[clang] WIP: [clang] MicrosoftCXXABI: Fix exception copy constructor LUT after loading AST (PR #114075)

[Reid Kleckner via cfe-commits]

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@@ -249,6 +249,11 @@ FIELD(HasDeclaredCopyAssignmentWithConstParam, 1, MERGE_OR)
 /// base classes or fields have a no-return destructor
 FIELD(IsAnyDestructorNoReturn, 1, NO_MERGE)
 
+/// Microsoft CXX ABI specific:
+/// Whether the copy constructor is used by a `throw` expression.
+/// Used by ASTReader to restore the sidecar RecordToCopyCtor LUT.
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rnk wrote:

I don't think "LUT" is widely understood to be an abbreviation of Lookup table, so I would spell this out if you need it.

https://github.com/llvm/llvm-project/pull/114075