[clang] [libcxx] [clang] Fix -Wuninitialized for values passed by const pointers (PR #147221)

[Richard Smith via cfe-commits]

================
@@ -453,7 +450,7 @@ void ClassifyRefs::VisitCallExpr(CallExpr *CE) {
       const auto *UO = dyn_cast<UnaryOperator>(Ex);
       if (UO && UO->getOpcode() == UO_AddrOf)
         Ex = UO->getSubExpr();
-      classify(Ex, Ignore);
+      classify(Ex, Use);
----------------
zygoloid wrote:

> Your suggestion does not cover the case:
> 
> ```
> void foo(const int *);
> void test() {
>   int v;
>   foo(&v);
> }
> ```

Correct. We intentionally don't warn on that -- a "const reference use" is neither treated as initializing nor as using the local variable.

https://github.com/llvm/llvm-project/pull/147221