1408622 - stylo: expected lifetime parameter with rust 1.21

Status: RESOLVED FIXED

(Core :: CSS Parsing and Computation, defect)

Description

[Ralph Giles (:rillian)]

Building stylo with rust 1.21.0 started failing recently.

>  error[E0106]: missing lifetime specifier
>      --> /builds/worker/workspace/build/src/obj-firefox/toolkit/library/x86_64-unknown-linux-gnu/release/build/style-c4949dd4c23a1f5b/out/gecko/bindings.rs:2129:9
>       |
>  2129 |      -> RawGeckoElementBorrowedOrNull;
>       |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected lifetime parameter
>       |
>       = help: this function's return type contains a borrowed value, but the signature does not say whether it is borrowed from argument 1 or argument 2
>  error: aborting due to previous error
>  error: Could not compile `style`.

Comment 1

[Ralph Giles (:rillian)]

Looks like maybe an issue with the bindgen output.

Comment 2

[Ralph Giles (:rillian)]

Looks like the culprit is bug 1407952. geckolib/glue.rs defines:

> pub unsafe extern "C" fn Servo_SelectorList_Closest<'a>(
>     element: RawGeckoElementBorrowed<'a>,
>     selectors: RawServoSelectorListBorrowed,
> ) -> RawGeckoElementBorrowedOrNull<'a>

SERVO_BINDING_FUNC() + bindgen turn this into:

> extern "C" {
>     pub fn Servo_SelectorList_Closest(arg1: RawGeckoElementBorrowed,
>                                       arg2: RawServoSelectorListBorrowed)
>      -> RawGeckoElementBorrowedOrNull;
> }

Dropping the lifetime annotation.

Comment 3

[Emilio Cobos Álvarez (:emilio)]

Yeah, I find our bindings stuff super over-engineered, and this is part of the problem with it :(

For now the easy solution is making that function use `const Element*` instead of `RawGeckoElementBorrowed`, and adjust the rust code too. We should look into removing all the boilerplate and magic of our binding functions IMO.

Comment 4

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/de9496ac2ea8
Dumb down the return value of Servo_SelectorList_Closest. r=me

Comment 5

[Sebastian Hengst [:aryx] (needinfo me if it's about an intermittent or backout)]

https://hg.mozilla.org/mozilla-central/rev/de9496ac2ea8