From 6b7532ae4231e25ca1a8b8d5bcb3ee0b7f29539e Mon Sep 17 00:00:00 2001
From: Timo Paulssen <timonator@perpetuum-immobile.de>
Date: Sun, 18 Feb 2018 17:28:08 +0100
Subject: [PATCH] account for thread_join deleting tc from threads

---
 src/profiler/instrument.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/profiler/instrument.c b/src/profiler/instrument.c
index 4a6629aa29..f6bb4b70fd 100644
--- a/src/profiler/instrument.c
+++ b/src/profiler/instrument.c
@@ -573,7 +573,9 @@ void MVM_profile_dump_instrumented_data(MVMThreadContext *tc) {
 
         while (thread) {
             MVMThreadContext *othertc = thread->body.tc;
-            if (othertc->prof_data) {
+            /* Check for othertc to exist because joining threads nulls out
+             * the tc entry in the thread object. */
+            if (othertc && othertc->prof_data && othertc != tc) {
                 /* If we have any call frames still on the profile stack, exit them. */
                 while (othertc->prof_data->current_call)
                     MVM_profile_log_exit(othertc);