87 files changed, 153 insertions, 10 deletions

diff --git a/src/test/ui/inference/ambiguous_type_parameter.rs b/tests/ui/inference/ambiguous_type_parameter.rs
index dc70ed661..dc70ed661 100644
--- a/src/test/ui/inference/ambiguous_type_parameter.rs
+++ b/tests/ui/inference/ambiguous_type_parameter.rs
diff --git a/src/test/ui/inference/ambiguous_type_parameter.stderr b/tests/ui/inference/ambiguous_type_parameter.stderr
index 9cbe221de..9cbe221de 100644
--- a/src/test/ui/inference/ambiguous_type_parameter.stderr
+++ b/tests/ui/inference/ambiguous_type_parameter.stderr
diff --git a/src/test/ui/inference/auxiliary/inference_unstable_iterator.rs b/tests/ui/inference/auxiliary/inference_unstable_iterator.rs
index 04bc0b1a8..04bc0b1a8 100644
--- a/src/test/ui/inference/auxiliary/inference_unstable_iterator.rs
+++ b/tests/ui/inference/auxiliary/inference_unstable_iterator.rs
diff --git a/src/test/ui/inference/auxiliary/inference_unstable_itertools.rs b/tests/ui/inference/auxiliary/inference_unstable_itertools.rs
index fa1efbcfe..fa1efbcfe 100644
--- a/src/test/ui/inference/auxiliary/inference_unstable_itertools.rs
+++ b/tests/ui/inference/auxiliary/inference_unstable_itertools.rs
diff --git a/src/test/ui/inference/cannot-infer-async.rs b/tests/ui/inference/cannot-infer-async.rs
index b5152d04f..b5152d04f 100644
--- a/src/test/ui/inference/cannot-infer-async.rs
+++ b/tests/ui/inference/cannot-infer-async.rs
diff --git a/src/test/ui/inference/cannot-infer-async.stderr b/tests/ui/inference/cannot-infer-async.stderr
index 0579cf238..0579cf238 100644
--- a/src/test/ui/inference/cannot-infer-async.stderr
+++ b/tests/ui/inference/cannot-infer-async.stderr
diff --git a/src/test/ui/inference/cannot-infer-closure-circular.rs b/tests/ui/inference/cannot-infer-closure-circular.rs
index affb48149..affb48149 100644
--- a/src/test/ui/inference/cannot-infer-closure-circular.rs
+++ b/tests/ui/inference/cannot-infer-closure-circular.rs
diff --git a/src/test/ui/inference/cannot-infer-closure-circular.stderr b/tests/ui/inference/cannot-infer-closure-circular.stderr
index b706cd2bc..b706cd2bc 100644
--- a/src/test/ui/inference/cannot-infer-closure-circular.stderr
+++ b/tests/ui/inference/cannot-infer-closure-circular.stderr
diff --git a/src/test/ui/inference/cannot-infer-closure.rs b/tests/ui/inference/cannot-infer-closure.rs
index bd5d10b41..bd5d10b41 100644
--- a/src/test/ui/inference/cannot-infer-closure.rs
+++ b/tests/ui/inference/cannot-infer-closure.rs
diff --git a/src/test/ui/inference/cannot-infer-closure.stderr b/tests/ui/inference/cannot-infer-closure.stderr
index a4b818e6e..a4b818e6e 100644
--- a/src/test/ui/inference/cannot-infer-closure.stderr
+++ b/tests/ui/inference/cannot-infer-closure.stderr
diff --git a/src/test/ui/inference/cannot-infer-partial-try-return.rs b/tests/ui/inference/cannot-infer-partial-try-return.rs
index b555697dc..b555697dc 100644
--- a/src/test/ui/inference/cannot-infer-partial-try-return.rs
+++ b/tests/ui/inference/cannot-infer-partial-try-return.rs
diff --git a/src/test/ui/inference/cannot-infer-partial-try-return.stderr b/tests/ui/inference/cannot-infer-partial-try-return.stderr
index 2a56aaa44..888c321bc 100644
--- a/src/test/ui/inference/cannot-infer-partial-try-return.stderr
+++ b/tests/ui/inference/cannot-infer-partial-try-return.stderr
@@ -1,8 +1,6 @@
 error[E0282]: type annotations needed
   --> $DIR/cannot-infer-partial-try-return.rs:20:9
    |
-LL |         infallible()?;
-   |         ------------- type must be known at this point
 LL |         Ok(())
    |         ^^ cannot infer type of the type parameter `E` declared on the enum `Result`
    |
diff --git a/src/test/ui/inference/char-as-str-multi.rs b/tests/ui/inference/char-as-str-multi.rs
index c29a15025..c29a15025 100644
--- a/src/test/ui/inference/char-as-str-multi.rs
+++ b/tests/ui/inference/char-as-str-multi.rs
diff --git a/src/test/ui/inference/char-as-str-multi.stderr b/tests/ui/inference/char-as-str-multi.stderr
index 297ca2b54..297ca2b54 100644
--- a/src/test/ui/inference/char-as-str-multi.stderr
+++ b/tests/ui/inference/char-as-str-multi.stderr
diff --git a/src/test/ui/inference/char-as-str-single.fixed b/tests/ui/inference/char-as-str-single.fixed
index bab1854dc..bab1854dc 100644
--- a/src/test/ui/inference/char-as-str-single.fixed
+++ b/tests/ui/inference/char-as-str-single.fixed
diff --git a/src/test/ui/inference/char-as-str-single.rs b/tests/ui/inference/char-as-str-single.rs
index 736920643..736920643 100644
--- a/src/test/ui/inference/char-as-str-single.rs
+++ b/tests/ui/inference/char-as-str-single.rs
diff --git a/src/test/ui/inference/char-as-str-single.stderr b/tests/ui/inference/char-as-str-single.stderr
index 3375ec6ac..3375ec6ac 100644
--- a/src/test/ui/inference/char-as-str-single.stderr
+++ b/tests/ui/inference/char-as-str-single.stderr
diff --git a/src/test/ui/inference/deref-suggestion.rs b/tests/ui/inference/deref-suggestion.rs
index 0d8e7289d..0d8e7289d 100644
--- a/src/test/ui/inference/deref-suggestion.rs
+++ b/tests/ui/inference/deref-suggestion.rs
diff --git a/src/test/ui/inference/deref-suggestion.stderr b/tests/ui/inference/deref-suggestion.stderr
index 034005697..3db67cdb5 100644
--- a/src/test/ui/inference/deref-suggestion.stderr
+++ b/tests/ui/inference/deref-suggestion.stderr
@@ -87,7 +87,10 @@ error[E0308]: mismatched types
   --> $DIR/deref-suggestion.rs:37:5
    |
 LL |     assert_eq!(3i32, &3i32);
-   |     ^^^^^^^^^^^^^^^^^^^^^^^ expected `i32`, found `&i32`
+   |     ^^^^^^^^^^^^^^^^^^^^^^^
+   |     |
+   |     expected `i32`, found `&i32`
+   |     expected because this is `i32`
    |
    = note: this error originates in the macro `assert_eq` (in Nightly builds, run with -Z macro-backtrace for more info)
 
diff --git a/src/test/ui/inference/erase-type-params-in-label.rs b/tests/ui/inference/erase-type-params-in-label.rs
index 1fea2da92..1fea2da92 100644
--- a/src/test/ui/inference/erase-type-params-in-label.rs
+++ b/tests/ui/inference/erase-type-params-in-label.rs
diff --git a/tests/ui/inference/erase-type-params-in-label.stderr b/tests/ui/inference/erase-type-params-in-label.stderr
new file mode 100644
index 000000000..9be182864
--- /dev/null
+++ b/tests/ui/inference/erase-type-params-in-label.stderr
@@ -0,0 +1,37 @@
+error[E0283]: type annotations needed for `Foo<i32, &str, W, Z>`
+  --> $DIR/erase-type-params-in-label.rs:2:9
+   |
+LL |     let foo = foo(1, "");
+   |         ^^^   --- type must be known at this point
+   |
+   = note: cannot satisfy `_: Default`
+note: required by a bound in `foo`
+  --> $DIR/erase-type-params-in-label.rs:25:17
+   |
+LL | fn foo<T, K, W: Default, Z: Default>(t: T, k: K) -> Foo<T, K, W, Z> {
+   |                 ^^^^^^^ required by this bound in `foo`
+help: consider giving `foo` an explicit type, where the type for type parameter `W` is specified
+   |
+LL |     let foo: Foo<i32, &str, W, Z> = foo(1, "");
+   |            ++++++++++++++++++++++
+
+error[E0283]: type annotations needed for `Bar<i32, &str, Z>`
+  --> $DIR/erase-type-params-in-label.rs:5:9
+   |
+LL |     let bar = bar(1, "");
+   |         ^^^   --- type must be known at this point
+   |
+   = note: cannot satisfy `_: Default`
+note: required by a bound in `bar`
+  --> $DIR/erase-type-params-in-label.rs:14:17
+   |
+LL | fn bar<T, K, Z: Default>(t: T, k: K) -> Bar<T, K, Z> {
+   |                 ^^^^^^^ required by this bound in `bar`
+help: consider giving `bar` an explicit type, where the type for type parameter `Z` is specified
+   |
+LL |     let bar: Bar<i32, &str, Z> = bar(1, "");
+   |            +++++++++++++++++++
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0283`.
diff --git a/src/test/ui/inference/infer-binary-operand-behind-reference.rs b/tests/ui/inference/infer-binary-operand-behind-reference.rs
index 0c0a3171e..0c0a3171e 100644
--- a/src/test/ui/inference/infer-binary-operand-behind-reference.rs
+++ b/tests/ui/inference/infer-binary-operand-behind-reference.rs
diff --git a/src/test/ui/inference/inference-variable-behind-raw-pointer.rs b/tests/ui/inference/inference-variable-behind-raw-pointer.rs
index 6662e46b1..6662e46b1 100644
--- a/src/test/ui/inference/inference-variable-behind-raw-pointer.rs
+++ b/tests/ui/inference/inference-variable-behind-raw-pointer.rs
diff --git a/src/test/ui/inference/inference-variable-behind-raw-pointer.stderr b/tests/ui/inference/inference-variable-behind-raw-pointer.stderr
index 3dea09e7f..3dea09e7f 100644
--- a/src/test/ui/inference/inference-variable-behind-raw-pointer.stderr
+++ b/tests/ui/inference/inference-variable-behind-raw-pointer.stderr
diff --git a/src/test/ui/inference/inference_unstable.rs b/tests/ui/inference/inference_unstable.rs
index daf0cf042..daf0cf042 100644
--- a/src/test/ui/inference/inference_unstable.rs
+++ b/tests/ui/inference/inference_unstable.rs
diff --git a/src/test/ui/inference/inference_unstable.stderr b/tests/ui/inference/inference_unstable.stderr
index ecbf2641b..ecbf2641b 100644
--- a/src/test/ui/inference/inference_unstable.stderr
+++ b/tests/ui/inference/inference_unstable.stderr
diff --git a/src/test/ui/inference/inference_unstable_featured.rs b/tests/ui/inference/inference_unstable_featured.rs
index 792b29aaa..792b29aaa 100644
--- a/src/test/ui/inference/inference_unstable_featured.rs
+++ b/tests/ui/inference/inference_unstable_featured.rs
diff --git a/src/test/ui/inference/inference_unstable_featured.stderr b/tests/ui/inference/inference_unstable_featured.stderr
index 4ddede29c..4ddede29c 100644
--- a/src/test/ui/inference/inference_unstable_featured.stderr
+++ b/tests/ui/inference/inference_unstable_featured.stderr
diff --git a/src/test/ui/inference/inference_unstable_forced.rs b/tests/ui/inference/inference_unstable_forced.rs
index 649b3ed2a..649b3ed2a 100644
--- a/src/test/ui/inference/inference_unstable_forced.rs
+++ b/tests/ui/inference/inference_unstable_forced.rs
diff --git a/src/test/ui/inference/inference_unstable_forced.stderr b/tests/ui/inference/inference_unstable_forced.stderr
index a1c4cd851..a1c4cd851 100644
--- a/src/test/ui/inference/inference_unstable_forced.stderr
+++ b/tests/ui/inference/inference_unstable_forced.stderr
diff --git a/src/test/ui/inference/issue-103587.rs b/tests/ui/inference/issue-103587.rs
index 11536f9f4..11536f9f4 100644
--- a/src/test/ui/inference/issue-103587.rs
+++ b/tests/ui/inference/issue-103587.rs
diff --git a/src/test/ui/inference/issue-103587.stderr b/tests/ui/inference/issue-103587.stderr
index b373fbfbb..b373fbfbb 100644
--- a/src/test/ui/inference/issue-103587.stderr
+++ b/tests/ui/inference/issue-103587.stderr
diff --git a/src/test/ui/inference/issue-104649.rs b/tests/ui/inference/issue-104649.rs
index 4637b884d..4637b884d 100644
--- a/src/test/ui/inference/issue-104649.rs
+++ b/tests/ui/inference/issue-104649.rs
diff --git a/src/test/ui/inference/issue-104649.stderr b/tests/ui/inference/issue-104649.stderr
index 4962b21f9..4962b21f9 100644
--- a/src/test/ui/inference/issue-104649.stderr
+++ b/tests/ui/inference/issue-104649.stderr
diff --git a/src/test/ui/inference/issue-28935.rs b/tests/ui/inference/issue-28935.rs
index 872822dbd..872822dbd 100644
--- a/src/test/ui/inference/issue-28935.rs
+++ b/tests/ui/inference/issue-28935.rs
diff --git a/src/test/ui/inference/issue-36053.rs b/tests/ui/inference/issue-36053.rs
index 5c6d07804..5c6d07804 100644
--- a/src/test/ui/inference/issue-36053.rs
+++ b/tests/ui/inference/issue-36053.rs
diff --git a/src/test/ui/inference/issue-70703.rs b/tests/ui/inference/issue-70703.rs
index d90498e96..d90498e96 100644
--- a/src/test/ui/inference/issue-70703.rs
+++ b/tests/ui/inference/issue-70703.rs
diff --git a/src/test/ui/inference/issue-71309.rs b/tests/ui/inference/issue-71309.rs
index c31107d8f..c31107d8f 100644
--- a/src/test/ui/inference/issue-71309.rs
+++ b/tests/ui/inference/issue-71309.rs
diff --git a/src/test/ui/inference/issue-71309.stderr b/tests/ui/inference/issue-71309.stderr
index af8714f1c..af8714f1c 100644
--- a/src/test/ui/inference/issue-71309.stderr
+++ b/tests/ui/inference/issue-71309.stderr
diff --git a/src/test/ui/inference/issue-71732.rs b/tests/ui/inference/issue-71732.rs
index 8a9d2b235..8a9d2b235 100644
--- a/src/test/ui/inference/issue-71732.rs
+++ b/tests/ui/inference/issue-71732.rs
diff --git a/src/test/ui/inference/issue-71732.stderr b/tests/ui/inference/issue-71732.stderr
index 79bee3328..01b37f2ac 100644
--- a/src/test/ui/inference/issue-71732.stderr
+++ b/tests/ui/inference/issue-71732.stderr
@@ -12,9 +12,6 @@ LL |         .get(&"key".into())
              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 generic argument
    |
 LL |         .get::<Q>(&"key".into())
diff --git a/src/test/ui/inference/issue-72616.rs b/tests/ui/inference/issue-72616.rs
index 69ade1a75..69ade1a75 100644
--- a/src/test/ui/inference/issue-72616.rs
+++ b/tests/ui/inference/issue-72616.rs
diff --git a/src/test/ui/inference/issue-72616.stderr b/tests/ui/inference/issue-72616.stderr
index 6ee0626ca..6ee0626ca 100644
--- a/src/test/ui/inference/issue-72616.stderr
+++ b/tests/ui/inference/issue-72616.stderr
diff --git a/src/test/ui/inference/issue-72690.rs b/tests/ui/inference/issue-72690.rs
index 8c0a0f51a..8c0a0f51a 100644
--- a/src/test/ui/inference/issue-72690.rs
+++ b/tests/ui/inference/issue-72690.rs
diff --git a/src/test/ui/inference/issue-72690.stderr b/tests/ui/inference/issue-72690.stderr
index d4eeda073..8eda71ec0 100644
--- a/src/test/ui/inference/issue-72690.stderr
+++ b/tests/ui/inference/issue-72690.stderr
@@ -32,8 +32,8 @@ LL |     |x| String::from("x".as_ref());
    |
 help: consider giving this closure parameter an explicit type
    |
-LL |     |x: _| String::from("x".as_ref());
-   |       +++
+LL |     |x: /* Type */| String::from("x".as_ref());
+   |       ++++++++++++
 
 error[E0283]: type annotations needed
   --> $DIR/issue-72690.rs:12:26
diff --git a/tests/ui/inference/issue-80816.rs b/tests/ui/inference/issue-80816.rs
new file mode 100644
index 000000000..4d319b449
--- /dev/null
+++ b/tests/ui/inference/issue-80816.rs
@@ -0,0 +1,55 @@
+#![allow(unreachable_code)]
+
+use std::marker::PhantomData;
+use std::ops::Deref;
+use std::sync::Arc;
+
+pub struct Guard<T> {
+    _phantom: PhantomData<T>,
+}
+impl<T> Deref for Guard<T> {
+    type Target = T;
+    fn deref(&self) -> &T {
+        unimplemented!()
+    }
+}
+
+pub struct DirectDeref<T>(T);
+impl<T> Deref for DirectDeref<Arc<T>> {
+    type Target = T;
+    fn deref(&self) -> &T {
+        unimplemented!()
+    }
+}
+
+pub trait Access<T> {
+    type Guard: Deref<Target = T>;
+    fn load(&self) -> Self::Guard {
+        unimplemented!()
+    }
+}
+impl<T, A: Access<T>, P: Deref<Target = A>> Access<T> for P {
+    //~^ NOTE: required for `Arc<ArcSwapAny<Arc<usize>>>` to implement `Access<_>`
+    //~| NOTE unsatisfied trait bound introduced here
+    type Guard = A::Guard;
+}
+impl<T> Access<T> for ArcSwapAny<T> {
+    //~^ NOTE: multiple `impl`s satisfying `ArcSwapAny<Arc<usize>>: Access<_>` found
+    type Guard = Guard<T>;
+}
+impl<T> Access<T> for ArcSwapAny<Arc<T>> {
+    type Guard = DirectDeref<Arc<T>>;
+}
+
+pub struct ArcSwapAny<T> {
+    _phantom_arc: PhantomData<T>,
+}
+
+pub fn foo() {
+    let s: Arc<ArcSwapAny<Arc<usize>>> = unimplemented!();
+    let guard: Guard<Arc<usize>> = s.load();
+    //~^ ERROR: type annotations needed
+    //~| HELP: try using a fully qualified path to specify the expected types
+}
+
+fn main() {}
diff --git a/tests/ui/inference/issue-80816.stderr b/tests/ui/inference/issue-80816.stderr
new file mode 100644
index 000000000..80c0c8abe
--- /dev/null
+++ b/tests/ui/inference/issue-80816.stderr
@@ -0,0 +1,29 @@
+error[E0283]: type annotations needed
+  --> $DIR/issue-80816.rs:50:38
+   |
+LL |     let guard: Guard<Arc<usize>> = s.load();
+   |                                      ^^^^
+   |
+note: multiple `impl`s satisfying `ArcSwapAny<Arc<usize>>: Access<_>` found
+  --> $DIR/issue-80816.rs:36:1
+   |
+LL | impl<T> Access<T> for ArcSwapAny<T> {
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+...
+LL | impl<T> Access<T> for ArcSwapAny<Arc<T>> {
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+note: required for `Arc<ArcSwapAny<Arc<usize>>>` to implement `Access<_>`
+  --> $DIR/issue-80816.rs:31:45
+   |
+LL | impl<T, A: Access<T>, P: Deref<Target = A>> Access<T> for P {
+   |            ---------                        ^^^^^^^^^     ^
+   |            |
+   |            unsatisfied trait bound introduced here
+help: try using a fully qualified path to specify the expected types
+   |
+LL |     let guard: Guard<Arc<usize>> = <Arc<ArcSwapAny<Arc<usize>>> as Access<T>>::load(&s);
+   |                                    ++++++++++++++++++++++++++++++++++++++++++++++++++ ~
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0283`.
diff --git a/src/test/ui/inference/issue-81522.rs b/tests/ui/inference/issue-81522.rs
index 902f8fdde..902f8fdde 100644
--- a/src/test/ui/inference/issue-81522.rs
+++ b/tests/ui/inference/issue-81522.rs
diff --git a/tests/ui/inference/issue-83606.rs b/tests/ui/inference/issue-83606.rs
new file mode 100644
index 000000000..c387046e9
--- /dev/null
+++ b/tests/ui/inference/issue-83606.rs
@@ -0,0 +1,10 @@
+// Regression test for #83606.
+
+fn foo<const N: usize>(_: impl std::fmt::Display) -> [usize; N] {
+    [0; N]
+}
+
+fn main() {
+    let _ = foo("foo");
+    //~^ ERROR: type annotations needed for `[usize; N]`
+}
diff --git a/src/test/ui/inference/issue-83606.stderr b/tests/ui/inference/issue-83606.stderr
index f5c84f960..f2ee8692e 100644
--- a/src/test/ui/inference/issue-83606.stderr
+++ b/tests/ui/inference/issue-83606.stderr
@@ -1,4 +1,4 @@
-error[E0282]: type annotations needed for `[usize; _]`
+error[E0282]: type annotations needed for `[usize; N]`
   --> $DIR/issue-83606.rs:8:9
    |
 LL |     let _ = foo("foo");
@@ -6,7 +6,7 @@ LL |     let _ = foo("foo");
    |
 help: consider giving this pattern a type, where the the value of const parameter `N` is specified
    |
-LL |     let _: [usize; _] = foo("foo");
+LL |     let _: [usize; N] = foo("foo");
    |          ++++++++++++
 
 error: aborting due to previous error
diff --git a/src/test/ui/inference/issue-86162-1.rs b/tests/ui/inference/issue-86162-1.rs
index 5a547eb38..5a547eb38 100644
--- a/src/test/ui/inference/issue-86162-1.rs
+++ b/tests/ui/inference/issue-86162-1.rs
diff --git a/src/test/ui/inference/issue-86162-1.stderr b/tests/ui/inference/issue-86162-1.stderr
index 4f621b82d..4f621b82d 100644
--- a/src/test/ui/inference/issue-86162-1.stderr
+++ b/tests/ui/inference/issue-86162-1.stderr
diff --git a/src/test/ui/inference/issue-86162-2.rs b/tests/ui/inference/issue-86162-2.rs
index b8c75dd77..b8c75dd77 100644
--- a/src/test/ui/inference/issue-86162-2.rs
+++ b/tests/ui/inference/issue-86162-2.rs
diff --git a/src/test/ui/inference/issue-86162-2.stderr b/tests/ui/inference/issue-86162-2.stderr
index 9aff2cec1..9aff2cec1 100644
--- a/src/test/ui/inference/issue-86162-2.stderr
+++ b/tests/ui/inference/issue-86162-2.stderr
diff --git a/src/test/ui/inference/lub-glb-with-unbound-infer-var.rs b/tests/ui/inference/lub-glb-with-unbound-infer-var.rs
index c9e117089..c9e117089 100644
--- a/src/test/ui/inference/lub-glb-with-unbound-infer-var.rs
+++ b/tests/ui/inference/lub-glb-with-unbound-infer-var.rs
diff --git a/src/test/ui/inference/need_type_info/channel.rs b/tests/ui/inference/need_type_info/channel.rs
index e2ba5a941..e2ba5a941 100644
--- a/src/test/ui/inference/need_type_info/channel.rs
+++ b/tests/ui/inference/need_type_info/channel.rs
diff --git a/src/test/ui/inference/need_type_info/channel.stderr b/tests/ui/inference/need_type_info/channel.stderr
index e33ace033..e33ace033 100644
--- a/src/test/ui/inference/need_type_info/channel.stderr
+++ b/tests/ui/inference/need_type_info/channel.stderr
diff --git a/src/test/ui/inference/need_type_info/concrete-impl.rs b/tests/ui/inference/need_type_info/concrete-impl.rs
index 72e0e74f3..72e0e74f3 100644
--- a/src/test/ui/inference/need_type_info/concrete-impl.rs
+++ b/tests/ui/inference/need_type_info/concrete-impl.rs
diff --git a/src/test/ui/inference/need_type_info/concrete-impl.stderr b/tests/ui/inference/need_type_info/concrete-impl.stderr
index aa3296995..aa3296995 100644
--- a/src/test/ui/inference/need_type_info/concrete-impl.stderr
+++ b/tests/ui/inference/need_type_info/concrete-impl.stderr
diff --git a/src/test/ui/inference/need_type_info/do-not-suggest-generic-arguments-for-turbofish.rs b/tests/ui/inference/need_type_info/do-not-suggest-generic-arguments-for-turbofish.rs
index 3084f6eac..3084f6eac 100644
--- a/src/test/ui/inference/need_type_info/do-not-suggest-generic-arguments-for-turbofish.rs
+++ b/tests/ui/inference/need_type_info/do-not-suggest-generic-arguments-for-turbofish.rs
diff --git a/src/test/ui/inference/need_type_info/do-not-suggest-generic-arguments-for-turbofish.stderr b/tests/ui/inference/need_type_info/do-not-suggest-generic-arguments-for-turbofish.stderr
index 2ad35ab03..2ad35ab03 100644
--- a/src/test/ui/inference/need_type_info/do-not-suggest-generic-arguments-for-turbofish.stderr
+++ b/tests/ui/inference/need_type_info/do-not-suggest-generic-arguments-for-turbofish.stderr
diff --git a/src/test/ui/inference/need_type_info/expr-struct-type-relative-enum.rs b/tests/ui/inference/need_type_info/expr-struct-type-relative-enum.rs
index 42af9fa8d..42af9fa8d 100644
--- a/src/test/ui/inference/need_type_info/expr-struct-type-relative-enum.rs
+++ b/tests/ui/inference/need_type_info/expr-struct-type-relative-enum.rs
diff --git a/src/test/ui/inference/need_type_info/expr-struct-type-relative-enum.stderr b/tests/ui/inference/need_type_info/expr-struct-type-relative-enum.stderr
index 68ecb3813..68ecb3813 100644
--- a/src/test/ui/inference/need_type_info/expr-struct-type-relative-enum.stderr
+++ b/tests/ui/inference/need_type_info/expr-struct-type-relative-enum.stderr
diff --git a/src/test/ui/inference/need_type_info/expr-struct-type-relative-gat.rs b/tests/ui/inference/need_type_info/expr-struct-type-relative-gat.rs
index b0c0d3397..b0c0d3397 100644
--- a/src/test/ui/inference/need_type_info/expr-struct-type-relative-gat.rs
+++ b/tests/ui/inference/need_type_info/expr-struct-type-relative-gat.rs
diff --git a/src/test/ui/inference/need_type_info/expr-struct-type-relative-gat.stderr b/tests/ui/inference/need_type_info/expr-struct-type-relative-gat.stderr
index cbc2477de..cbc2477de 100644
--- a/src/test/ui/inference/need_type_info/expr-struct-type-relative-gat.stderr
+++ b/tests/ui/inference/need_type_info/expr-struct-type-relative-gat.stderr
diff --git a/src/test/ui/inference/need_type_info/expr-struct-type-relative.rs b/tests/ui/inference/need_type_info/expr-struct-type-relative.rs
index c3ece2b16..c3ece2b16 100644
--- a/src/test/ui/inference/need_type_info/expr-struct-type-relative.rs
+++ b/tests/ui/inference/need_type_info/expr-struct-type-relative.rs
diff --git a/src/test/ui/inference/need_type_info/expr-struct-type-relative.stderr b/tests/ui/inference/need_type_info/expr-struct-type-relative.stderr
index 397d8e7be..397d8e7be 100644
--- a/src/test/ui/inference/need_type_info/expr-struct-type-relative.stderr
+++ b/tests/ui/inference/need_type_info/expr-struct-type-relative.stderr
diff --git a/src/test/ui/inference/need_type_info/issue-103053.rs b/tests/ui/inference/need_type_info/issue-103053.rs
index 05169666f..05169666f 100644
--- a/src/test/ui/inference/need_type_info/issue-103053.rs
+++ b/tests/ui/inference/need_type_info/issue-103053.rs
diff --git a/src/test/ui/inference/need_type_info/issue-103053.stderr b/tests/ui/inference/need_type_info/issue-103053.stderr
index 84f0475d8..84f0475d8 100644
--- a/src/test/ui/inference/need_type_info/issue-103053.stderr
+++ b/tests/ui/inference/need_type_info/issue-103053.stderr
diff --git a/src/test/ui/inference/need_type_info/self-ty-in-path.rs b/tests/ui/inference/need_type_info/self-ty-in-path.rs
index 768a8cc37..768a8cc37 100644
--- a/src/test/ui/inference/need_type_info/self-ty-in-path.rs
+++ b/tests/ui/inference/need_type_info/self-ty-in-path.rs
diff --git a/src/test/ui/inference/need_type_info/self-ty-in-path.stderr b/tests/ui/inference/need_type_info/self-ty-in-path.stderr
index 04b521dbd..04b521dbd 100644
--- a/src/test/ui/inference/need_type_info/self-ty-in-path.stderr
+++ b/tests/ui/inference/need_type_info/self-ty-in-path.stderr
diff --git a/src/test/ui/inference/need_type_info/type-alias-indirect.rs b/tests/ui/inference/need_type_info/type-alias-indirect.rs
index 0ed02ddc5..0ed02ddc5 100644
--- a/src/test/ui/inference/need_type_info/type-alias-indirect.rs
+++ b/tests/ui/inference/need_type_info/type-alias-indirect.rs
diff --git a/src/test/ui/inference/need_type_info/type-alias-indirect.stderr b/tests/ui/inference/need_type_info/type-alias-indirect.stderr
index 6161690df..6161690df 100644
--- a/src/test/ui/inference/need_type_info/type-alias-indirect.stderr
+++ b/tests/ui/inference/need_type_info/type-alias-indirect.stderr
diff --git a/src/test/ui/inference/need_type_info/type-alias.rs b/tests/ui/inference/need_type_info/type-alias.rs
index f921b046b..f921b046b 100644
--- a/src/test/ui/inference/need_type_info/type-alias.rs
+++ b/tests/ui/inference/need_type_info/type-alias.rs
diff --git a/src/test/ui/inference/need_type_info/type-alias.stderr b/tests/ui/inference/need_type_info/type-alias.stderr
index a33f49baf..a33f49baf 100644
--- a/src/test/ui/inference/need_type_info/type-alias.stderr
+++ b/tests/ui/inference/need_type_info/type-alias.stderr
diff --git a/src/test/ui/inference/newlambdas-ret-infer.rs b/tests/ui/inference/newlambdas-ret-infer.rs
index 9b629838f..9b629838f 100644
--- a/src/test/ui/inference/newlambdas-ret-infer.rs
+++ b/tests/ui/inference/newlambdas-ret-infer.rs
diff --git a/src/test/ui/inference/newlambdas-ret-infer2.rs b/tests/ui/inference/newlambdas-ret-infer2.rs
index abe31a05f..abe31a05f 100644
--- a/src/test/ui/inference/newlambdas-ret-infer2.rs
+++ b/tests/ui/inference/newlambdas-ret-infer2.rs
diff --git a/src/test/ui/inference/question-mark-type-infer.rs b/tests/ui/inference/question-mark-type-infer.rs
index 10560f85e..10560f85e 100644
--- a/src/test/ui/inference/question-mark-type-infer.rs
+++ b/tests/ui/inference/question-mark-type-infer.rs
diff --git a/tests/ui/inference/question-mark-type-infer.stderr b/tests/ui/inference/question-mark-type-infer.stderr
new file mode 100644
index 000000000..a9cb7e525
--- /dev/null
+++ b/tests/ui/inference/question-mark-type-infer.stderr
@@ -0,0 +1,14 @@
+error[E0282]: type annotations needed
+  --> $DIR/question-mark-type-infer.rs:10:21
+   |
+LL |     l.iter().map(f).collect()?
+   |                     ^^^^^^^ cannot infer type of the type parameter `B` declared on the associated function `collect`
+   |
+help: consider specifying the generic argument
+   |
+LL |     l.iter().map(f).collect::<Vec<_>>()?
+   |                            ++++++++++
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0282`.
diff --git a/src/test/ui/inference/range-type-infer.rs b/tests/ui/inference/range-type-infer.rs
index f07c04171..f07c04171 100644
--- a/src/test/ui/inference/range-type-infer.rs
+++ b/tests/ui/inference/range-type-infer.rs
diff --git a/src/test/ui/inference/simple-infer.rs b/tests/ui/inference/simple-infer.rs
index 561e4fdec..561e4fdec 100644
--- a/src/test/ui/inference/simple-infer.rs
+++ b/tests/ui/inference/simple-infer.rs
diff --git a/src/test/ui/inference/str-as-char.fixed b/tests/ui/inference/str-as-char.fixed
index 6aea809cb..6aea809cb 100644
--- a/src/test/ui/inference/str-as-char.fixed
+++ b/tests/ui/inference/str-as-char.fixed
diff --git a/src/test/ui/inference/str-as-char.rs b/tests/ui/inference/str-as-char.rs
index eaa8d788c..eaa8d788c 100644
--- a/src/test/ui/inference/str-as-char.rs
+++ b/tests/ui/inference/str-as-char.rs
diff --git a/src/test/ui/inference/str-as-char.stderr b/tests/ui/inference/str-as-char.stderr
index 2c84dac8e..2c84dac8e 100644
--- a/src/test/ui/inference/str-as-char.stderr
+++ b/tests/ui/inference/str-as-char.stderr
diff --git a/src/test/ui/inference/tutorial-suffix-inference-test.rs b/tests/ui/inference/tutorial-suffix-inference-test.rs
index 849adfd53..849adfd53 100644
--- a/src/test/ui/inference/tutorial-suffix-inference-test.rs
+++ b/tests/ui/inference/tutorial-suffix-inference-test.rs
diff --git a/src/test/ui/inference/tutorial-suffix-inference-test.stderr b/tests/ui/inference/tutorial-suffix-inference-test.stderr
index d83a1367d..d83a1367d 100644
--- a/src/test/ui/inference/tutorial-suffix-inference-test.stderr
+++ b/tests/ui/inference/tutorial-suffix-inference-test.stderr
diff --git a/src/test/ui/inference/type-infer-generalize-ty-var.rs b/tests/ui/inference/type-infer-generalize-ty-var.rs
index a3d6916cb..a3d6916cb 100644
--- a/src/test/ui/inference/type-infer-generalize-ty-var.rs
+++ b/tests/ui/inference/type-infer-generalize-ty-var.rs