diff --git a/tests/test_crypto_aead_cpp.cpp b/tests/test_crypto_aead_cpp.cpp
index e6e50018..9724581d 100644
--- a/tests/test_crypto_aead_cpp.cpp
+++ b/tests/test_crypto_aead_cpp.cpp
@@ -2,6 +2,7 @@
 // The C++ AEAD codecs (src/crypto/aead.hpp) against RFC 5869 vectors and,
 // differentially, against the C implementation in aead.cpp: every stream
 // and packet produced by one side must be accepted by the other.
+#include <algorithm>
 #include <cstdint>
 #include <cstdlib>
 #include <cstring>