cjdns/cjdns.entropy.patch

diff -up ./crypto/random/seed/GetEntropyRandomSeed.c.entropy ./crypto/random/seed/GetEntropyRandomSeed.c
--- ./crypto/random/seed/GetEntropyRandomSeed.c.entropy	2016-10-11 17:39:44.000000000 -0400
+++ ./crypto/random/seed/GetEntropyRandomSeed.c	2017-02-18 13:59:03.131999629 -0500
@@ -21,7 +21,11 @@
 #include <errno.h>
 #include <sys/syscall.h>
 
-#ifndef __OPENBSD__
+#define GetEntropyRandomSeed_GLIBC_HAS_IT \
+ (defined(__GNU_LIBRARY__) && defined(__GLIBC_PREREQ) && __GLIBC_PREREQ(2, 25))
+/* gcc warns against using defined() inside #define, so just copy definition */
+#if !defined(__OPENBSD__) && \
+!(defined(__GNU_LIBRARY__) && defined(__GLIBC_PREREQ) && __GLIBC_PREREQ(2, 25))
 static int getentropy(void *buf, size_t buflen)
 {
     int ret;