diff --git a/main/source/mod/AvHAIMath.cpp b/main/source/mod/AvHAIMath.cpp
index 13d823b4..ed9a58f7 100644
--- a/main/source/mod/AvHAIMath.cpp
+++ b/main/source/mod/AvHAIMath.cpp
@@ -13,6 +13,7 @@
 
 #include <string>
 #include <sstream>
+#include <cfloat>
 
 extern enginefuncs_t g_engfuncs;