diff --git a/include/bsd/stdlib.h b/include/bsd/stdlib.h
index f7bcbd0..ac60dc6 100644
--- a/include/bsd/stdlib.h
+++ b/include/bsd/stdlib.h
@@ -51,11 +51,15 @@
 #include <stdint.h>
 
 __BEGIN_DECLS
+#if !defined(__GLIBC__) || \
+    !__GLIBC_PREREQ(2, 36) || \
+    !defined(_DEFAULT_SOURCE)
 uint32_t arc4random(void);
-void arc4random_stir(void);
-void arc4random_addrandom(unsigned char *dat, int datlen);
 void arc4random_buf(void *_buf, size_t n);
 uint32_t arc4random_uniform(uint32_t upper_bound);
+#endif
+void arc4random_stir(void);
+void arc4random_addrandom(unsigned char *dat, int datlen);
 
 int dehumanize_number(const char *str, int64_t *size);