do another saturating_add for consistency

This one is less security/correctness-critical than the other one I just
added, but I might as well be consistent.

1 files changed, 1 insertions, 1 deletions

diff --git a/b3sum/src/main.rs b/b3sum/src/main.rs
index e3dbabf..0af88bb 100644
--- a/b3sum/src/main.rs
+++ b/b3sum/src/main.rs
@@ -578,7 +578,7 @@ fn main() -> Result<()> {
                 // errors we'll still return non-zero at the end.
                 let result = hash_one_input(path, &args);
                 if let Err(e) = result {
-                    files_failed += 1;
+                    files_failed = files_failed.saturating_add(1);
                     eprintln!("{}: {}: {}", NAME, path.to_string_lossy(), e);
                 }
             }