xcb_mask must not be zero when n == 32.

left shift of a 32-bit value by 32 is undefined, don't try to use it.

1 files changed, 1 insertions, 1 deletions

diff --git a/aux/xcb_bitops.h b/aux/xcb_bitops.h
index 48c3401..a6872a1 100644
--- a/aux/xcb_bitops.h
+++ b/aux/xcb_bitops.h
@@ -51,7 +51,7 @@
 _X_INLINE static uint32_t
 xcb_mask(uint32_t n)
 {
-    return (1 << n) - 1;
+    return n == 32 ? ~0 : (1 << n) - 1;
 }