Add test statmemprof/thread_exit_in_callback.

testsuite/tests/statmemprof/thread_exit_in_callback.ml

@@ -0,0 +1,18 @@
+(* TEST
+modules = "thread_exit_in_callback_stub.c"
+exit_status = "42"
+* hassysthreads
+include systhreads
+** bytecode
+** native
+*)
+
+(* We cannot tell Ocamltest that this program is supposed to stop with
+   a fatal error. Instead, we install a fatal error hook and call exit(42) *)
+external install_fatal_error_hook : unit -> unit = "install_fatal_error_hook"
+
+let _ =
+  install_fatal_error_hook ();
+  Gc.Memprof.(start ~callstack_size:10 ~sampling_rate:1.
+    { null_tracker with alloc_minor = fun _ -> Thread.exit (); None });
+  ignore (Sys.opaque_identity (ref 1))

testsuite/tests/statmemprof/thread_exit_in_callback.reference

@@ -0,0 +1 @@
+Fatal error hook: Thread.exit called from a memprof callback.

testsuite/tests/statmemprof/thread_exit_in_callback_stub.c

@@ -0,0 +1,16 @@
+#include <stdio.h>
+#include "caml/misc.h"
+#include "caml/mlvalues.h"
+
+void fatal_error_hook_exit_3 (char *msg, va_list args) {
+  fprintf(stderr, "Fatal error hook: ");
+  vfprintf(stderr, msg, args);
+  fprintf(stderr, "\n");
+  exit(42);
+}
+
+
+value install_fatal_error_hook (value unit) {
+  caml_fatal_error_hook = fatal_error_hook_exit_3;
+  return Val_unit;
+}