diff --git a/common/common.h b/common/common.h
index b9c3e1e5ea..3e5ee1190f 100644
--- a/common/common.h
+++ b/common/common.h
@@ -60,8 +60,8 @@ enum stream_type {
     STREAM_TYPE_COUNT,
 };
 
-extern const char *mpv_version;
-extern const char *mpv_builddate;
+extern const char *const mpv_version;
+extern const char *const mpv_builddate;
 
 char *mp_format_time(double time, bool fractions);
 char *mp_format_time_fmt(const char *fmt, double time);
diff --git a/common/version.c b/common/version.c
index 196b2ff807..7e508a7e91 100644
--- a/common/version.c
+++ b/common/version.c
@@ -16,6 +16,7 @@
  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
+#include "common.h"
 #include "version.h"
 #ifdef NO_BUILD_TIMESTAMPS
 #undef BUILDDATE