Store a `Symbol` instead of an `Ident` in `VariantDef`/`FieldDef`

The field is also renamed from `ident` to `name. In most cases,
we don't actually need the `Span`. A new `ident` method is added
to `VariantDef` and `FieldDef`, which constructs the full `Ident`
using `tcx.def_ident_span()`. This method is used in the cases
where we actually need an `Ident`.

This makes incremental compilation properly track changes
to the `Span`, without all of the invalidations caused by storing
a `Span` directly via an `Ident`.

1 files changed, 2 insertions, 2 deletions

diff --git a/compiler/rustc_codegen_ssa/src/debuginfo/type_names.rs b/compiler/rustc_codegen_ssa/src/debuginfo/type_names.rs
index 93bb1aee25f..9ecab82dd2e 100644
--- a/compiler/rustc_codegen_ssa/src/debuginfo/type_names.rs
+++ b/compiler/rustc_codegen_ssa/src/debuginfo/type_names.rs
@@ -409,14 +409,14 @@ fn push_debuginfo_type_name<'tcx>(
             let max = dataful_discriminant_range.end;
             let max = tag.value.size(&tcx).truncate(max);
 
-            let dataful_variant_name = def.variants[*dataful_variant].ident.as_str();
+            let dataful_variant_name = def.variants[*dataful_variant].name.as_str();
 
             output.push_str(&format!(", {}, {}, {}", min, max, dataful_variant_name));
         } else if let Variants::Single { index: variant_idx } = &layout.variants {
             // Uninhabited enums can't be constructed and should never need to be visualized so
             // skip this step for them.
             if def.variants.len() != 0 {
-                let variant = def.variants[*variant_idx].ident.as_str();
+                let variant = def.variants[*variant_idx].name.as_str();
 
                 output.push_str(&format!(", {}", variant));
             }