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warning: taking a mutable reference to a `const` item
--> tests/ui-nightly/transmute-mut-const.rs:20:52
|
20 | const CONST_CONTEXT: &mut [u8; 2] = transmute_mut!(&mut ARRAY_OF_U8S);
| ^^^^^^^^^^^^^^^^^
|
= note: each usage of a `const` item creates a new temporary
= note: the mutable reference will refer to this temporary, not the original `const` item
note: `const` item defined here
--> tests/ui-nightly/transmute-mut-const.rs:17:1
|
17 | const ARRAY_OF_U8S: [u8; 2] = [0u8; 2];
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^
= note: `#[warn(const_item_mutation)]` on by default
error[E0658]: mutable references are not allowed in constants
--> tests/ui-nightly/transmute-mut-const.rs:20:52
|
20 | const CONST_CONTEXT: &mut [u8; 2] = transmute_mut!(&mut ARRAY_OF_U8S);
| ^^^^^^^^^^^^^^^^^
|
= help: add `#![feature(const_mut_refs)]` to the crate attributes to enable
error[E0015]: cannot call non-const fn `transmute_mut::<'_, '_, [u8; 2], [u8; 2]>` in constants
--> tests/ui-nightly/transmute-mut-const.rs:20:37
|
20 | const CONST_CONTEXT: &mut [u8; 2] = transmute_mut!(&mut ARRAY_OF_U8S);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
= note: calls in constants are limited to constant functions, tuple structs and tuple variants
= note: this error originates in the macro `transmute_mut` (in Nightly builds, run with -Z macro-backtrace for more info)
error[E0716]: temporary value dropped while borrowed
--> tests/ui-nightly/transmute-mut-const.rs:20:57
|
20 | const CONST_CONTEXT: &mut [u8; 2] = transmute_mut!(&mut ARRAY_OF_U8S);
| --------------------^^^^^^^^^^^^-
| | |
| | creates a temporary value which is freed while still in use
| temporary value is freed at the end of this statement
| using this value as a constant requires that borrow lasts for `'static`