tests/ui/autoref-autoderef/issue-38940.rs

   1 // issue-38940: error printed twice for deref recursion limit exceeded
   2 // Test that the recursion limit can be changed. In this case, we have
   3 // deeply nested types that will fail the `Send` check by overflow
   4 // when the recursion limit is set very low.
   5 // compile-flags: -Zdeduplicate-diagnostics=yes
   6
   7 #![allow(dead_code)]
   8 #![recursion_limit = "10"]
   9 macro_rules! link {
  10     ($outer:ident, $inner:ident) => {
  11         struct $outer($inner);
  12         impl $outer {
  13             fn new() -> $outer {
  14                 $outer($inner::new())
  15             }
  16         }
  17         impl std::ops::Deref for $outer {
  18             type Target = $inner;
  19             fn deref(&self) -> &$inner {
  20                 &self.0
  21             }
  22         }
  23     };
  24 }
  25
  26 struct Bottom;
  27
  28 impl Bottom {
  29     fn new() -> Bottom {
  30         Bottom
  31     }
  32 }
  33
  34 link!(Top, A);
  35 link!(A, B);
  36 link!(B, C);
  37 link!(C, D);
  38 link!(D, E);
  39 link!(E, F);
  40 link!(F, G);
  41 link!(G, H);
  42 link!(H, I);
  43 link!(I, J);
  44 link!(J, K);
  45 link!(K, Bottom);
  46
  47 fn main() {
  48     let t = Top::new();
  49     let x: &Bottom = &t;
  50     //~^ ERROR mismatched types
  51     //~| ERROR reached the recursion limit while auto-dereferencing `J`
  52 }