diff --git a/libs/ardour/globals.cc b/libs/ardour/globals.cc
index dc22d6ede2..fc0b074834 100644
--- a/libs/ardour/globals.cc
+++ b/libs/ardour/globals.cc
@@ -25,6 +25,7 @@
 #include <unistd.h>
 #include <fcntl.h>
 #include <locale.h>
+#include <errno.h>
 
 #ifdef VST_SUPPORT
 #include <fst.h>