From bf30d626bca6e7e48e7fd67a15a389a74c86470c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Nguy=E1=BB=85n=20Gia=20Phong?= <mcsinyx@disroot.org>
Date: Mon, 10 Mar 2025 17:50:35 +0900
Subject: [PATCH] fuzzer: don't remove or modify byte of empty input

---
 lib/fuzzer.zig | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/fuzzer.zig b/lib/fuzzer.zig
index 92b621d07f72..1f565db856a9 100644
--- a/lib/fuzzer.zig
+++ b/lib/fuzzer.zig
@@ -287,7 +287,8 @@ const Fuzzer = struct {
         while (true) {
             const chosen_index = rng.uintLessThanBiased(usize, f.corpus.items.len);
             const modification = rng.enumValue(Mutation);
-            f.mutateAndRunOne(chosen_index, modification);
+            if (f.corpus.items[chosen_index].bytes.len > 0 or modification == .add_byte)
+                f.mutateAndRunOne(chosen_index, modification);
         }
     }