[clang] [Clang][Sema] Fix an ICE where structured binding packs within a lambda were not added to the CapturingScopeInfo (PR #214716)

[Ambrose Leeb via cfe-commits]

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@@ -924,6 +924,11 @@ Sema::ActOnDecompositionDeclarator(Scope *S, Declarator &D,
 
     auto *BD = BindingDecl::Create(Context, DC, B.NameLoc, B.Name, QT);
 
+    if (BD->isParameterPack()) {
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Sirraide wrote:

Yeah, I agree; I also quite dislike code duplication. Another reason is that it makes it hard to see at a glance whether two similar code blocks are actually doing the same thing or not (and if they aren’t, whether that’s intentional).

https://github.com/llvm/llvm-project/pull/214716