Add a check for NULL nlr_top in nlr_jump.

If no nlr_buf has been pushed, and an nlr_jump is called, then control
is transferred to nlr_jump_fail (which should bail out with a fatal
error).

1 files changed, 5 insertions, 0 deletions

diff --git a/stm/main.c b/stm/main.c
index a11a813d2..636f90021 100644
--- a/stm/main.c
+++ b/stm/main.c
@@ -79,6 +79,11 @@ void __fatal_error(const char *msg) {
     }
 }
 
+void nlr_jump_fail(void *val) {
+    printf("FATAL: uncaught exception %p\n", val);
+    __fatal_error("");
+}
+
 STATIC mp_obj_t pyb_config_source_dir = MP_OBJ_NULL;
 STATIC mp_obj_t pyb_config_main = MP_OBJ_NULL;