[clang] [Clang] Consider reachability for file-scope warnings on initializers (PR #163885)

[Corentin Jabot via cfe-commits]

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@@ -6750,6 +6750,11 @@ class Sema final : public SemaBase {
     /// suffice, e.g., in a default function argument.
     Decl *ManglingContextDecl;
 
+    /// Declaration for initializer if one is currently being
+    /// parsed. Used when an expression has a possibly unreachable
+    /// diagnostic to reference the declaration as a whole.
+    VarDecl *DeclForInitializer = nullptr;
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cor3ntin wrote:

Would that be ever different from ManglingContextDecl? Can we reuse that?

https://github.com/llvm/llvm-project/pull/163885