Auto merge of #105365 - matthiaskrgr:rollup-g0mrrt7, r=matthiaskrgr

Rollup of 11 pull requests

Successful merges:

 - #104439 (Add prototype to generate `COPYRIGHT` from REUSE metadata)
 - #105005 (On E0195 point at where clause lifetime bounds)
 - #105098 (propagate the error from parsing enum variant to the parser and emit out)
 - #105243 (remove no-op 'let _ = ')
 - #105254 (Recurse into nested impl-trait when computing variance.)
 - #105287 (Synthesize substitutions for bad auto traits in dyn types)
 - #105310 (Be more careful about unresolved exprs in suggestion)
 - #105318 (Make `get_impl_future_output_ty` work with AFIT)
 - #105339 (support `ConstKind::Expr` in `is_const_evaluatable` and `WfPredicates::compute`)
 - #105340 (Avoid ICE by accounting for missing type)
 - #105342 (Make `note_obligation_cause_code`  take a `impl ToPredicate` for predicate)

Failed merges:

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

2 files changed, 8 insertions, 1 deletions

diff --git a/compiler/rustc_parse/src/parser/item.rs b/compiler/rustc_parse/src/parser/item.rs
index 84c63219920..03f25392a7c 100644
--- a/compiler/rustc_parse/src/parser/item.rs
+++ b/compiler/rustc_parse/src/parser/item.rs
@@ -1414,7 +1414,10 @@ impl<'a> Parser<'a> {
 
                 Ok((Some(vr), TrailingToken::MaybeComma))
             },
-        )
+        ).map_err(|mut err|{
+            err.help("enum variants can be `Variant`, `Variant = <integer>`, `Variant(Type, ..., TypeN)` or `Variant { fields: Types }`");
+            err
+        })
     }
 
     /// Parses `struct Foo { ... }`.
diff --git a/compiler/rustc_parse/src/parser/mod.rs b/compiler/rustc_parse/src/parser/mod.rs
index 4d8bff28b05..bebb012660a 100644
--- a/compiler/rustc_parse/src/parser/mod.rs
+++ b/compiler/rustc_parse/src/parser/mod.rs
@@ -943,6 +943,10 @@ impl<'a> Parser<'a> {
                                 Err(e) => {
                                     // Parsing failed, therefore it must be something more serious
                                     // than just a missing separator.
+                                    for xx in &e.children {
+                                        // propagate the help message from sub error 'e' to main error 'expect_err;
+                                        expect_err.children.push(xx.clone());
+                                    }
                                     expect_err.emit();
 
                                     e.cancel();