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

[Yanzuo Liu via cfe-commits]

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@@ -13745,6 +13753,11 @@ void Sema::DiagnoseUniqueObjectDuplication(const VarDecl *VD) {
 }
 
 void Sema::AddInitializerToDecl(Decl *RealDecl, Expr *Init, bool DirectInit) {
+  auto ResetDeclForInitializer = llvm::make_scope_exit([this]() {
+    if (this->ExprEvalContexts.empty())
----------------
zwuis wrote:

```suggestion
    if (!this->ExprEvalContexts.empty())
```


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