diff --git a/tests/unit/libutil-support/tests/hash.cc b/tests/unit/libutil-support/tests/hash.cc
index 1ff31ae6a..a06957e4b 100644
--- a/tests/unit/libutil-support/tests/hash.cc
+++ b/tests/unit/libutil-support/tests/hash.cc
@@ -1,5 +1,6 @@
-#include <regex>
-
+// required due to rapidcheck generating an incomplete-return-type error due to
+// missing include on libc++ on macOS
+#include <exception> // IWYU pragma: keep
 #include <rapidcheck.h>
 
 #include "hash.hh"