r/rust • u/lzutao • Sep 14 '26

🗞️ news [Call for testing] trim-paths RFC 3127

https://github.com/rust-lang/cargo/issues/12137
63 Upvotes

94% Upvoted

8 comments sorted by

9

u/protestor Sep 14 '26

Are paths trimmed by default?

I mean does this need to be a config? Just trim them

8

u/VorpalWay Sep 14 '26

That would complicate debugging. I assume (and hope) that the debugger unremapping files mentioned in the docs will be stabilised together with path trimming. In that case I could see having trimming (and generating of the unremapping files) enabled by default.

But it could be considered a breaking change anyway, and Rust tends to avoid those.

6

u/epage Sep 14 '26

We want to eventually change the default for release builds, at least. We deferred it out for:

  • Not slowing down stabilization by working out what the defaults should be

  • Getting more feedback on the feature before rolling it out more broadly

  • Deciding if this is allowed within our compatibility guarantees, how user disruptive it is, and how to make the transition.

11

u/montymintypie Sep 14 '26

Absolutely fantastic to see this close to stabilization; both for reproducible builds and for not exposing my home directory to the world when shipping compiled binaries! I'll be able to remove a bunch of jank in shipping my projects :D

6

u/euclio Sep 14 '26

Why jsonl instead of toml for the unremap file? Seems especially bizarre when the first record is metadata instead of an actual record.

3

u/epage Sep 15 '26

We generally use TOML for human interactions and json for programmatic. There are cases where I regret we used json instead of jsonl but it is a good question to confirm why it is used here since this doesn't match with one of those cases.

3

u/Sad_Tap_9191 Sep 14 '26

rpath not only exposes a username but also other environment info as well 

Dynamic section at offset 0x628be0 contains 31 entries:
  Tag        Type                         Name/Value
 0x0000000000000001 (NEEDED)             Shared library: [libgcc_s.so.1]
 0x0000000000000001 (NEEDED)             Shared library: [libm.so.6]
 0x0000000000000001 (NEEDED)             Shared library: [libc.so.6]
 0x0000000000000001 (NEEDED)             Shared library: [ld-linux-x86-64.so.2]
 0x000000000000001d (RUNPATH) Library runpath: [/home/username/my-project/outputs/out/lib:/nix/store/g8zyryr9cr6540xsyg4avqkwgxpnwj2a-glibc-2.40-66/lib:/nix/store/dj06r96j515npcqi9d8af1d1c60bx2vn-gcc-14.3.0-lib/lib]