Rollup merge of #120801 - oli-obk:drop_recursion_ice, r=Nilstrieb

Avoid ICE in drop recursion check in case of invalid drop impls

fixes #120787

2 files changed, 22 insertions, 0 deletions

diff --git a/tests/ui/drop/recursion-check-on-erroneous-impl.rs b/tests/ui/drop/recursion-check-on-erroneous-impl.rs
new file mode 100644
index 00000000000..733c8b0b085
--- /dev/null
+++ b/tests/ui/drop/recursion-check-on-erroneous-impl.rs
@@ -0,0 +1,11 @@
+// can't use build-fail, because this also fails check-fail, but
+// the ICE from #120787 only reproduces on build-fail.
+// compile-flags: --emit=mir
+
+struct PrintOnDrop<'a>(&'a str);
+
+impl Drop for PrintOnDrop<'_> {
+    fn drop() {} //~ ERROR method `drop` has a `&mut self` declaration in the trait
+}
+
+fn main() {}
diff --git a/tests/ui/drop/recursion-check-on-erroneous-impl.stderr b/tests/ui/drop/recursion-check-on-erroneous-impl.stderr
new file mode 100644
index 00000000000..831adb88cef
--- /dev/null
+++ b/tests/ui/drop/recursion-check-on-erroneous-impl.stderr
@@ -0,0 +1,11 @@
+error[E0186]: method `drop` has a `&mut self` declaration in the trait, but not in the impl
+  --> $DIR/recursion-check-on-erroneous-impl.rs:8:5
+   |
+LL |     fn drop() {}
+   |     ^^^^^^^^^ expected `&mut self` in impl
+   |
+   = note: `drop` from trait: `fn(&mut Self)`
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0186`.