Rust-GCC / Rust-GCC/gccrs

cfg in file modules is not handled correctly

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bug
Dominant language
C++
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Description

// a.rs
#[path = "b.rs"]
mod module;

// b.rs
#[cfg(a)]
mod submod {}

#[cfg(not(a))]
mod submod {}

I expected to see this happen: compiles

Instead, this happened: error

./b.rs:5:1: error: redefined multiple times
    2 | mod submod {}
      | ~~~
......
    5 | mod submod {}
      | ^~~
Meta
  • What version of Rust GCC were you using, git sha if possible. 3d2a0c0445c2a1417dcc290b7a14e551c14fa421

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Research direction

Reproduce the issue using the a.rs and b.rs examples with Rust GCC commit 3d2a0c0445c2a1417dcc290b7a14e551c14fa421. Trace how the #[path] module and its #[cfg] declarations are processed; done means the example compiles without reporting submod as redefined.

Written by the indexing model from the issue text.

Assessment

Tech stack
rust
Domain
compilers
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
45/100

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