diff --git a/passes/sat/freduce.cc b/passes/sat/freduce.cc
index 762edfdfb..f87b85da9 100644
--- a/passes/sat/freduce.cc
+++ b/passes/sat/freduce.cc
@@ -27,6 +27,7 @@
 #include <stdio.h>
 #include <string.h>
 #include <algorithm>
+#include <limits>
 
 USING_YOSYS_NAMESPACE
 PRIVATE_NAMESPACE_BEGIN