From 7870a6e6993a2ffa755bef4751934e9c401b2f09 Mon Sep 17 00:00:00 2001
From: Dongjia Zhang <tokazerkje@outlook.com>
Date: Mon, 4 Jul 2022 20:11:28 +0200
Subject: [PATCH] Fix #675 (#691)

* fix

* wrapping
---
 libafl/src/mutators/mutations.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libafl/src/mutators/mutations.rs b/libafl/src/mutators/mutations.rs
index cf3a9c04c3..a7242ed6fb 100644
--- a/libafl/src/mutators/mutations.rs
+++ b/libafl/src/mutators/mutations.rs
@@ -271,7 +271,7 @@ where
             Ok(MutationResult::Skipped)
         } else {
             let byte = state.rand_mut().choose(input.bytes_mut());
-            *byte = (-(*byte as i16)) as u8;
+            *byte = (!(*byte)).wrapping_add(1);
             Ok(MutationResult::Mutated)
         }
     }