Merge pull request #4100 from rust-lang/rustup-2024-12-20

Automatic Rustup

3 files changed, 8 insertions, 6 deletions

diff --git a/compiler/rustc_codegen_ssa/Cargo.toml b/compiler/rustc_codegen_ssa/Cargo.toml
index 628543443b3..d4bd498e28a 100644
--- a/compiler/rustc_codegen_ssa/Cargo.toml
+++ b/compiler/rustc_codegen_ssa/Cargo.toml
@@ -8,7 +8,8 @@ edition = "2021"
 ar_archive_writer = "0.4.2"
 arrayvec = { version = "0.7", default-features = false }
 bitflags = "2.4.1"
-cc = "1.1.23"
+# Pinned so `cargo update` bumps don't cause breakage
+cc = "=1.2.0"
 either = "1.5.0"
 itertools = "0.12"
 pathdiff = "0.2.0"
diff --git a/compiler/rustc_codegen_ssa/src/debuginfo/mod.rs b/compiler/rustc_codegen_ssa/src/debuginfo/mod.rs
index 88d36b19da4..7c62c03d574 100644
--- a/compiler/rustc_codegen_ssa/src/debuginfo/mod.rs
+++ b/compiler/rustc_codegen_ssa/src/debuginfo/mod.rs
@@ -65,8 +65,8 @@ fn tag_base_type_opt<'tcx>(
     });
 
     match enum_type_and_layout.layout.variants() {
-        // A single-variant enum has no discriminant.
-        Variants::Single { .. } => None,
+        // A single-variant or no-variant enum has no discriminant.
+        Variants::Single { .. } | Variants::Empty => None,
 
         Variants::Multiple { tag_encoding: TagEncoding::Niche { .. }, tag, .. } => {
             // Niche tags are always normalized to unsized integers of the correct size.
diff --git a/compiler/rustc_codegen_ssa/src/mir/place.rs b/compiler/rustc_codegen_ssa/src/mir/place.rs
index a9e80e27ed4..c634f864ffb 100644
--- a/compiler/rustc_codegen_ssa/src/mir/place.rs
+++ b/compiler/rustc_codegen_ssa/src/mir/place.rs
@@ -243,6 +243,7 @@ impl<'a, 'tcx, V: CodegenObject> PlaceRef<'tcx, V> {
             return bx.cx().const_poison(cast_to);
         }
         let (tag_scalar, tag_encoding, tag_field) = match self.layout.variants {
+            Variants::Empty => unreachable!("we already handled uninhabited types"),
             Variants::Single { index } => {
                 let discr_val = self
                     .layout
@@ -365,9 +366,9 @@ impl<'a, 'tcx, V: CodegenObject> PlaceRef<'tcx, V> {
             return;
         }
         match self.layout.variants {
-            Variants::Single { index } => {
-                assert_eq!(index, variant_index);
-            }
+            Variants::Empty => unreachable!("we already handled uninhabited types"),
+            Variants::Single { index } => assert_eq!(index, variant_index),
+
             Variants::Multiple { tag_encoding: TagEncoding::Direct, tag_field, .. } => {
                 let ptr = self.project_field(bx, tag_field);
                 let to =