Auto merge of #81678 - jackh726:rollup-3nerni4, r=jackh726

Rollup of 14 pull requests

Successful merges:

 - #80593 (Upgrade Chalk)
 - #81260 (Add .editorconfig)
 - #81455 (Add AArch64 big-endian and ILP32 targets)
 - #81517 (Remove remnants of the santizer runtime crates from bootstrap)
 - #81530 (sys: use `process::abort()` instead of `arch::wasm32::unreachable()`)
 - #81544 (Add better diagnostic for unbounded Abst. Const)
 - #81588 (Add doc aliases for "delete")
 - #81603 (rustbuild: Don't build compiler twice for error-index-generator.)
 - #81634 (Add long explanation e0521)
 - #81636 (Directly use `Option<&[T]>` instead of converting from `Option<&Vec<T>>` later on)
 - #81647 (Fix bug with assert!() calling the wrong edition of panic!().)
 - #81655 (Improve wording of suggestion about accessing field)
 - #81665 (Fix out of date `Scalar` documentation)
 - #81671 (Add more associated type tests)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup

2 files changed, 29 insertions, 1 deletions

diff --git a/compiler/rustc_error_codes/src/error_codes.rs b/compiler/rustc_error_codes/src/error_codes.rs
index c669f7fed27..9ce74dd9b5a 100644
--- a/compiler/rustc_error_codes/src/error_codes.rs
+++ b/compiler/rustc_error_codes/src/error_codes.rs
@@ -267,6 +267,7 @@ E0516: include_str!("./error_codes/E0516.md"),
 E0517: include_str!("./error_codes/E0517.md"),
 E0518: include_str!("./error_codes/E0518.md"),
 E0520: include_str!("./error_codes/E0520.md"),
+E0521: include_str!("./error_codes/E0521.md"),
 E0522: include_str!("./error_codes/E0522.md"),
 E0524: include_str!("./error_codes/E0524.md"),
 E0525: include_str!("./error_codes/E0525.md"),
@@ -597,7 +598,6 @@ E0780: include_str!("./error_codes/E0780.md"),
     E0514, // metadata version mismatch
     E0519, // local crate and dependency have same (crate-name, disambiguator)
     // two dependencies have same (crate-name, disambiguator) but different SVH
-    E0521, // borrowed data escapes outside of closure
     E0523,
 //  E0526, // shuffle indices are not constant
 //  E0540, // multiple rustc_deprecated attributes
diff --git a/compiler/rustc_error_codes/src/error_codes/E0521.md b/compiler/rustc_error_codes/src/error_codes/E0521.md
new file mode 100644
index 00000000000..65dcac983ac
--- /dev/null
+++ b/compiler/rustc_error_codes/src/error_codes/E0521.md
@@ -0,0 +1,28 @@
+Borrowed data escapes outside of closure.
+
+Erroneous code example:
+
+```compile_fail,E0521
+let mut list: Vec<&str> = Vec::new();
+
+let _add = |el: &str| {
+    list.push(el); // error: `el` escapes the closure body here
+};
+```
+
+A type anotation of a closure parameter implies a new lifetime declaration.
+Consider to drop it, the compiler is reliably able to infer them.
+
+```
+let mut list: Vec<&str> = Vec::new();
+
+let _add = |el| {
+    list.push(el);
+};
+```
+
+See the [Closure type inference and annotation][closure-infere-annotation] and
+[Lifetime elision][lifetime-elision] sections of the Book for more details.
+
+[closure-infere-annotation]: https://doc.rust-lang.org/book/ch13-01-closures.html#closure-type-inference-and-annotation
+[lifetime-elision]: https://doc.rust-lang.org/reference/lifetime-elision.html