Index: stdio/fgetwln.c
===================================================================
RCS file: /cvs/src/lib/libc/stdio/fgetwln.c,v
retrieving revision 1.1
diff -p -U11 -r1.1 fgetwln.c
--- stdio/fgetwln.c	12 Jan 2015 20:58:07 -0000	1.1
+++ stdio/fgetwln.c	21 Aug 2016 14:00:32 -0000
@@ -59,23 +59,23 @@ fgetwln(FILE * __restrict fp, size_t *le
 
 	len = 0;
 	while ((wc = __fgetwc_unlock(fp)) != WEOF) {
 #define	GROW	512
 		if (len >= fp->_lb._size / sizeof(wchar_t) &&
 		    __slbexpand(fp, len + GROW))
 			goto error;
 		*((wchar_t *)fp->_lb._base + len++) = wc;
 		if (wc == L'\n')
 			break;
 	}
-	if (len == 0)
+	if (len == 0 || fp->_flags & __SERR)
 		goto error;
 
 	FUNLOCKFILE(fp);
 	*lenp = len;
 	return (wchar_t *)fp->_lb._base;
 
 error:
 	FUNLOCKFILE(fp);
 	*lenp = 0;
 	return NULL;
 }