add a regression test

Author: WaffleLapkin

tests/crashes/128097.rs

@@ -0,0 +1,14 @@
+// regression test for <https://github.com/rust-lang/rust/issues/112788>.
+// this test used to ICE because we tried to run drop glue of `x`
+// if dropping `_y` (happening at the `become` site) panicked and caused an unwind.
+//
+//@ check-pass
+#![expect(incomplete_features)]
+#![feature(explicit_tail_calls)]
+
+fn f(x: &mut ()) {
+    let _y = String::new();
+    become f(x);
+}
+
+fn main() {}