ByteString: Adjust bitfields for MSVC#1446
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copybara-service[bot] merged 1 commit intomasterfrom May 7, 2025
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ByteString: Adjust bitfields for MSVC#1446copybara-service[bot] merged 1 commit intomasterfrom unknown repository
ByteString: Adjust bitfields for MSVC#1446copybara-service[bot] merged 1 commit intomasterfrom
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Microsoft Visual C++ compiler has more restrictions than usual about bit fields. There are two restrictions that particularly break ByteString: - A consecutive field with a different type will force alignment to next boundary - The alignment boundary is based on the type of the bitfield Because of this, we can't use the enumeration type inside of the bitfield. Actually though, this is mostly OK: the header struct is the only one that actually needs a typed enum, and nothing follows it in the header struct. Therefore, this workaround should make all of GCC, Clang and MSVC happy. Also: fixes the #pragma pack directives, which are typo'd slightly.
jcking
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May 6, 2025
ghost
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Microsoft Visual C++ compiler has more restrictions than usual about bit fields. There are two restrictions that particularly break
ByteString:Because of this, we can't use the enumeration type inside of the bitfield. Actually though, this is mostly OK: the header struct is the only one that actually needs a typed enum, and nothing follows it in the header struct.
Therefore, this workaround should make all of GCC, Clang and MSVC happy.
Also: fixes the
#pragma packdirectives, which are typo'd slightly.P.S.: Yes, it must be
std::uint8_tand notuint8_t. It turns out MSVC actually ensures the typedefs are namespaced-only, if you include<cstdint>. This is correct AFAIK, although I've never seen behavior like that out of any of the other implementations. Dunno why this doesn't apply tosize_t, too.Related issue: #768