rust/compiler/rustc_mir_transform
Matthias Krüger 70e3f8d240
Rollup merge of #119033 - Zalathar:unicode, r=davidtwco
coverage: `llvm-cov` expects column numbers to be bytes, not code points

Normally the compiler emits column numbers as a 1-based number of Unicode code points.

But when we embed coverage mappings for `-Cinstrument-coverage`, those mappings will ultimately be read by the `llvm-cov` tool. That tool assumes that column numbers are 1-based numbers of *bytes*, and relies on that assumption when slicing up source code to apply highlighting (in HTML reports, and in text-based reports with colour).

For the very common case of all-ASCII source code, bytes and code points are the same, so the difference isn't noticeable. But for code that contains non-ASCII characters, emitting column numbers as code points will result in `llvm-cov` slicing strings in the wrong places, producing mangled output or fatal errors.

(See https://github.com/taiki-e/cargo-llvm-cov/issues/275 as an example of what can go wrong.)
2024-01-09 00:19:33 +01:00
..
src Rollup merge of #119033 - Zalathar:unicode, r=davidtwco 2024-01-09 00:19:33 +01:00
Cargo.toml coverage: Avoid unnecessary macros in unit tests 2023-12-07 11:12:48 +11:00
messages.ftl Print list of missing target features when calling a function with target features outside an unsafe block 2023-11-27 19:13:11 +01:00