[clang] [clang][CodeGen] Emit file-scope compound literals in a constant context (PR #221390)

[Eli Friedman via cfe-commits]

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@@ -7449,6 +7449,31 @@ Sema::ActOnCompoundLiteral(SourceLocation LParenLoc, ParsedType Ty,
   return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, InitExpr);
 }
 
+/// Whether the \p Index-th element of the semantic form of \p ILE initializes
+/// a reference member, so that its initializer is a glvalue that binds.
+static bool initializesReferenceMember(const InitListExpr *ILE,
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efriedma-quic wrote:

Doing it this way is O(N^2) in the number of fields.

Can we just check if the initializer is an lvalue?  It shouldn't be possible to have an lvalue as an operand to a compound literal unless it's binding to a reference.

https://github.com/llvm/llvm-project/pull/221390