1 files changed, 2 insertions, 0 deletions
diff --git a/src/test.c b/src/test.c
index e9743cb..3f8e608 100644
--- a/src/test.c
+++ b/src/test.c
@@ -34,6 +34,8 @@ filter(coro *c, uintptr data)
     coro *seq;
     struct PrimeMsg *msg;
 
+    // Need to copy relevant variables onto the local stack
+    // Data is volatile.
     msg = (struct PrimeMsg*)data;
     seq = msg->seq; 
     p   = msg->p;