wc: fix wrong byte counts when using --files-from0

* src/wc.c (main): Reset fstatus[0].failed between files when reusing
the fstatus[0] entry in --files-from0 mode.  This ensures a stat() is
done for each file, avoiding incorrect counts and redundant reading.
* NEWS: Mention the bug fix.
* tests/misc/wc-files0.sh: Add a test case.
Fixes http://bugs.gnu.org/23073

1 files changed, 3 insertions, 0 deletions

diff --git a/src/wc.c b/src/wc.c
index 412bda0db..64df50cd9 100644
--- a/src/wc.c
+++ b/src/wc.c
@@ -807,6 +807,9 @@ main (int argc, char **argv)
         ok = false;
       else
         ok &= wc_file (file_name, &fstatus[nfiles ? i : 0]);
+
+      if (! nfiles)
+        fstatus[0].failed = 1;
     }
  argv_iter_done: