patch for backend/ricoh2_buffer.c under FreeBSD
Note: I have only submitted the patch that already is in FreeBSD port of sane-backends; this is not my work. From https://svnweb.freebsd.org/ports/head/graphics/sane-backends/files/patch-backend_ricoh2__buffer.c?view=markup&pathrev=526253
--- backend/ricoh2_buffer.c.orig 2020-02-02 11:58:09 UTC
+++ backend/ricoh2_buffer.c
@@ -50,7 +50,7 @@
#if defined(__APPLE__) && defined(__MACH__)
#include <malloc/malloc.h>
#else
-#include <malloc.h>
+#include <stdlib.h>
#endif
#include "../include/sane/sanei_debug.h"
hope it helps.