Compile error with `#[derive(Type)]` starting from nightly-2024-04-05

[benwh1]

Bug Description

The code below does not compile on nightly-2024-04-05 or later.

Minimal Reproduction

use sqlx::Type;

#[derive(Type)]
struct Foo {
    a: i32,
}

fn main() {}

error: lifetime may not live long enough
  --> src/main.rs:3:10
   |
3  | #[derive(Type)]
   |          ^^^^
   |          |
   |          lifetime `'r` defined here
   |          requires that `'r` must outlive `'static`
   |          in this derive macro expansion
   |
  ::: /home/ben/.cargo/registry/src/index.crates.io-6f17d22bba15001f/sqlx-macros-0.7.4/src/lib.rs:43:1
   |
43 | pub fn derive_type(tokenstream: TokenStream) -> TokenStream {
   | ----------------------------------------------------------- in this expansion of `#[derive(Type)]`
   |
note: due to current limitations in the borrow checker, this implies a `'static` lifetime
  --> /home/ben/.cargo/registry/src/index.crates.io-6f17d22bba15001f/sqlx-postgres-0.7.4/src/types/record.rs:97:12
   |
97 |         T: for<'a> Decode<'a, Postgres> + Type<Postgres>,
   |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^

error: implementation of `sqlx::Decode` is not general enough
  --> src/main.rs:3:10
   |
3  | #[derive(Type)]
   |          ^^^^
   |          |
   |          implementation of `sqlx::Decode` is not general enough
   |          in this derive macro expansion
   |
  ::: /home/ben/.cargo/registry/src/index.crates.io-6f17d22bba15001f/sqlx-macros-0.7.4/src/lib.rs:43:1
   |
43 | pub fn derive_type(tokenstream: TokenStream) -> TokenStream {
   | ----------------------------------------------------------- in this expansion of `#[derive(Type)]`
   |
   = note: `i32` must implement `sqlx::Decode<'0, Postgres>`, for any lifetime `'0`...
   = note: ...but it actually implements `sqlx::Decode<'1, Postgres>`, for some specific lifetime `'1`

error: could not compile `testing` (bin "testing") due to 2 previous errors

Info

• SQLx version: sqlx = { version = "0.7.4", features = ["postgres"] }
• Database server and version: psql (PostgreSQL) 16.2 (Ubuntu 16.2-1.pgdg20.04+1)
• Operating system: Linux Mint 20.1 x86_64
• rustc --version: nightly-2024-04-05

[syphar]

For some context:

this is coming from https://github.com/rust-lang/rust/pull/119820, which is an intentional breaking change, coming to Rust 1.79. ( we at docs.rs are also impacted: https://github.com/rust-lang/docs.rs/issues/2488 )

[HHogg]

I'm also seeing this. On the plus side, I learned how to downgrade a rust version from this. If you're here and need to do the same, here's how...

# Install the version before the broken one. 
rustup install nightly-2024-04-04 

# Set the version to the installed one 
rustup override set nightly-2024-04-04

I can confirm nightly-2024-04-04 works fine.

[demurgos]

Bumping this issue: the problem happens in Rust 1.79 which is currently in beta. It is set to release this change in just 3 weeks! @lcnr posted a comment that they would try to delay the change, but so far it's still in the beta.

Please merge the PR with the fix without waiting too much, it already feels like it's cutting it fairly close.

[abonander]

closed by #2940

[42triangles]

Just in case anyone who's following this issue is wondering, the new stable release didn't break things depending on sqlx, they temporarily reverted the change: https://github.com/rust-lang/rust/pull/125629