static_cast<size_t> for QByteArray::size with std::max #4406
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src/util/cache.cpp
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| @@ -16,7 +16,7 @@ cache_key_t cacheKeyFromMessageDigest(const QByteArray& messageDigest) { | |||
| // 5 Hash function Usage | |||
| // 5.1 Truncated Message Digest | |||
| const auto significantByteCount = math_min( | |||
| messageDigest.size(), | |||
| static_cast<int>(messageDigest.size()), | |||
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Instead better remove the static_cast<int> casts. This should work. I expect that qsizetype is an alias for size_t on all platforms.
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I tried. It does not work with Qt5.
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Unfortunately I did not find documentation on qsizetype.
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size_t is unsigned
qsizetype is ptrdiff_t wich is the signed counterpart.
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So, what do you suggest as an alternative solution? Or just merge this?
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https://doc.qt.io/qt-5/qtglobal.html#qsizetype-alias
We should either cast to qsizetype or size_t. Since the size() cannot be negative and sizeof is implicitly of type size_t this would be my preferred choice.
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src/util/cache.cpp
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| for (auto i = 0; i < significantByteCount; ++i) { | ||
| static_cast<size_t>(messageDigest.size()), | ||
| sizeof(cache_key_t)); | ||
| for (unsigned int i = 0; i < significantByteCount; ++i) { |
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| for (unsigned int i = 0; i < significantByteCount; ++i) { | |
| for (size_t i = 0; i < significantByteCount; ++i) { |
The case that size_t is an unsigned type can be considered as design flaw of the early c++ standard.
In Mixxx we have introduced SINT as ptrdiff_t because it allows auto factorization.
Line 13 in f2d670e
So If you looking for a general patter to resolve this issue use ptrdiff_t.
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QByteArray::size returns qsizetype in Qt6, which needs to be converted to size_t to pass to std::max.
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CI passed. Merge? |
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Thank you. |
QByteArray::size returns qsizetype in Qt6, which needs to be
converted to an int to pass to std::max.