--- /dev/null
+error[E0277]: the trait bound `[T; N]: Foo` is not satisfied
+ --> $DIR/const-param-placeholder.rs:17:17
+ |
+LL | needs_foo::<[T; N]>();
+ | ^^^^^^ the trait `Foo` is not implemented for `[T; N]`
+ |
+ = help: the trait `Foo` is implemented for `[T; 1]`
+note: required by a bound in `needs_foo`
+ --> $DIR/const-param-placeholder.rs:8:17
+ |
+LL | fn needs_foo<F: Foo>() {}
+ | ^^^ required by this bound in `needs_foo`
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0277`.