--- /dev/null
+#![feature(min_const_generics)]
+
+pub const fn is_zst<T: ?Sized>() -> usize {
+ if std::mem::size_of::<T>() == 0 {
+ 1
+ } else {
+ 0
+ }
+}
+
+pub struct AtLeastByte<T: ?Sized> {
+ value: T,
+ //~^ ERROR the size for values of type `T` cannot be known at compilation time
+ pad: [u8; is_zst::<T>()],
+ //~^ ERROR generic parameters must not be used inside of non trivial constant values
+}
+
+fn main() {}
--- /dev/null
+error: generic parameters must not be used inside of non trivial constant values
+ --> $DIR/const-argument-if-length.rs:14:24
+ |
+LL | pad: [u8; is_zst::<T>()],
+ | ^ non-trivial anonymous constants must not depend on the parameter `T`
+ |
+ = note: type parameters are currently not permitted in anonymous constants
+
+error[E0277]: the size for values of type `T` cannot be known at compilation time
+ --> $DIR/const-argument-if-length.rs:12:12
+ |
+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: 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: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0277`.
--- /dev/null
+#![feature(min_const_generics)]
+
+const fn foo(n: usize) -> usize { n * 2 }
+
+fn bar<const N: usize>() -> [u32; foo(N)] {
+ //~^ ERROR generic parameters must not be used inside of non trivial constant values
+ [0; foo(N)]
+ //~^ ERROR generic parameters must not be used inside of non trivial constant values
+}
+
+fn main() {}
--- /dev/null
+#![feature(min_const_generics)]
+
+fn foo<const A: usize, const B: usize>(bar: [usize; A + B]) {}
+//~^ ERROR generic parameters must not be used inside of non trivial constant values
+//~| ERROR generic parameters must not be used inside of non trivial constant values
+
+fn main() {}
--- /dev/null
+error: generic parameters must not be used inside of non trivial constant values
+ --> $DIR/generic-sum-in-array-length.rs:3:53
+ |
+LL | fn foo<const A: usize, const B: usize>(bar: [usize; A + B]) {}
+ | ^ non-trivial anonymous constants must not depend on the parameter `A`
+ |
+ = help: it is currently only allowed to use either `A` or `{ A }` as generic constants
+
+error: generic parameters must not be used inside of non trivial constant values
+ --> $DIR/generic-sum-in-array-length.rs:3:57
+ |
+LL | fn foo<const A: usize, const B: usize>(bar: [usize; A + B]) {}
+ | ^ non-trivial anonymous constants must not depend on the parameter `B`
+ |
+ = help: it is currently only allowed to use either `B` or `{ B }` as generic constants
+
+error: aborting due to 2 previous errors
+
--- /dev/null
+#![feature(min_const_generics)]
+#![feature(core_intrinsics)]
+
+trait Trait<const S: &'static str> {}
+//~^ ERROR `&'static str` is forbidden as the type of a const generic parameter
+
+struct Bug<T>
+where
+ T: Trait<{std::intrinsics::type_name::<T>()}>
+ //~^ ERROR generic parameters must not be used inside of non trivial constant values
+{
+ t: T
+}
+
+fn main() {}
--- /dev/null
+error: generic parameters must not be used inside of non trivial constant values
+ --> $DIR/intrinsics-type_name-as-const-argument.rs:9:44
+ |
+LL | T: Trait<{std::intrinsics::type_name::<T>()}>
+ | ^ non-trivial anonymous constants must not depend on the parameter `T`
+ |
+ = note: type parameters are currently not permitted in anonymous constants
+
+error: `&'static str` is forbidden as the type of a const generic parameter
+ --> $DIR/intrinsics-type_name-as-const-argument.rs:4:22
+ |
+LL | trait Trait<const S: &'static str> {}
+ | ^^^^^^^^^^^^
+ |
+ = note: the only supported types are integers, `bool` and `char`
+ = note: more complex types are supported with `#[feature(const_generics)]`
+
+error: aborting due to 2 previous errors
+
--- /dev/null
+#![feature(min_const_generics)]
+
+struct Bug<T> {
+ //~^ ERROR parameter `T` is never used
+ inner: [(); { [|_: &T| {}; 0].len() }],
+ //~^ ERROR generic parameters must not be used inside of non trivial constant values
+}
+
+fn main() {}
--- /dev/null
+error: generic parameters must not be used inside of non trivial constant values
+ --> $DIR/issue-67375.rs:5:25
+ |
+LL | inner: [(); { [|_: &T| {}; 0].len() }],
+ | ^ non-trivial anonymous constants must not depend on the parameter `T`
+ |
+ = note: type parameters are currently not permitted in anonymous constants
+
+error[E0392]: parameter `T` is never used
+ --> $DIR/issue-67375.rs:3:12
+ |
+LL | struct Bug<T> {
+ | ^ unused parameter
+ |
+ = help: consider removing `T`, referring to it in a field, or using a marker such as `PhantomData`
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0392`.
--- /dev/null
+#![feature(min_const_generics)]
+
+use std::marker::PhantomData;
+
+use std::mem::{self, MaybeUninit};
+
+struct Bug<S> {
+ //~^ ERROR parameter `S` is never used
+ A: [(); {
+ let x: S = MaybeUninit::uninit();
+ //~^ ERROR generic parameters must not be used inside of non trivial constant values
+ let b = &*(&x as *const _ as *const S);
+ //~^ ERROR generic parameters must not be used inside of non trivial constant values
+ 0
+ }],
+}
+
+fn main() {}
--- /dev/null
+error: generic parameters must not be used inside of non trivial constant values
+ --> $DIR/issue-67945-1.rs:10:16
+ |
+LL | let x: S = MaybeUninit::uninit();
+ | ^ non-trivial anonymous constants must not depend on the parameter `S`
+ |
+ = note: type parameters are currently not permitted in anonymous constants
+
+error: generic parameters must not be used inside of non trivial constant values
+ --> $DIR/issue-67945-1.rs:12:45
+ |
+LL | let b = &*(&x as *const _ as *const S);
+ | ^ non-trivial anonymous constants must not depend on the parameter `S`
+ |
+ = note: type parameters are currently not permitted in anonymous constants
+
+error[E0392]: parameter `S` is never used
+ --> $DIR/issue-67945-1.rs:7:12
+ |
+LL | struct Bug<S> {
+ | ^ unused parameter
+ |
+ = help: consider removing `S`, referring to it in a field, or using a marker such as `PhantomData`
+
+error: aborting due to 3 previous errors
+
+For more information about this error, try `rustc --explain E0392`.
--- /dev/null
+#![feature(min_const_generics)]
+
+use std::mem::MaybeUninit;
+
+struct Bug<S> {
+ //~^ ERROR parameter `S` is never used
+ A: [(); {
+ let x: S = MaybeUninit::uninit();
+ //~^ ERROR generic parameters must not be used inside of non trivial constant values
+ let b = &*(&x as *const _ as *const S);
+ //~^ ERROR generic parameters must not be used inside of non trivial constant values
+ 0
+ }],
+}
+
+fn main() {}
--- /dev/null
+error: generic parameters must not be used inside of non trivial constant values
+ --> $DIR/issue-67945-2.rs:8:16
+ |
+LL | let x: S = MaybeUninit::uninit();
+ | ^ non-trivial anonymous constants must not depend on the parameter `S`
+ |
+ = note: type parameters are currently not permitted in anonymous constants
+
+error: generic parameters must not be used inside of non trivial constant values
+ --> $DIR/issue-67945-2.rs:10:45
+ |
+LL | let b = &*(&x as *const _ as *const S);
+ | ^ non-trivial anonymous constants must not depend on the parameter `S`
+ |
+ = note: type parameters are currently not permitted in anonymous constants
+
+error[E0392]: parameter `S` is never used
+ --> $DIR/issue-67945-2.rs:5:12
+ |
+LL | struct Bug<S> {
+ | ^ unused parameter
+ |
+ = help: consider removing `S`, referring to it in a field, or using a marker such as `PhantomData`
+
+error: aborting due to 3 previous errors
+
+For more information about this error, try `rustc --explain E0392`.
--- /dev/null
+#![feature(min_const_generics)]
+
+struct Bug<S: ?Sized> {
+ A: [(); {
+ let x: Option<Box<Self>> = None;
+ //~^ ERROR generic `Self` types are currently not permitted in anonymous constants
+ 0
+ }],
+ B: S
+}
+
+fn main() {}
--- /dev/null
+error: generic `Self` types are currently not permitted in anonymous constants
+ --> $DIR/issue-67945-3.rs:5:27
+ |
+LL | let x: Option<Box<Self>> = None;
+ | ^^^^
+
+error: aborting due to previous error
+
--- /dev/null
+#![feature(min_const_generics)]
+
+fn a<const X: &'static [u32]>() {}
+//~^ ERROR `&'static [u32]` is forbidden as the type of a const generic parameter
+
+fn main() {
+ a::<{&[]}>();
+}
--- /dev/null
+error: `&'static [u32]` is forbidden as the type of a const generic parameter
+ --> $DIR/static-reference-array-const-param.rs:3:15
+ |
+LL | fn a<const X: &'static [u32]>() {}
+ | ^^^^^^^^^^^^^^
+ |
+ = note: the only supported types are integers, `bool` and `char`
+ = note: more complex types are supported with `#[feature(const_generics)]`
+
+error: aborting due to previous error
+
--- /dev/null
+#![feature(min_const_generics)]
+
+struct Const<const P: &'static ()>;
+//~^ ERROR `&'static ()` is forbidden as the type of a const generic parameter
+
+fn main() {
+ const A: &'static () = unsafe {
+ std::mem::transmute(10 as *const ())
+ };
+
+ let _ = Const::<{A}>;
+}
--- /dev/null
+error: `&'static ()` is forbidden as the type of a const generic parameter
+ --> $DIR/transmute-const-param-static-reference.rs:3:23
+ |
+LL | struct Const<const P: &'static ()>;
+ | ^^^^^^^^^^^
+ |
+ = note: the only supported types are integers, `bool` and `char`
+ = note: more complex types are supported with `#[feature(const_generics)]`
+
+error: aborting due to previous error
+
projects / rust.git / commitdiff