From 05c3a2b07dc66fabc874181ce1eebea192cb4b56 Mon Sep 17 00:00:00 2001
From: est31 <MTest31@outlook.com>
Date: Tue, 22 Sep 2020 15:30:09 +0200
Subject: [PATCH] Add #[track_caller] to more panicking Cell functions

Continuation of #74526

Adds the #[track_caller] attribute to almost all panicking Cell
functions. The ones that borrow two Cells in their function
body are spared, because the panic location helps pinpoint
which of the two borrows failed. You'd need to have
full debuginfo and backtraces enabled together with column
info in order to be able to discern the cases.
Column info is only available on non-Windows platforms.
---
 library/core/src/cell.rs | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/library/core/src/cell.rs b/library/core/src/cell.rs
index cbbfcb4611321..8d37cffeef556 100644
--- a/library/core/src/cell.rs
+++ b/library/core/src/cell.rs
@@ -700,6 +700,7 @@ impl<T> RefCell<T> {
     /// ```
     #[inline]
     #[stable(feature = "refcell_replace", since = "1.24.0")]
+    #[track_caller]
     pub fn replace(&self, t: T) -> T {
         mem::replace(&mut *self.borrow_mut(), t)
     }
@@ -722,6 +723,7 @@ impl<T> RefCell<T> {
     /// ```
     #[inline]
     #[stable(feature = "refcell_replace_swap", since = "1.35.0")]
+    #[track_caller]
     pub fn replace_with<F: FnOnce(&mut T) -> T>(&self, f: F) -> T {
         let mut_borrow = &mut *self.borrow_mut();
         let replacement = f(mut_borrow);
@@ -1056,6 +1058,7 @@ impl<T: Clone> Clone for RefCell<T> {
     ///
     /// Panics if the value is currently mutably borrowed.
     #[inline]
+    #[track_caller]
     fn clone(&self) -> RefCell<T> {
         RefCell::new(self.borrow().clone())
     }