Auto merge of #123856 - matthiaskrgr:rollup-4v8rkfj, r=matthiaskrgr

Rollup of 8 pull requests

Successful merges:

 - #123204 (rustdoc: point at span in `include_str!`-ed md file)
 - #123223 (Fix invalid silencing of parsing error)
 - #123249 (do not add prolog for variadic naked functions)
 - #123825 (Call the panic hook for non-unwind panics in proc-macros)
 - #123833 (Update stdarch submodule)
 - #123841 (Improve diagnostic by suggesting to remove visibility qualifier)
 - #123849 (Update E0384.md)
 - #123852 (fix typo in library/std/src/lib.rs)

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

1 files changed, 7 insertions, 2 deletions

diff --git a/compiler/rustc_errors/src/emitter.rs b/compiler/rustc_errors/src/emitter.rs
index bd8e78bda26..6ce3fa3535d 100644
--- a/compiler/rustc_errors/src/emitter.rs
+++ b/compiler/rustc_errors/src/emitter.rs
@@ -1513,7 +1513,9 @@ impl HumanEmitter {
                 for line_idx in 0..annotated_file.lines.len() {
                     let file = annotated_file.file.clone();
                     let line = &annotated_file.lines[line_idx];
-                    if let Some(source_string) = file.get_line(line.line_index - 1) {
+                    if let Some(source_string) =
+                        line.line_index.checked_sub(1).and_then(|l| file.get_line(l))
+                    {
                         let leading_whitespace = source_string
                             .chars()
                             .take_while(|c| c.is_whitespace())
@@ -1553,7 +1555,10 @@ impl HumanEmitter {
                 for line in &annotated_file.lines {
                     max_line_len = max(
                         max_line_len,
-                        annotated_file.file.get_line(line.line_index - 1).map_or(0, |s| s.len()),
+                        line.line_index
+                            .checked_sub(1)
+                            .and_then(|l| annotated_file.file.get_line(l))
+                            .map_or(0, |s| s.len()),
                     );
                     for ann in &line.annotations {
                         span_right_margin = max(span_right_margin, ann.start_col.display);