Auto merge of #53530 - kennytm:rollup, r=kennytm

Rollup of 17 pull requests

Successful merges:

 - #53030 (Updated RELEASES.md for 1.29.0)
 - #53104 (expand the documentation on the `Unpin` trait)
 - #53213 (Stabilize IP associated constants)
 - #53296 (When closure with no arguments was expected, suggest wrapping)
 - #53329 (Replace usages of ptr::offset with ptr::{add,sub}.)
 - #53363 (add individual docs to `core::num::NonZero*`)
 - #53370 (Stabilize macro_vis_matcher)
 - #53393 (Mark libserialize functions as inline)
 - #53405 (restore the page title after escaping out of a search)
 - #53452 (Change target triple used to check for lldb in build-manifest)
 - #53462 (Document Box::into_raw returns non-null ptr)
 - #53465 (Remove LinkMeta struct)
 - #53492 (update lld submodule to include RISCV patch)
 - #53496 (Fix typos found by codespell.)
 - #53521 (syntax: Optimize some literal parsing)
 - #53540 (Moved issue-53157.rs into src/test/ui/consts/const-eval/)
 - #53551 (Avoid some Place clones.)

Failed merges:

r? @ghost

1 files changed, 4 insertions, 6 deletions

diff --git a/src/libsyntax/parse/mod.rs b/src/libsyntax/parse/mod.rs
index adf01197c6d..1136cda5ee3 100644
--- a/src/libsyntax/parse/mod.rs
+++ b/src/libsyntax/parse/mod.rs
@@ -533,7 +533,7 @@ fn byte_lit(lit: &str) -> (u8, usize) {
 fn byte_str_lit(lit: &str) -> Lrc<Vec<u8>> {
     let mut res = Vec::with_capacity(lit.len());
 
-    let error = |i| format!("lexer should have rejected {} at {}", lit, i);
+    let error = |i| panic!("lexer should have rejected {} at {}", lit, i);
 
     /// Eat everything up to a non-whitespace
     fn eat<I: Iterator<Item=(usize, u8)>>(it: &mut iter::Peekable<I>) {
@@ -552,12 +552,11 @@ fn byte_str_lit(lit: &str) -> Lrc<Vec<u8>> {
     loop {
         match chars.next() {
             Some((i, b'\\')) => {
-                let em = error(i);
-                match chars.peek().expect(&em).1 {
+                match chars.peek().unwrap_or_else(|| error(i)).1 {
                     b'\n' => eat(&mut chars),
                     b'\r' => {
                         chars.next();
-                        if chars.peek().expect(&em).1 != b'\n' {
+                        if chars.peek().unwrap_or_else(|| error(i)).1 != b'\n' {
                             panic!("lexer accepted bare CR");
                         }
                         eat(&mut chars);
@@ -574,8 +573,7 @@ fn byte_str_lit(lit: &str) -> Lrc<Vec<u8>> {
                 }
             },
             Some((i, b'\r')) => {
-                let em = error(i);
-                if chars.peek().expect(&em).1 != b'\n' {
+                if chars.peek().unwrap_or_else(|| error(i)).1 != b'\n' {
                     panic!("lexer accepted bare CR");
                 }
                 chars.next();