Visit const node in dead-code analysis
#118713
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The job Click to see the possible cause of the failure (guessed by this bot) |
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I think this is intentional. If anything, we need to check if the item name of the const starts with |
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Also, for the record, this also occurs in other items: fn foo() {}
//~^ WARN function `foo` is never used
fn _a() {
foo();
}I believe this should be fixed more consistently, then we can T-lang nominate this for their feedback. |
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@rustbot author |
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In variables, there is no warning about fn main() {
let x = 10;
let _y = x;
}
// There are no warnings.I may be mistaken, but I think the constants should be analyzed in the same way. const X: i32 = 10;
const _Y: i32 = X;
fn main() {}
/*
warning: constant `X` is never used
--> test.rs:20:7
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20 | const X: i32 = 10;
| ^
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= note: `#[warn(dead_code)]` on by default
*/ |
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Furthremore, in the following code, the type alias type T = u32;
const _A: () = assert!(std::mem::size_of::<T>() != std::mem::size_of::<T>());
fn main() {}
/*
warning: type alias `T` is never used
--> test.rs:1:6
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1 | type T = u32;
| ^
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= note: `#[warn(dead_code)]` on by default
error[E0080]: evaluation of constant value failed
--> test.rs:2:16
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2 | const _A: () = assert!(std::mem::size_of::<T>() != std::mem::size_of::<T>());
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the evaluated program panicked at 'assertion failed: std::mem::size_of::<T>() != std::mem::size_of::<T>()', test.rs:2:16
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= note: this error originates in the macro `assert` (in Nightly builds, run with -Z macro-backtrace for more info)
*/ |
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@long-long-float FYI: when a PR is ready for review, send a message containing |
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@JohnCSimon |
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Ping from triage: I'm closing this due to inactivity, Please reopen when you are ready to continue with this. @rustbot label: +S-inactive |
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the
S-inactive
close #118424
I fixed to visit
constnode in dead-code analysis.Before this PR, the body of
constnode is not visited in dead-code analysis.Therefore the type
Tis detected as adead_code.