The existing test is wrong for LP64, where size_t has twice as many
relevant bits as int, not just one. (Found by inspection by
rprichard.)
diff --git a/lib/libc/stdio/setvbuf.c b/lib/libc/stdio/setvbuf.c
index 9a08d133f5f..9909dbb8ecd 100644
--- a/lib/libc/stdio/setvbuf.c
+++ b/lib/libc/stdio/setvbuf.c
@@ -31,6 +31,7 @@
* SUCH DAMAGE.
*/
+#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include "local.h"
@@ -52,7 +53,7 @@ setvbuf(FILE *fp, char *buf, int mode, size_t size)
* when setting _IONBF.
*/
if (mode != _IONBF)
- if ((mode != _IOFBF && mode != _IOLBF) || (int)size < 0)
+ if ((mode != _IOFBF && mode != _IOLBF) || size > INT_MAX)
return (EOF);
/*
