rust/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs, branch 1.55.0

Improve debug symbol names to avoid ambiguity and work better with MSVC's debugger

2021-06-30T18:10:29+00:00

There are several cases where names of types and functions in the debug info are either ambiguous, or not helpful, such as including ambiguous placeholders (e.g., `{{impl}}`, `{{closure}}` or `dyn _'`) or dropping qualifications (e.g., for dynamic types). Instead, each debug symbol name should be unique and useful: * Include disambiguators for anonymous `DefPathDataName` (closures and generators), and unify their formatting when used as a path-qualifier vs item being qualified. * Qualify the principal trait for dynamic types. * If there is no principal trait for a dynamic type, emit all other traits instead. * Respect the `qualified` argument when emitting ref and pointer types. * For implementations, emit the disambiguator. * Print const generics when emitting generic parameters or arguments. Additionally, when targeting MSVC, its debugger treats many command arguments as C++ expressions, even when the argument is defined to be a symbol name. As such names in the debug info need to be more C++-like to be parsed correctly: * Avoid characters with special meaning (`#`, `[`, `"`, `+`). * Never start a name with `<` or `{` as this is treated as an operator. * `>>` is always treated as a right-shift, even when parsing generic arguments (so add a space to avoid this). * Emit function declarations using C/C++ style syntax (e.g., leading return type). * Emit arrays as a synthetic `array$` type. * Include a `$` in all synthetic types as this is a legal character for C++, but not Rust (thus we avoid collisions with user types).

Use () for entry_fn.

2021-05-12T11:58:42+00:00

Implement RFC 1260 with feature_name `imported_main`.

2021-04-29T00:35:08+00:00

Use iter::zip in compiler/

2021-03-26T16:32:31+00:00

Move debuginfo docs from `doc.rs` module to `doc.md` file

2021-03-20T21:38:49+00:00

And use `#[doc = include_str!("doc.md")]` in `mod.rs` so the docs are rendered as if they were inline in the root module.

Auto merge of #82285 - nhwn:nonzero-debug, r=nagisa

2021-03-07T20:23:23+00:00

Use u32 over Option in DebugLoc ~~Changes `Option` fields in `DebugLoc` to `Option`. Since the respective fields (`line` and `col`) are guaranteed to be 1-based, this layout optimization is a freebie.~~ EDIT: Changes `Option` fields in `DebugLoc` to `u32`. As `@bugadani` pointed out, an `Option` is probably an unnecessary layer of abstraction since the `None` variant is always used as `UNKNOWN_LINE_NUMBER` (which is just `0`). Also, `SourceInfo` in `metadata.rs` already uses a `u32` instead of an `Option` to encode the same information, so I think this change is warranted. Since `@jyn514` raised some concerns over measuring performance in a similar PR (#82255), does this need a perf run?

fix review

2021-02-25T01:21:12+00:00

replaced some map_or with map_or_else

2021-02-23T23:43:35+00:00

nhwn: use plain u32 in DebugLoc

2021-02-20T17:46:58+00:00

nhwn: use Option in DebugLoc

2021-02-20T17:46:50+00:00