[clang] Implement [[msvc::no_unique_address]] (PR #65675)

[Christopher Di Bella via cfe-commits]

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@@ -2999,17 +3139,17 @@ void MicrosoftRecordLayoutBuilder::layoutBitField(const FieldDecl *FD) {
     auto NewSize = Context.toCharUnitsFromBits(
         llvm::alignDown(FieldBitOffset, Context.toBits(Info.Alignment)) +
         Context.toBits(Info.Size));
-    Size = std::max(Size, NewSize);
+    DataSize = Size = std::max(Size, NewSize);
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cjdb wrote:

I'd prefer it if we didn't have cascading assignment please.

https://github.com/llvm/llvm-project/pull/65675