diff --git a/src/engine/math_util.c b/src/engine/math_util.c
index c398243b3..19b1e79a4 100644
--- a/src/engine/math_util.c
+++ b/src/engine/math_util.c
@@ -736,7 +736,7 @@ static u16 atan2_lookup(f32 y, f32 x) {
         ret = gArctanTable[0];
     } else {
         s32 index = (s32)(y / x * 1024 + 0.5f);
-        if (index >= 0x401) { index = 0; }
+        if (index >= 0x401 || index < 0) { index = 0; }
         ret = gArctanTable[index];
     }
     return ret;
diff --git a/src/game/shadow.c b/src/game/shadow.c
index 5bbb4e9cb..c6315c633 100644
--- a/src/game/shadow.c
+++ b/src/game/shadow.c
@@ -234,6 +234,9 @@ s8 init_shadow(struct Shadow *s, f32 xPos, f32 yPos, f32 zPos, s16 shadowScale,
         s->floorNormalY = floorGeometry->normalY;
         s->floorNormalZ = floorGeometry->normalZ;
         s->floorOriginOffset = floorGeometry->originOffset;
+    } else {
+        // You can't draw a shadow with no floor under you.
+        return 1;
     }
 
     if (overwriteSolidity) {