From e575f05a8b6895fdafd27f5fccca54b60876f318 Mon Sep 17 00:00:00 2001
From: y21 <30553356+y21@users.noreply.github.com>
Date: Tue, 2 Apr 2024 15:04:25 +0200
Subject: [PATCH] avoid an ICE in `ptr_as_ptr` when getting the def_id of a
 local

---
 clippy_lints/src/casts/ptr_as_ptr.rs |  2 +-
 tests/ui/crashes/ice-12616.fixed     |  7 +++++++
 tests/ui/crashes/ice-12616.rs        |  7 +++++++
 tests/ui/crashes/ice-12616.stderr    | 19 +++++++++++++++++++
 4 files changed, 34 insertions(+), 1 deletion(-)
 create mode 100644 tests/ui/crashes/ice-12616.fixed
 create mode 100644 tests/ui/crashes/ice-12616.rs
 create mode 100644 tests/ui/crashes/ice-12616.stderr

diff --git a/clippy_lints/src/casts/ptr_as_ptr.rs b/clippy_lints/src/casts/ptr_as_ptr.rs
index 35e36e9ef3f5..16de93136854 100644
--- a/clippy_lints/src/casts/ptr_as_ptr.rs
+++ b/clippy_lints/src/casts/ptr_as_ptr.rs
@@ -62,8 +62,8 @@ pub(super) fn check(cx: &LateContext<'_>, expr: &Expr<'_>, msrv: &Msrv) {
         // we omit following `cast`:
         let omit_cast = if let ExprKind::Call(func, []) = cast_expr.kind
             && let ExprKind::Path(ref qpath @ QPath::Resolved(None, path)) = func.kind
+            && let Some(method_defid) = path.res.opt_def_id()
         {
-            let method_defid = path.res.def_id();
             if cx.tcx.is_diagnostic_item(sym::ptr_null, method_defid) {
                 OmitFollowedCastReason::Null(qpath)
             } else if cx.tcx.is_diagnostic_item(sym::ptr_null_mut, method_defid) {
diff --git a/tests/ui/crashes/ice-12616.fixed b/tests/ui/crashes/ice-12616.fixed
new file mode 100644
index 000000000000..a5a5b3d1e78e
--- /dev/null
+++ b/tests/ui/crashes/ice-12616.fixed
@@ -0,0 +1,7 @@
+#![warn(clippy::ptr_as_ptr)]
+#![allow(clippy::unnecessary_operation, clippy::unnecessary_cast)]
+
+fn main() {
+    let s = std::ptr::null::<()>;
+    s().cast::<()>();
+}
diff --git a/tests/ui/crashes/ice-12616.rs b/tests/ui/crashes/ice-12616.rs
new file mode 100644
index 000000000000..6ee9a5ec08fe
--- /dev/null
+++ b/tests/ui/crashes/ice-12616.rs
@@ -0,0 +1,7 @@
+#![warn(clippy::ptr_as_ptr)]
+#![allow(clippy::unnecessary_operation, clippy::unnecessary_cast)]
+
+fn main() {
+    let s = std::ptr::null::<()>;
+    s() as *const ();
+}
diff --git a/tests/ui/crashes/ice-12616.stderr b/tests/ui/crashes/ice-12616.stderr
new file mode 100644
index 000000000000..ef573f55cf36
--- /dev/null
+++ b/tests/ui/crashes/ice-12616.stderr
@@ -0,0 +1,19 @@
+error: `as` casting between raw pointers without changing its mutability
+  --> tests/ui/crashes/ice-12616.rs:6:5
+   |
+LL |     s() as *const ();
+   |     ^^^^^^^^^^^^^^^^ help: try `pointer::cast`, a safer alternative: `s().cast::<()>()`
+   |
+   = note: `-D clippy::ptr-as-ptr` implied by `-D warnings`
+   = help: to override `-D warnings` add `#[allow(clippy::ptr_as_ptr)]`
+
+error: `as` casting between raw pointers without changing its mutability
+  --> tests/ui/crashes/ice-12616.rs:6:5
+   |
+LL |     s() as *const ();
+   |     ^^^^^^^^^^^^^^^^ help: try `pointer::cast`, a safer alternative: `s().cast::<()>()`
+   |
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
+error: aborting due to 2 previous errors
+