)->bluemask[(i)/32] >> ((i)%32)) & 1)