Auto merge of #101238 - RalfJung:rollup-bzcmobj, r=RalfJung

Rollup of 7 pull requests

Successful merges:

 - #90946 (Ignore `reference`s in "Type::inner_def_id")
 - #100730 (Migrate rustc_monomorphize to use SessionDiagnostic)
 - #100753 (translations(rustc_session): migrates `rustc_session` to use `SessionDiagnostic` - Pt. 1)
 - #100831 (Migrate `symbol_mangling` module to new diagnostics structs)
 - #101204 (rustdoc: Resugar async fn return type in `clean`, not `html`)
 - #101216 (Use in-page links for sanitizer docs.)
 - #101237 (fix into_iter on ZST)

Failed merges:

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

1 files changed, 7 insertions, 4 deletions

diff --git a/compiler/rustc_monomorphize/src/polymorphize.rs b/compiler/rustc_monomorphize/src/polymorphize.rs
index 394843e510d..6e4ab2a35c3 100644
--- a/compiler/rustc_monomorphize/src/polymorphize.rs
+++ b/compiler/rustc_monomorphize/src/polymorphize.rs
@@ -22,6 +22,8 @@ use rustc_span::symbol::sym;
 use std::convert::TryInto;
 use std::ops::ControlFlow;
 
+use crate::errors::UnusedGenericParams;
+
 /// Provide implementations of queries relating to polymorphization analysis.
 pub fn provide(providers: &mut Providers) {
     providers.unused_generic_params = unused_generic_params;
@@ -206,22 +208,23 @@ fn emit_unused_generic_params_error<'tcx>(
         _ => tcx.def_span(def_id),
     };
 
-    let mut err = tcx.sess.struct_span_err(fn_span, "item has unused generic parameters");
-
+    let mut param_spans = Vec::new();
+    let mut param_names = Vec::new();
     let mut next_generics = Some(generics);
     while let Some(generics) = next_generics {
         for param in &generics.params {
             if unused_parameters.contains(param.index).unwrap_or(false) {
                 debug!(?param);
                 let def_span = tcx.def_span(param.def_id);
-                err.span_label(def_span, &format!("generic parameter `{}` is unused", param.name));
+                param_spans.push(def_span);
+                param_names.push(param.name.to_string());
             }
         }
 
         next_generics = generics.parent.map(|did| tcx.generics_of(did));
     }
 
-    err.emit();
+    tcx.sess.emit_err(UnusedGenericParams { span: fn_span, param_spans, param_names });
 }
 
 /// Visitor used to aggregate generic parameter uses.