diff --git a/test/test_ipc.cpp b/test/test_ipc.cpp
index bcc96ee..b8ac2fb 100644
--- a/test/test_ipc.cpp
+++ b/test/test_ipc.cpp
@@ -12,6 +12,7 @@
 #include <array>
 #include <limits>
 #include <utility>
+#include <unordered_map>
 
 #if defined(__GNUC__)
 #   include <cxxabi.h>  // abi::__cxa_demangle