error[E0744]: `for` is not allowed in a `const fn`
  --> $DIR/const-fn-error.rs:5:5
   |
LL | /     for i in 0..x {
LL | |
LL | |
LL | |
...  |
LL | |         sum += i;
LL | |     }
   | |_____^

error[E0015]: calls in constant functions are limited to constant functions, tuple structs and tuple variants
  --> $DIR/const-fn-error.rs:5:14
   |
LL |     for i in 0..x {
   |              ^^^^

error[E0658]: mutable references are not allowed in constant functions
  --> $DIR/const-fn-error.rs:5:14
   |
LL |     for i in 0..x {
   |              ^^^^
   |
   = note: see issue #57349 <https://github.com/rust-lang/rust/issues/57349> for more information
   = help: add `#![feature(const_mut_refs)]` to the crate attributes to enable

error[E0015]: calls in constant functions are limited to constant functions, tuple structs and tuple variants
  --> $DIR/const-fn-error.rs:5:14
   |
LL |     for i in 0..x {
   |              ^^^^

error[E0080]: evaluation of constant value failed
  --> $DIR/const-fn-error.rs:5:14
   |
LL |     for i in 0..x {
   |              ^^^^
   |              |
   |              calling non-const function `<std::ops::Range<usize> as IntoIterator>::into_iter`
   |              inside `f` at $DIR/const-fn-error.rs:5:14
...
LL |     let a : [i32; f(X)];
   |                   ---- inside `main::{constant#0}` at $DIR/const-fn-error.rs:18:19

error: aborting due to 5 previous errors

Some errors have detailed explanations: E0015, E0080, E0658, E0744.
For more information about an error, try `rustc --explain E0015`.