common: fix bitfield aliasing on GCC/Clang

This commit is contained in:
Liam 2022-07-09 20:33:03 -04:00
parent 313f047f97
commit a1c1ad096d

View file

@ -146,7 +146,16 @@ public:
} }
constexpr void Assign(const T& value) { constexpr void Assign(const T& value) {
#ifdef _MSC_VER
storage = static_cast<StorageType>((storage & ~mask) | FormatValue(value)); storage = static_cast<StorageType>((storage & ~mask) | FormatValue(value));
#else
// Explicitly reload with memcpy to avoid compiler aliasing quirks
// regarding optimization: GCC/Clang clobber chained stores to
// different bitfields in the same struct with the last value.
StorageTypeWithEndian storage_;
std::memcpy(&storage_, &storage, sizeof(storage_));
storage = static_cast<StorageType>((storage_ & ~mask) | FormatValue(value));
#endif
} }
[[nodiscard]] constexpr T Value() const { [[nodiscard]] constexpr T Value() const {