From 41020d1337cc9751c48cf1f33bc7a27c83ea8093 Mon Sep 17 00:00:00 2001
From: Ralf Jung <post@ralfj.de>
Date: Sun, 24 Dec 2023 11:09:58 +0100
Subject: [PATCH] fix ICE when using raw ptr in a pattern

---
 .../src/const_eval/valtrees.rs                |  2 +-
 .../null-raw-ptr-issue-119270.rs              | 19 +++++++++++++++++++
 .../null-raw-ptr-issue-119270.stderr          | 14 ++++++++++++++
 3 files changed, 34 insertions(+), 1 deletion(-)
 create mode 100644 tests/ui/consts/const_in_pattern/null-raw-ptr-issue-119270.rs
 create mode 100644 tests/ui/consts/const_in_pattern/null-raw-ptr-issue-119270.stderr

diff --git a/compiler/rustc_const_eval/src/const_eval/valtrees.rs b/compiler/rustc_const_eval/src/const_eval/valtrees.rs
index 854fe9a0765..707bb8d8933 100644
--- a/compiler/rustc_const_eval/src/const_eval/valtrees.rs
+++ b/compiler/rustc_const_eval/src/const_eval/valtrees.rs
@@ -341,7 +341,7 @@ fn valtree_into_mplace<'tcx>(
         ty::FnDef(_, _) => {
             // Zero-sized type, nothing to do.
         }
-        ty::Bool | ty::Int(_) | ty::Uint(_) | ty::Float(_) | ty::Char => {
+        ty::Bool | ty::Int(_) | ty::Uint(_) | ty::Float(_) | ty::Char | ty::RawPtr(..) => {
             let scalar_int = valtree.unwrap_leaf();
             debug!("writing trivial valtree {:?} to place {:?}", scalar_int, place);
             ecx.write_immediate(Immediate::Scalar(scalar_int.into()), place).unwrap();
diff --git a/tests/ui/consts/const_in_pattern/null-raw-ptr-issue-119270.rs b/tests/ui/consts/const_in_pattern/null-raw-ptr-issue-119270.rs
new file mode 100644
index 00000000000..03e91f2b3b1
--- /dev/null
+++ b/tests/ui/consts/const_in_pattern/null-raw-ptr-issue-119270.rs
@@ -0,0 +1,19 @@
+// run-pass
+// Eventually this will be rejected (when the future-compat lints are turned into hard errors), and
+// then this test can be removed. But meanwhile we should ensure that this works and does not ICE.
+struct NoDerive(i32);
+
+#[derive(PartialEq)]
+struct WrapEmbedded(*const NoDerive);
+
+const WRAP_UNSAFE_EMBEDDED: &&WrapEmbedded = &&WrapEmbedded(std::ptr::null());
+
+fn main() {
+    let b = match WRAP_UNSAFE_EMBEDDED {
+        WRAP_UNSAFE_EMBEDDED => true,
+        //~^ WARN: must be annotated with `#[derive(PartialEq, Eq)]`
+        //~| previously accepted
+        _ => false,
+    };
+    assert!(b);
+}
diff --git a/tests/ui/consts/const_in_pattern/null-raw-ptr-issue-119270.stderr b/tests/ui/consts/const_in_pattern/null-raw-ptr-issue-119270.stderr
new file mode 100644
index 00000000000..c186d349e72
--- /dev/null
+++ b/tests/ui/consts/const_in_pattern/null-raw-ptr-issue-119270.stderr
@@ -0,0 +1,14 @@
+warning: to use a constant of type `WrapEmbedded` in a pattern, `WrapEmbedded` must be annotated with `#[derive(PartialEq, Eq)]`
+  --> $DIR/null-raw-ptr-issue-119270.rs:13:9
+   |
+LL |         WRAP_UNSAFE_EMBEDDED => true,
+   |         ^^^^^^^^^^^^^^^^^^^^
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #62411 <https://github.com/rust-lang/rust/issues/62411>
+   = note: the traits must be derived, manual `impl`s are not sufficient
+   = note: see https://doc.rust-lang.org/stable/std/marker/trait.StructuralEq.html for details
+   = note: `#[warn(indirect_structural_match)]` on by default
+
+warning: 1 warning emitted
+