Rust errors / Ownership and borrowing
Rust compiler error · checked with rustc 1.99.0
Rust error E0745: cannot take address of a temporary
What it meansThe address of temporary value was taken.
What rustc prints
error[E0745]: cannot take address of a temporary
--> main.rs:2:26
|
2 | let ptr = &raw const 2; // error!
| ^ temporary valueReal output of rustc 1.99.0 compiling the official example below (2021 edition). Your names and line numbers will differ; the first line is the part to match.
E0745Ownership and borrowing
Activein rustc 1.99.0
8related errors linked below
The compiler team's explanation
The address of temporary value was taken.
Erroneous code example:
fn temp_address() {
let ptr = &raw const 2; // error!
}In this example, 2 is destroyed right after the assignment, which means that ptr now points to an unavailable location.
To avoid this error, first bind the temporary to a named local variable:
fn temp_address() {
let val = 2;
let ptr = &raw const val; // ok!
}From rustc --explain E0745 (1.99.0), part of the Rust project, MIT or Apache-2.0. Official page.
Related errors
- E0382borrow of moved value
- E0499cannot borrow as mutable more than once at a time
- E0502cannot borrow as mutable because it is also borrowed as immutable
- E0106missing lifetime specifier
- E0716temporary value dropped while borrowed
- E0726implicit elided lifetime not allowed here
- E0747type provided when a lifetime was expected
- E0764mutable borrows of temporaries that have their lifetime extended until the end of the program are not allowed
Up next
Often hit nextE0382: borrow of moved valueA related error from the same family.Read it next →Did this answer your question?