--- a/main.c
+++ b/main.c
@@ -33,6 +33,11 @@
#include <ncurses.h>
#endif
+// musl has no this constant
+#ifndef TCPI_OPT_SYN_DATA
+#define TCPI_OPT_SYN_DATA 32
+#endif
+
#include "gen.h"
#include "help.h"
#include "colors.h"