diff --git a/bin/dnssec/dnssec-cds.c b/bin/dnssec/dnssec-cds.c
index 59aa45ee5f..0ef524a7e9 100644
--- a/bin/dnssec/dnssec-cds.c
+++ b/bin/dnssec/dnssec-cds.c
@@ -788,6 +788,8 @@ ds_from_cds(dns_rdatalist_t *dslist, isc_buffer_t *buf, dns_rdata_t *cds) {
 	dns_rdata_ds_t ds;
 	dns_rdata_t *rdata;
 
+	REQUIRE(buf != NULL);
+
 	rdata = rdata_get();
 
 	result = dns_rdata_tostruct(cds, &ds, NULL);
@@ -807,6 +809,8 @@ ds_from_cdnskey(dns_rdatalist_t *dslist, isc_buffer_t *buf,
 	isc_result_t result;
 	unsigned i, n;
 
+	REQUIRE(buf != NULL);
+
 	n = sizeof(dtype)/sizeof(dtype[0]);
 	for (i = 0; i < n; i++) {
 		if (dtype[i] != 0) {
diff --git a/bin/named/main.c b/bin/named/main.c
index e4e4d81261..afdb25cae8 100644
--- a/bin/named/main.c
+++ b/bin/named/main.c
@@ -1229,6 +1229,7 @@ setup(void) {
 #endif
 
 	named_server_create(named_g_mctx, &named_g_server);
+	ENSURE(named_g_server != NULL);
 	sctx = named_g_server->sctx;
 
 	/*
diff --git a/bin/named/unix/os.c b/bin/named/unix/os.c
index b1ac3b7773..c3b0bbee13 100644
--- a/bin/named/unix/os.c
+++ b/bin/named/unix/os.c
@@ -842,7 +842,7 @@ named_os_shutdownmsg(char *command, isc_buffer_t *text) {
 
 
 	/* Skip the command name. */
-	if ((ptr = strtok_r(command, " \t", &last)) == NULL) {
+	if (strtok_r(command, " \t", &last) == NULL) {
 		return;
 	}
 
diff --git a/lib/isc/tests/timer_test.c b/lib/isc/tests/timer_test.c
index 92f5b82489..128ce76b93 100644
--- a/lib/isc/tests/timer_test.c
+++ b/lib/isc/tests/timer_test.c
@@ -13,6 +13,7 @@
 
 #if HAVE_CMOCKA
 
+#include <inttypes.h>
 #include <stdarg.h>
 #include <stddef.h>
 #include <setjmp.h>
diff --git a/util/copyrights b/util/copyrights
index b762dbe39a..56c8b2f527 100644
--- a/util/copyrights
+++ b/util/copyrights
@@ -2642,6 +2642,7 @@
 ./util/nanny.pl					PERL	2000,2001,2004,2007,2012,2016,2018,2019,2020
 ./util/new-func					PERL	2005,2007,2012,2016,2018,2019,2020
 ./util/nt-kit					SH	1999,2000,2001,2004,2007,2012,2016,2018,2019,2020
+./util/parse_tsan.py				PYTHON-BIN	2020
 ./util/spacewhack.pl				PERL	2000,2001,2004,2007,2012,2016,2018,2019,2020
 ./util/tabify-changes				SH	2004,2007,2012,2016,2018,2019,2020
 ./util/update-drafts.pl				PERL	2000,2001,2004,2007,2012,2016,2018,2019,2020
diff --git a/util/parse_tsan.py b/util/parse_tsan.py
new file mode 100755
index 0000000000..6e4e478995
--- /dev/null
+++ b/util/parse_tsan.py
@@ -0,0 +1,112 @@
+#!/usr/bin/env python3
+############################################################################
+# Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+#
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+#
+# See the COPYRIGHT file distributed with this work for additional
+# information regarding copyright ownership.
+############################################################################
+
+import sys, os, os.path, re
+from hashlib import sha256
+
+class State:
+    inside = False
+    block = ""
+    last_line = None
+
+    mutexes = {}
+    m_index = 1
+    threads = {}
+    t_index = 1
+    pointers = {}
+    p_index = 1
+
+    def init(self):
+        self.reset()
+
+    def reset(self):
+        self.inside = False
+        self.block = ""
+
+        self.mutexes = {}
+        self.threads = {}
+        self.pointers = {}
+        self.pointers["0x000000000000"] = 0
+
+        self.m_index = 1
+        self.t_index = 1
+        self.p_index = 1
+
+top = os.path.dirname(os.path.dirname(os.path.realpath(__file__)))
+
+out = os.path.join(top, "tsan")
+
+if not os.path.isdir(out):
+    os.mkdir(out)
+
+# Regular Expressions
+mutex = re.compile(r"M\d+")
+thread = re.compile(r"T\d+")
+stack = re.compile(r"\s\(\S+\+0x\S+\)")
+pointer = re.compile(r"0x[0-9a-f]+")
+pid = re.compile(r"\(pid=\d+,?\)")
+tid = re.compile(r"tid=\d+,?\s*")
+worker = re.compile(r"\s+'(isc-worker|isc-net-)\d+'")
+path = re.compile(top + "/")
+
+s = State()
+
+
+with open(sys.argv[1], "r", encoding='utf-8') as f:
+    lines = f.readlines()
+    for line in lines:
+        if line == "==================\n":
+           if not s.inside:
+               s.inside = True
+           else:
+               dname = os.path.join(out, sha256(s.last_line.encode('utf-8')).hexdigest())
+               if not os.path.isdir(dname):
+                   os.mkdir(dname)
+               fname = os.path.join(dname, sha256(s.block.encode('utf-8')).hexdigest() + ".tsan")
+               if not os.path.isfile(fname):
+                   with open(fname, "w", encoding='utf-8') as w:
+                       w.write(s.block)
+               s.reset()
+        else:
+            for m in mutex.finditer(line):
+                k = m.group()
+                if k not in s.mutexes:
+                    s.mutexes[k] = s.m_index
+                    s.m_index += 1
+            for m in thread.finditer(line):
+                k = m.group()
+                if k not in s.threads:
+                    s.threads[k] = s.t_index
+                    s.t_index += 1
+            for m in pointer.finditer(line):
+                k = m.group()
+                if k not in s.pointers:
+                    s.pointers[k] = s.p_index
+                    s.p_index += 1
+            for k, v in s.mutexes.items():
+                r = re.compile(k)
+                line = r.sub("M%s" % v, line)
+            for k, v in s.threads.items():
+                r = re.compile(k)
+                line = r.sub("T%s" % v, line)
+            for k, v in s.pointers.items():
+                r = re.compile(k)
+                line = r.sub("0x%s" % str(v).zfill(12), line)
+
+            line = stack.sub("", line)
+            line = pid.sub("", line)
+            line = tid.sub("", line)
+            line = worker.sub("", line)
+            line = path.sub("", line)
+
+            s.block += line
+            s.last_line = line