error[E0283]: type annotations needed
  --> $DIR/issue-77982.rs:8:10
   |
LL |     opts.get(opt.as_ref());
   |          ^^^ ------------ this method call resolves to `&T`
   |          |
   |          cannot infer type for type parameter `Q` declared on the associated function `get`
   |
   = note: multiple `impl`s satisfying `String: Borrow<_>` found in the following crates: `alloc`, `core`:
           - impl Borrow<str> for String;
           - impl<T> Borrow<T> for T
             where T: ?Sized;
note: required by a bound in `HashMap::<K, V, S>::get`
  --> $SRC_DIR/std/src/collections/hash/map.rs:LL:COL
   |
LL |         K: Borrow<Q>,
   |            ^^^^^^^^^ required by this bound in `HashMap::<K, V, S>::get`
help: consider specifying the type argument in the function call
   |
LL |     opts.get::<Q>(opt.as_ref());
   |             +++++

error[E0283]: type annotations needed
  --> $DIR/issue-77982.rs:8:18
   |
LL |     opts.get(opt.as_ref());
   |              ----^^^^^^--
   |              |   |
   |              |   cannot infer type for type parameter `T` declared on the trait `AsRef`
   |              this method call resolves to `&T`
   |
   = note: multiple `impl`s satisfying `String: AsRef<_>` found in the following crates: `alloc`, `std`:
           - impl AsRef<OsStr> for String;
           - impl AsRef<Path> for String;
           - impl AsRef<[u8]> for String;
           - impl AsRef<str> for String;
help: use the fully qualified path for the potential candidates
   |
LL |     opts.get(<String as AsRef<OsStr>>::as_ref(opt));
   |              +++++++++++++++++++++++++++++++++   ~
LL |     opts.get(<String as AsRef<Path>>::as_ref(opt));
   |              ++++++++++++++++++++++++++++++++   ~
LL |     opts.get(<String as AsRef<[u8]>>::as_ref(opt));
   |              ++++++++++++++++++++++++++++++++   ~
LL |     opts.get(<String as AsRef<str>>::as_ref(opt));
   |              +++++++++++++++++++++++++++++++   ~
     and 4 other candidates

error[E0283]: type annotations needed
  --> $DIR/issue-77982.rs:13:44
   |
LL |     let ips: Vec<_> = (0..100_000).map(|_| u32::from(0u32.into())).collect();
   |                                            ^^^^^^^^^ ----------- this method call resolves to `T`
   |                                            |
   |                                            cannot infer type for type parameter `T` declared on the trait `From`
   |
   = note: multiple `impl`s satisfying `u32: From<_>` found in the following crates: `core`, `std`:
           - impl From<Ipv4Addr> for u32;
           - impl From<NonZeroU32> for u32;
           - impl From<bool> for u32;
           - impl From<char> for u32;
           and 3 more

error[E0283]: type annotations needed for `Box<T>`
  --> $DIR/issue-77982.rs:36:16
   |
LL |     let _ = ().foo();
   |         -      ^^^ cannot infer type for type parameter `T` declared on the trait `Foo`
   |         |
   |         consider giving this pattern the explicit type `Box<T>`, where the type parameter `T` is specified
   |
note: multiple `impl`s satisfying `(): Foo<'_, _>` found
  --> $DIR/issue-77982.rs:29:1
   |
LL | impl Foo<'static, u32> for () {}
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
LL | impl<'a> Foo<'a, i16> for () {}
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^

error[E0283]: type annotations needed for `Box<T>`
  --> $DIR/issue-77982.rs:40:19
   |
LL |     let _ = (&()).bar();
   |         -         ^^^ cannot infer type for type parameter `T` declared on the trait `Bar`
   |         |
   |         consider giving this pattern the explicit type `Box<T>`, where the type parameter `T` is specified
   |
note: multiple `impl`s satisfying `&(): Bar<'_, _>` found
  --> $DIR/issue-77982.rs:32:1
   |
LL | impl<'a> Bar<'static, u32> for &'a () {}
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
LL | impl<'a> Bar<'a, i16> for &'a () {}
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

error: aborting due to 5 previous errors

For more information about this error, try `rustc --explain E0283`.