[clang] P3394 - C++26 Annotation (PR #166287)

[Yanzuo Liu via cfe-commits]

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@@ -6409,6 +6409,60 @@ static void handleRequiresCapabilityAttr(Sema &S, Decl *D,
   D->addAttr(RCA);
 }
 
+static void handleCxx26AnnotationAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
+  Expr *CE = AL.getArgAsExpr(0);
+  if (CE->isLValue()) {
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zwuis wrote:

I think most checks of `handleCxx26AnnotationAttr` should be (maybe indirectly) delegated to `CheckTemplateArgument` in SemaTemplate.cpp . `meta::reflect_constant(E)` requires `E` as a valid template argument.

https://github.com/llvm/llvm-project/pull/166287