Auto merge of #7891 - giraffate:fix_ice_for_undocumented_unsafe_blocks, r=flip1995

Fix ice in `undocumented_unsafe_blocks`

Fix https://github.com/rust-lang/rust-clippy/issues/7868

changelog: Fix ice in [`undocumented_unsafe_blocks`]

tests/ui/crashes/auxiliary/ice-7868-aux.rs

@@ -0,0 +1,3 @@
+fn zero() {
+    unsafe { 0 };
+}

tests/ui/crashes/ice-7868.rs

@@ -0,0 +1,7 @@
+#![warn(clippy::undocumented_unsafe_blocks)]
+#![allow(clippy::no_effect)]
+
+#[path = "auxiliary/ice-7868-aux.rs"]
+mod zero;
+
+fn main() {}

tests/ui/crashes/ice-7868.stderr

@@ -0,0 +1,15 @@
+error: unsafe block missing a safety comment
+  --> $DIR/auxiliary/ice-7868-aux.rs:2:5
+   |
+LL |     unsafe { 0 };
+   |     ^^^^^^^^^^^^
+   |
+   = note: `-D clippy::undocumented-unsafe-blocks` implied by `-D warnings`
+help: consider adding a safety comment
+   |
+LL ~     // Safety: ...
+LL ~     unsafe { 0 };
+   |
+
+error: aborting due to previous error
+