Check for #[rustc_as_ptr] attribute instead of searching for function names

Co-authored-by: Urgau <[email protected]>

Author: gavincrawford

compiler/rustc_lint/src/dangling.rs

@@ -133,10 +133,11 @@ impl DanglingPointerSearcher<'_, '_> {
 
 fn lint_expr(cx: &LateContext<'_>, expr: &Expr<'_>) {
     if let ExprKind::MethodCall(method, receiver, _args, _span) = expr.kind
-        && matches!(method.ident.name, sym::as_ptr | sym::as_mut_ptr)
+        && let Some(fn_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id)
+        && cx.tcx.has_attr(fn_id, sym::rustc_as_ptr)
         && is_temporary_rvalue(receiver)
         && let ty = cx.typeck_results().expr_ty(receiver)
-        && is_interesting(cx.tcx, ty)
+        && owns_allocation(cx.tcx, ty)
     {
         // FIXME: use `emit_node_lint` when `#[primary_span]` is added.
         cx.tcx.emit_node_span_lint(
@@ -201,14 +202,14 @@ fn is_temporary_rvalue(expr: &Expr<'_>) -> bool {
 
 // Array, Vec, String, CString, MaybeUninit, Cell, Box<[_]>, Box<str>, Box<CStr>,
 // or any of the above in arbitrary many nested Box'es.
-fn is_interesting(tcx: TyCtxt<'_>, ty: Ty<'_>) -> bool {
+fn owns_allocation(tcx: TyCtxt<'_>, ty: Ty<'_>) -> bool {
     if ty.is_array() {
         true
     } else if let Some(inner) = ty.boxed_ty() {
         inner.is_slice()
             || inner.is_str()
             || inner.ty_adt_def().is_some_and(|def| tcx.is_lang_item(def.did(), LangItem::CStr))
-            || is_interesting(tcx, inner)
+            || owns_allocation(tcx, inner)
     } else if let Some(def) = ty.ty_adt_def() {
         for lang_item in [LangItem::String, LangItem::MaybeUninit] {
             if tcx.is_lang_item(def.did(), lang_item) {