diff --git a/ports/unix/main.c b/ports/unix/main.c
index 51d99ce5f1..2fcdc0fdf8 100644
--- a/ports/unix/main.c
+++ b/ports/unix/main.c
@@ -209,6 +209,11 @@ static int do_repl(void) {
         mp_hal_stdio_mode_raw();
 
     input_restart:
+        // If the GC is locked at this point there is no way out except a reset,
+        // so force the GC to be unlocked to help the user debug what went wrong.
+        if (MP_STATE_THREAD(gc_lock_depth) != 0) {
+            MP_STATE_THREAD(gc_lock_depth) = 0;
+        }
         vstr_reset(&line);
         int ret = readline(&line, mp_repl_get_ps1());
         mp_parse_input_kind_t parse_input_kind = MP_PARSE_SINGLE_INPUT;