#[thread_local] + #[no_mangle] produces a "symbol already defined" error on Windows targets
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A-thread-locals
C-bug
F-thread_local
O-windows
T-compiler
- Dominant language
- Rust
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- 119k
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Description
#![feature(thread_local)]
#[no_mangle]
#[thread_local]
pub static FOO: u32 = 3;
Does not compile on x86_64-pc-windows-msvc and x86_64-pc-windows-gnu, due to:
error: symbol `FOO` is already defined
--> lib.rs:5:1
|
5 | pub static FOO: u32 = 3;
| ^^^^^^^^^^^^^^^^^^^
error: aborting due to 1 previous error
Found this while working on https://github.com/rust-lang/rust/pull/134777
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- Open a pull request that references the issue number.
Research direction
Start with the lib.rs reproducer and compile it for x86_64-pc-windows-msvc and x86_64-pc-windows-gnu. Investigate how the compiler handles the combined #[thread_local] and #[no_mangle] attributes on those targets. The work is done when the example no longer produces the duplicate-symbol error.
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