diff --git a/opm/autodiff/WellStateFullyImplicitBlackoilDense.hpp b/opm/autodiff/WellStateFullyImplicitBlackoilDense.hpp
index e715874a6..ff8838029 100644
--- a/opm/autodiff/WellStateFullyImplicitBlackoilDense.hpp
+++ b/opm/autodiff/WellStateFullyImplicitBlackoilDense.hpp
@@ -35,6 +35,7 @@
 #include <map>
 #include <algorithm>
 #include <array>
+#include <cmath>
 
 namespace Opm
 {