From 7baeb26e32d5c6aeaca0a47e72bbb605b2961882 Mon Sep 17 00:00:00 2001
From: Jesse Talavera <jesse@jesse.tg>
Date: Mon, 19 May 2025 19:00:48 -0400
Subject: [PATCH] Fix undefined behavior when indexing into `ARCode::Code`
 (#2331)

- Indexing past the end of a `std::vector`'s length is undefined, even if there's extra capacity
- GCC 15 introduced an assert in `vector::operator[]`, so this line caused an abort if melonDS was built with GCC 15
- It was always undefined, but now the STL checks for it
---
 src/AREngine.cpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/AREngine.cpp b/src/AREngine.cpp
index bdda5863..0c37b321 100644
--- a/src/AREngine.cpp
+++ b/src/AREngine.cpp
@@ -58,7 +58,8 @@ void AREngine::RunCheat(const ARCode& arcode)
 
     for (;;)
     {
-        if (code >= &arcode.Code[arcode.Code.size()])
+        if (code > &arcode.Code[arcode.Code.size() - 1])
+            // If the instruction pointer is past the end of the cheat code...
             break;
 
         u32 a = *code++;