Auto merge of #90724 - JohnTitor:rollup-zg0kbm3, r=JohnTitor

Rollup of 6 pull requests

Successful merges:

 - #87530 (Add comments regarding superfluous `!Sync` impls)
 - #90591 (treat illumos like solaris in failing ui tests which need it)
 - #90678 (Add some GATs-related regression tests)
 - #90688 (enable `dotprod` target feature in arm)
 - #90708 (Add a note about feature(explicit_generic_args_with_impl_trait) to the relevant error message)
 - #90720 (Update cargo)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup

compiler/rustc_typeck/src/astconv/generics.rs

@@ -672,6 +672,17 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                 err.span_label(span, "explicit generic argument not allowed");
             }
 
+            err.note(
+                "see issue #83701 <https://github.com/rust-lang/rust/issues/83701> \
+                 for more information",
+            );
+            if tcx.sess.is_nightly_build() {
+                err.help(
+                    "add `#![feature(explicit_generic_args_with_impl_trait)]` \
+                     to the crate attributes to enable",
+                );
+            }
+
             err.emit();
         }