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error: generic parameters may not be used in const operations
--> $DIR/const-argument-if-length.rs:18:24
|
LL | pad: [u8; is_zst::<T>()],
| ^ cannot perform const operation using `T`
|
= note: type parameters may not be used in const expressions
= help: add `#![feature(generic_const_exprs)]` to allow generic const expressions
error[E0277]: the size for values of type `T` cannot be known at compilation time
--> $DIR/const-argument-if-length.rs:16:12
|
LL | pub struct AtLeastByte<T: ?Sized> {
| - this type parameter needs to be `Sized`
LL | value: T,
| ^ doesn't have a size known at compile-time
|
= note: only the last field of a struct may have a dynamically sized type
= help: change the field's type to have a statically known size
help: consider removing the `?Sized` bound to make the type parameter `Sized`
|
LL - pub struct AtLeastByte<T: ?Sized> {
LL + pub struct AtLeastByte<T> {
|
help: borrowed types always have a statically known size
|
LL | value: &T,
| +
help: the `Box` type always has a statically known size and allocates its contents in the heap
|
LL | value: Box<T>,
| ++++ +
error[E0277]: the size for values of type `T` cannot be known at compilation time
--> $DIR/const-argument-if-length.rs:7:28
|
LL | pub const fn is_zst<T: ?Sized>() -> usize {
| - this type parameter needs to be `Sized`
LL | if std::mem::size_of::<T>() == 0 {
| ^ doesn't have a size known at compile-time
|
note: required by an implicit `Sized` bound in `std::mem::size_of`
--> $SRC_DIR/core/src/mem/mod.rs:LL:COL
help: consider removing the `?Sized` bound to make the type parameter `Sized`
|
LL - pub const fn is_zst<T: ?Sized>() -> usize {
LL + pub const fn is_zst<T>() -> usize {
|
error: aborting due to 3 previous errors
For more information about this error, try `rustc --explain E0277`.
|
