rewrite forced-unwind-terminate-pof to rmake

Author: Oneirical

Diff for: src/tools/tidy/src/allowed_run_make_makefiles.txt

@@ -51,7 +51,6 @@ run-make/extern-multiple-copies/Makefile
 run-make/extern-multiple-copies2/Makefile
 run-make/extra-filename-with-temp-outputs/Makefile
 run-make/fmt-write-bloat/Makefile
-run-make/forced-unwind-terminate-pof/Makefile
 run-make/foreign-double-unwind/Makefile
 run-make/foreign-exceptions/Makefile
 run-make/foreign-rust-exceptions/Makefile

Diff for: tests/run-make/forced-unwind-terminate-pof/Makefile

@@ -0,0 +1,16 @@
+// During a forced unwind, crossing the non-Plain Old Frame
+// would define the forced unwind as undefined behaviour, and
+// immediately abort the unwinding process. This test checks
+// that the forced unwinding takes precedence.
+// See https://github.com/rust-lang/rust/issues/101469
+
+//@ ignore-cross-compile
+//@ ignore-windows
+//Reason: pthread (POSIX threads) is not available on Windows
+
+use run_make_support::{run, rustc};
+
+fn main() {
+    rustc().input("foo.rs").run();
+    run("foo").assert_stdout_not_contains("cannot unwind");
+}