diff --git a/lib/libc/stdlib/abort.c b/lib/libc/stdlib/abort.c
index f41500739fec..4fd34dcb75c0 100644
--- a/lib/libc/stdlib/abort.c
+++ b/lib/libc/stdlib/abort.c
@@ -44,11 +44,19 @@ static char sccsid[] = "@(#)abort.c	8.1 (Berkeley) 6/4/93";
 #include "pthread_private.h"
 #endif
 
+void (*__cleanup)();
+
 void
 abort()
 {
 	sigset_t mask;
 
+	/*
+	 * POSIX requires we flush stdio buffers on abort
+	 */
+	if (__cleanup)
+		(*__cleanup)();
+
 	sigfillset(&mask);
 	/*
 	 * don't block SIGABRT to give any handler a chance; we ignore