+#define BSD4_2 /* Tell code below to use getrlimit. */
+
+/* Old Linux startup code won't define __data_start. */
+extern int etext, __data_start; weak_extern (__data_start)
+#define start_of_data() (&__data_start ?: &etext)
+
+#else /* not _LIBC */
+
+#ifdef HAVE_SYS_RESOURCE_H
+# include <sys/time.h>
+# include <sys/resource.h>
+#else
+# if HAVE_SYS_VLIMIT_H
+# include <sys/vlimit.h> /* Obsolete, says glibc */
+# endif
+#endif
+
+#ifdef __bsdi__
+#define BSD4_2
+#endif
+
+#ifdef CYGWIN
+#define BSD4_2