Stabilize `-Zdwarf-version` as `-Cdwarf-version` I propose stabilizing `-Zdwarf-version` as `-Cdwarf-version`. This PR adds a new `-Cdwarf-version` flag, leaving the unstable `-Z` flag as is to ease the transition period. The `-Z` flag will be removed in the future. # `-Zdwarf-version` stabilization report ## What is the RFC for this feature and what changes have occurred to the user-facing design since the RFC was finalized? No RFC/MCP, this flag was added in https://github.com/rust-lang/rust/pull/98350 and was not deemed large enough to require additional process. The tracking issue for this feature is #103057. ## What behavior are we committing to that has been controversial? Summarize the major arguments pro/con. None that has been extensively debated but there are a few questions that could have been chosen differently: 1. What should the flag name be? The current flag name is very specific to DWARF. Other debuginfo formats exist (msvc's CodeView format or https://en.wikipedia.org/wiki/Stabs) so we could have chosen to generalize the flag name (`-{C,Z} debuginfo-version=dwarf-5` for example). While this would extend cleanly to support formats other than DWARF, there are some downsides to this design. Neither CodeView nor Stabs have specification or format versions so it's not clear what values would be supported beyond `dwarf-{2,3,4,5}` or `codeview`. We would also need to take care to ensure the name does not lead users to think they can pick a format other than one supported by the target. For instance, what would `--target x86_64-pc-windows-msvc -Cdebuginfo-version=dwarf-5` do? 2. What is the behavior when flag is used on targets that do not support DWARF? Currently, passing `-{C,Z} dwarf-version` on targets like `*-windows-msvc` does not do anything. It may be preferable to emit a warning alerting the user that the flag has no effect on the target platform. Alternatively, we could emit an error but this could be annoying since it would require the use of target specific RUSTFLAGS to use the flag correctly (and there isn't a way to target "any platform that uses DWARF" using cfgs). 3. Does the precompiled standard library potentially using a different version of DWARF a problem? I don't believe this is an issue as debuggers (and other such tools) already must deal with the possibility that an application uses different DWARF versions across its statically or dynamically linked libraries. ## Are there extensions to this feature that remain unstable? How do we know that we are not accidentally committing to those. No extensions per se, although future DWARF versions could be considered as such. At present, we validate the requested DWARF version is between 2 and 5 (inclusive) so new DWARF versions will not automatically be supported until the validation logic is adjusted. ## Summarize the major parts of the implementation and provide links into the code (or to PRs) - Targets define their preferred or default DWARF version: |
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This directory contains some source code for the Rust project, including:
- The bootstrapping build system
- Various submodules for tools, like cargo, tidy, etc.
For more information on how various parts of the compiler work, see the rustc dev guide.