diff --git a/meson.build b/meson.build
index 2be725096..8cb5f4acc 100644
--- a/meson.build
+++ b/meson.build
@@ -177,6 +177,11 @@ endif
 config_h.set('HAVE_WAYLAND', enable_wayland,
              description: 'Define to 1 if Wayland is enabled')
 
+# thunderbolt
+config_h.set10('HAVE_FN_EXPLICIT_BZERO',
+               cc.has_function('explicit_bzero', prefix: '''#include <string.h>'''),
+               description: 'Define if explicit_bzero is available')
+
 if host_is_linux
   # network manager
   network_manager_deps = [