diff --git a/c/prim.c b/c/prim.c
index b599695cc4..751d341583 100644
--- a/c/prim.c
+++ b/c/prim.c
@@ -150,7 +150,8 @@ static void create_c_entry_vector() {
 
     for (i = 0; i < c_entry_vector_size; i++) {
 #ifndef PTHREADS
-      if (i == CENTRY_raw_collect_cond || i == CENTRY_raw_tc_mutex
+      if (i == CENTRY_raw_collect_cond || i == CENTRY_raw_collect_thread0_cond
+          || i == CENTRY_raw_tc_mutex
           || i == CENTRY_activate_thread || i == CENTRY_deactivate_thread
           || i == CENTRY_unactivate_thread)
         continue;