From 9c27e0251c8ff12dc258717a2e36b20c2d8e2786 Mon Sep 17 00:00:00 2001
From: Chayim Refael Friedman <chayimfr@gmail.com>
Date: Mon, 27 Jan 2025 18:57:31 +0200
Subject: [PATCH] Report calling unsafe fn pointer as unsafe

---
 crates/hir-ty/src/diagnostics/unsafe_check.rs        |  8 +++++++-
 .../ide-diagnostics/src/handlers/missing_unsafe.rs   | 12 ++++++++++++
 2 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/crates/hir-ty/src/diagnostics/unsafe_check.rs b/crates/hir-ty/src/diagnostics/unsafe_check.rs
index f655692429..2aca99c93b 100644
--- a/crates/hir-ty/src/diagnostics/unsafe_check.rs
+++ b/crates/hir-ty/src/diagnostics/unsafe_check.rs
@@ -240,9 +240,15 @@ impl<'a> UnsafeVisitor<'a> {
         let inside_assignment = mem::replace(&mut self.inside_assignment, false);
         match expr {
             &Expr::Call { callee, .. } => {
-                if let Some(func) = self.infer[callee].as_fn_def(self.db) {
+                let callee = &self.infer[callee];
+                if let Some(func) = callee.as_fn_def(self.db) {
                     self.check_call(current, func);
                 }
+                if let TyKind::Function(fn_ptr) = callee.kind(Interner) {
+                    if fn_ptr.sig.safety == chalk_ir::Safety::Unsafe {
+                        self.on_unsafe_op(current.into(), UnsafetyReason::UnsafeFnCall);
+                    }
+                }
             }
             Expr::Path(path) => {
                 let guard =
diff --git a/crates/ide-diagnostics/src/handlers/missing_unsafe.rs b/crates/ide-diagnostics/src/handlers/missing_unsafe.rs
index d48464769c..323a5723d4 100644
--- a/crates/ide-diagnostics/src/handlers/missing_unsafe.rs
+++ b/crates/ide-diagnostics/src/handlers/missing_unsafe.rs
@@ -862,6 +862,18 @@ fn bar() {
 fn baz() {
     foo();
  // ^^^^^ 💡 error: call to unsafe function is unsafe and requires an unsafe function or block
+}
+        "#,
+        );
+    }
+
+    #[test]
+    fn unsafe_fn_ptr_call() {
+        check_diagnostics(
+            r#"
+fn f(it: unsafe fn()){
+    it();
+ // ^^^^ 💡 error: call to unsafe function is unsafe and requires an unsafe function or block
 }
         "#,
         );