diff --git a/libcockatrice_utility/libcockatrice/utility/system_memory_querier.cpp b/libcockatrice_utility/libcockatrice/utility/system_memory_querier.cpp
index e42aee987..9a4539256 100644
--- a/libcockatrice_utility/libcockatrice/utility/system_memory_querier.cpp
+++ b/libcockatrice_utility/libcockatrice/utility/system_memory_querier.cpp
@@ -6,6 +6,7 @@
 
 #ifdef Q_OS_LINUX
 #include <QFile>
+#include <QRegularExpression>
 #include <QTextStream>
 #endif