From e5844b23b75e33ef37eb49b7d159304e27c3c4f2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Vladim=C3=ADr=20Vondru=C5=A1?= <mosra@centrum.cz>
Date: Sun, 9 Apr 2023 10:40:47 +0200
Subject: [PATCH] Math: use a more common integer rounding calculation in
 BitVector.

The

    (size - 1)/8 + 1

expression is the same as

    (size - 1)/8 + 8/8

which is the same as the following in all cases except when size == 0,
for which it underflows:

    (size - 1 + 8)/8 == (size + 7)/8

To avoid needless surprises, I'm changing to what's used everywhere
else, including the BitArray, and also reusing the already-calculated
value for the _data array size.
---
 src/Magnum/Math/BitVector.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/Magnum/Math/BitVector.h b/src/Magnum/Math/BitVector.h
index ab5a393b2..ef50a9e49 100644
--- a/src/Magnum/Math/BitVector.h
+++ b/src/Magnum/Math/BitVector.h
@@ -88,7 +88,7 @@ template<std::size_t size> class BitVector {
     public:
         enum: std::size_t {
             Size = size,                /**< Vector size */
-            DataSize = (size-1)/8+1     /**< Vector storage size */
+            DataSize = (size + 7)/8     /**< Vector storage size */
         };
 
         /**
@@ -303,7 +303,7 @@ template<std::size_t size> class BitVector {
         /* Implementation for Vector<size, T>::Vector(U) */
         template<std::size_t ...sequence> constexpr explicit BitVector(Corrade::Containers::Implementation::Sequence<sequence...>, UnsignedByte value): _data{Implementation::repeat(value, sequence)...} {}
 
-        UnsignedByte _data[(size-1)/8+1];
+        UnsignedByte _data[DataSize];
 };
 
 #ifndef CORRADE_NO_DEBUG