Error messages wrt. patterns named the same as a type could be better

[Centril]

Given:

struct f; fn main() { let f = 1; }

a rust compiler (playground, stable) will error with:

error[E0308]: mismatched types
 --> src/main.rs:1:27
  |
1 | struct f; fn main() { let f = 1; }
  |                           ^ expected integral variable, found struct `f`
  |
  = note: expected type `{integer}`
             found type `f`

this is morally right; but the error message could highlight the fact that the user most likely confused the pattern f (as in the equivalent unit struct pattern f {}) with a variable binding f.

Tho, the names coinciding is somewhat pathological, so it might not warrant special care; but perhaps it does?

[estebank]

Duplicate of #48062.