From 3f75e8d231f3bafbe737c46f8d3777be97416f76 Mon Sep 17 00:00:00 2001
From: Justin Ethier <justin.ethier@gmail.com>
Date: Thu, 16 Mar 2017 14:07:36 +0000
Subject: [PATCH] Mark objects when collector cooperates

When the collector cooperates for a mutator it needs to mark any heap-collected objects that are stored within the mutator's data object. This prevents problems where these objects (which are essentially per-thread global roots) are incorrectly collected.
---
 gc.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/gc.c b/gc.c
index e45ec057..a77b2482 100644
--- a/gc.c
+++ b/gc.c
@@ -1696,6 +1696,15 @@ void gc_wait_handshake()
             //for (i = 0; i < m->gc_num_args; i++) {
             //  gc_mark_gray(m, m->gc_args[i]);
             //}
+            if (m->scm_thread_obj) {
+              gc_mark_gray(m, m->scm_thread_obj);
+            }
+            if (m->exception_handler_stack) {
+              gc_mark_gray(m, m->exception_handler_stack);
+            }
+            if (m->param_objs) {
+              gc_mark_gray(m, m->param_objs);
+            }
             // Also, mark everything the collector moved to the heap
             for (i = 0; i < buf_len; i++) {
               gc_mark_gray(m, m->moveBuf[i]);