diff --git a/include/libtorrent/aux_/session_interface.hpp b/include/libtorrent/aux_/session_interface.hpp
index b3738bd7c..342e64907 100644
--- a/include/libtorrent/aux_/session_interface.hpp
+++ b/include/libtorrent/aux_/session_interface.hpp
@@ -52,6 +52,7 @@ POSSIBILITY OF SUCH DAMAGE.
 
 #ifndef TORRENT_DISABLE_LOGGING
 #include <boost/shared_ptr.hpp>
+#include <cstdarg> // for va_list
 #endif
 
 #ifdef TORRENT_USE_OPENSSL
diff --git a/src/disk_io_thread.cpp b/src/disk_io_thread.cpp
index 976997bb4..2d4bbd704 100644
--- a/src/disk_io_thread.cpp
+++ b/src/disk_io_thread.cpp
@@ -62,6 +62,7 @@ POSSIBILITY OF SUCH DAMAGE.
 #if __cplusplus >= 201103L || defined __clang__
 
 #if DEBUG_DISK_THREAD
+#include <cstdarg> // for va_list
 #define DLOG(...) debug_log(__VA_ARGS__)
 #else
 #define DLOG(...) do {} while(false)
diff --git a/src/session_impl.cpp b/src/session_impl.cpp
index 1a183500b..b54a5eb18 100644
--- a/src/session_impl.cpp
+++ b/src/session_impl.cpp
@@ -107,6 +107,8 @@ POSSIBILITY OF SUCH DAMAGE.
 // for logging stat layout
 #include "libtorrent/stat.hpp"
 
+#include <cstdarg> // for va_list
+
 // for logging the size of DHT structures
 #ifndef TORRENT_DISABLE_DHT
 #include <libtorrent/kademlia/find_data.hpp>