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Make Peripherals::steal() zero cost

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Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
45/100
Issue type
Refactor
Clarity
Mostly clear
Activity status
Stale
Tech stack
rust
Domain
embedded-iot

Research direction

Start in src/peripheral/mod.rs around line 180 and inspect how Peripherals::steal() constructs and returns the zero-sized Peripherals value. Confirm the implementation no longer performs the static mut write and remains safe under its existing contract; the completed change should make the function zero-cost.

Written by the indexing model from the issue text.

Description

Peripherals::steal() has a write to a static mut: https://github.com/rust-embedded/cortex-m/blob/6b013138b734b9bbeb24a345f75d2bcc1c69fa8d/src/peripheral/mod.rs#L180

I expected it to be zero-cost, just constructing and returning the Peripherals which is a noop since it is ZST. This was a bit surprising.

Dominant language
Rust
Stars
1k
Forks
201
Avg merge
1h 8m
Merged PRs (30d)
2

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