rust/tests/ui/error-codes/E0206.rs

#[derive(Copy, Clone)]
struct Bar;

impl Copy for &'static mut Bar { }
//~^ ERROR the trait `Copy` cannot be implemented for this type

fn main() {
}
Add new error code tests 2016-08-03 23:51:52 +00:00			`#[derive(Copy, Clone)]`
			`struct Bar;`

Move some implementations of Clone and Copy to libcore Add implementations of `Clone` and `Copy` for some primitive types to libcore so that they show up in the documentation. The concerned types are the following: * All primitive signed and unsigned integer types (`usize`, `u8`, `u16`, `u32`, `u64`, `u128`, `isize`, `i8`, `i16`, `i32`, `i64`, `i128`); * All primitive floating point types (`f32`, `f64`) * `bool` * `char` * `!` * Raw pointers (`const T` and `mut T`) * Shared references (`&'a T`) These types already implemented `Clone` and `Copy`, but the implementation was provided by the compiler. The compiler no longer provides these implementations and instead tries to look them up as normal trait implementations. The goal of this change is to make the implementations appear in the generated documentation. For `Copy` specifically, the compiler would reject an attempt to write an `impl` for the primitive types listed above with error `E0206`; this error no longer occurs for these types, but it will still occur for the other types that used to raise that error. The trait implementations are guarded with `#[cfg(not(stage0))]` because they are invalid according to the stage0 compiler. When the stage0 compiler is updated to a revision that includes this change, the attribute will have to be removed, otherwise the stage0 build will fail because the types mentioned above no longer implement `Clone` or `Copy`. For type variants that are variadic, such as tuples and function pointers, and for array types, the `Clone` and `Copy` implementations are still provided by the compiler, because the language is not expressive enough yet to be able to write the appropriate implementations in Rust. The initial plan was to add `impl` blocks guarded by `#[cfg(dox)]` to make them apply only when generating documentation, without having to touch the compiler. However, rustdoc's usage of the compiler still rejected those `impl` blocks. This is a [breaking-change] for users of `#![no_core]`, because they will now have to supply their own implementations of `Clone` and `Copy` for the primitive types listed above. The easiest way to do that is to simply copy the implementations from `src/libcore/clone.rs` and `src/libcore/marker.rs`. Fixes #25893 2018-02-12 06:17:32 +00:00			`impl Copy for &'static mut Bar { }`
may not => cannot 2023-03-07 23:55:51 +00:00			//~^ ERROR the trait `Copy` cannot be implemented for this type
Add new error code tests 2016-08-03 23:51:52 +00:00
			`fn main() {`
			`}`