diff --git a/dnstap/dtstream.c b/dnstap/dtstream.c
index 2d55d197f..bb862d441 100644
--- a/dnstap/dtstream.c
+++ b/dnstap/dtstream.c
@@ -1579,7 +1579,7 @@ static int dtio_open_output_local(struct dt_io_thread* dtio)
 	memset(&s, 0, sizeof(s));
 #ifdef HAVE_STRUCT_SOCKADDR_UN_SUN_LEN
         /* this member exists on BSDs, not Linux */
-        s.sun_len = (unsigned)sizeof(usock);
+        s.sun_len = (unsigned)sizeof(s);
 #endif
 	s.sun_family = AF_LOCAL;
 	/* length is 92-108, 104 on FreeBSD */
diff --git a/doc/Changelog b/doc/Changelog
index 970cbcf15..27f6a66f0 100644
--- a/doc/Changelog
+++ b/doc/Changelog
@@ -1,6 +1,9 @@
 2 March 2020: George
 	- Fix compiler warning in dns64/dns64.c
 
+2 March 2020: Wouter
+	- Fix #177: dnstap does not build on macOS.
+
 28 February 2020: Ralph
 	- Merge PR #172: Add IBM s390x arch for testing, by noloader.