From dc046572def13a3eb625520c5a8bfd651b86f3a3 Mon Sep 17 00:00:00 2001
From: David Sherret <dsherret@users.noreply.github.com>
Date: Mon, 8 Apr 2024 21:21:03 -0400
Subject: [PATCH] fix(visit): Improve `Map` implementation for `Box` (#8819)

**Related issue (if exists):**

 - Closes #8817
---
 crates/swc_visit/src/util/map.rs | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/crates/swc_visit/src/util/map.rs b/crates/swc_visit/src/util/map.rs
index 1b3eb7d07b8c..992d2332645f 100644
--- a/crates/swc_visit/src/util/map.rs
+++ b/crates/swc_visit/src/util/map.rs
@@ -1,4 +1,4 @@
-use std::{mem, ptr};
+use std::ptr;
 
 /// Copied from `syntax::ptr::P` of rustc.
 pub trait Map<T> {
@@ -13,17 +13,15 @@ pub trait Map<T> {
 }
 
 impl<T> Map<T> for Box<T> {
-    fn map<F>(mut self, f: F) -> Self
+    fn map<F>(self, f: F) -> Self
     where
         F: FnOnce(T) -> T,
     {
-        let p: *mut T = &mut *self;
-
         // Leak self in case of panic.
         // FIXME(eddyb) Use some sort of "free guard" that
         // only deallocates, without dropping the pointee,
         // in case the call the `f` below ends in a panic.
-        mem::forget(self);
+        let p = Box::into_raw(self);
 
         unsafe {
             ptr::write(p, f(ptr::read(p)));