1 files changed, 32 insertions, 0 deletions
diff --git a/compiler/rustc_codegen_ssa/src/debuginfo/mod.rs b/compiler/rustc_codegen_ssa/src/debuginfo/mod.rs
index d1a0cf78d6a..6e3f4f0b8ef 100644
--- a/compiler/rustc_codegen_ssa/src/debuginfo/mod.rs
+++ b/compiler/rustc_codegen_ssa/src/debuginfo/mod.rs
@@ -1,2 +1,34 @@
+use rustc_middle::ty::{self, layout::TyAndLayout};
+use rustc_target::abi::Size;
+
 // FIXME(eddyb) find a place for this (or a way to replace it).
 pub mod type_names;
+
+/// Returns true if we want to generate a DW_TAG_enumeration_type description for
+/// this instead of a DW_TAG_struct_type with DW_TAG_variant_part.
+///
+/// NOTE: This is somewhat inconsistent right now: For empty enums and enums with a single
+///       fieldless variant, we generate DW_TAG_struct_type, although a
+///       DW_TAG_enumeration_type would be a better fit.
+pub fn wants_c_like_enum_debuginfo<'tcx>(enum_type_and_layout: TyAndLayout<'tcx>) -> bool {
+    match enum_type_and_layout.ty.kind() {
+        ty::Adt(adt_def, _) => {
+            if !adt_def.is_enum() {
+                return false;
+            }
+
+            match adt_def.variants().len() {
+                0 => false,
+                1 => {
+                    // Univariant enums unless they are zero-sized
+                    enum_type_and_layout.size != Size::ZERO && adt_def.all_fields().count() == 0
+                }
+                _ => {
+                    // Enums with more than one variant if they have no fields
+                    adt_def.all_fields().count() == 0
+                }
+            }
+        }
+        _ => false,
+    }
+}