mirror of
https://github.com/rust-lang/rust.git
synced 2024-11-30 10:45:18 +00:00
42 lines
1.1 KiB
Rust
42 lines
1.1 KiB
Rust
// revisions:rpass1 rpass2
|
|
|
|
// This test case makes sure re-order the methods in a vtable will
|
|
// trigger recompilation of codegen units that instantiate it.
|
|
//
|
|
// See https://github.com/rust-lang/rust/issues/89598
|
|
|
|
trait Foo {
|
|
#[cfg(rpass1)]
|
|
fn method1(&self) -> u32;
|
|
|
|
fn method2(&self) -> u32;
|
|
|
|
#[cfg(rpass2)]
|
|
fn method1(&self) -> u32;
|
|
}
|
|
|
|
impl Foo for u32 {
|
|
fn method1(&self) -> u32 { 17 }
|
|
fn method2(&self) -> u32 { 42 }
|
|
}
|
|
|
|
fn main() {
|
|
// Before #89598 was fixed, the vtable allocation would be cached during
|
|
// a MIR optimization pass and then the codegen pass for the main object
|
|
// file would not register a dependency on it (because of the missing
|
|
// dep-tracking).
|
|
//
|
|
// In the rpass2 session, the main object file would not be re-compiled,
|
|
// thus the mod1::foo(x) call would pass in an outdated vtable, while the
|
|
// mod1 object would expect the new, re-ordered vtable, resulting in a
|
|
// call to the wrong method.
|
|
let x: &dyn Foo = &0u32;
|
|
assert_eq!(mod1::foo(x), 17);
|
|
}
|
|
|
|
mod mod1 {
|
|
pub(super) fn foo(x: &dyn super::Foo) -> u32 {
|
|
x.method1()
|
|
}
|
|
}
|