From 6e2e9f676c03128e3c988c393904e3e6181b938b Mon Sep 17 00:00:00 2001
From: Michael Goulet <michael@errs.io>
Date: Tue, 10 Dec 2024 01:08:03 +0000
Subject: [PATCH] Don't ICE when encountering never in pattern

---
 compiler/rustc_hir_typeck/src/expr.rs         |  6 +++++-
 tests/ui/never_type/never-in-range-pat.rs     | 16 ++++++++++++++++
 tests/ui/never_type/never-in-range-pat.stderr | 11 +++++++++++
 3 files changed, 32 insertions(+), 1 deletion(-)
 create mode 100644 tests/ui/never_type/never-in-range-pat.rs
 create mode 100644 tests/ui/never_type/never-in-range-pat.stderr

diff --git a/compiler/rustc_hir_typeck/src/expr.rs b/compiler/rustc_hir_typeck/src/expr.rs
index 04c06169d33..1676337ab48 100644
--- a/compiler/rustc_hir_typeck/src/expr.rs
+++ b/compiler/rustc_hir_typeck/src/expr.rs
@@ -402,6 +402,11 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             })
             | hir::Node::ImplItem(hir::ImplItem { kind: hir::ImplItemKind::Const(..), .. }) => true,
 
+            hir::Node::Pat(_) => {
+                self.dcx().span_delayed_bug(expr.span, "place expr not allowed in pattern");
+                true
+            }
+
             // These nodes do not have direct sub-exprs.
             hir::Node::Param(_)
             | hir::Node::Item(_)
@@ -414,7 +419,6 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             | hir::Node::Ty(_)
             | hir::Node::AssocItemConstraint(_)
             | hir::Node::TraitRef(_)
-            | hir::Node::Pat(_)
             | hir::Node::PatField(_)
             | hir::Node::LetStmt(_)
             | hir::Node::Synthetic
diff --git a/tests/ui/never_type/never-in-range-pat.rs b/tests/ui/never_type/never-in-range-pat.rs
new file mode 100644
index 00000000000..ae2d76c172e
--- /dev/null
+++ b/tests/ui/never_type/never-in-range-pat.rs
@@ -0,0 +1,16 @@
+// Regression test for <https://github.com/rust-lang/rust/issues/133947>.
+
+// Make sure we don't ICE when there's `!` in a range pattern.
+//
+// This shouldn't be allowed anyways, but we only deny it during MIR
+// building, so make sure we handle it semi-gracefully during typeck.
+
+#![feature(never_type)]
+
+fn main() {
+    let x: !;
+    match 1 {
+        0..x => {}
+        //~^ ERROR only `char` and numeric types are allowed in range patterns
+    }
+}
diff --git a/tests/ui/never_type/never-in-range-pat.stderr b/tests/ui/never_type/never-in-range-pat.stderr
new file mode 100644
index 00000000000..c78be5350e0
--- /dev/null
+++ b/tests/ui/never_type/never-in-range-pat.stderr
@@ -0,0 +1,11 @@
+error[E0029]: only `char` and numeric types are allowed in range patterns
+  --> $DIR/never-in-range-pat.rs:13:12
+   |
+LL |         0..x => {}
+   |         -  ^ this is of type `!` but it should be `char` or numeric
+   |         |
+   |         this is of type `{integer}`
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0029`.