From bb8d2c3fe014c9459780db3e93ca4e182c87f4de Mon Sep 17 00:00:00 2001
From: Jonathan G Rennison <j.g.rennison@gmail.com>
Date: Sat, 4 Jul 2020 23:46:36 +0100
Subject: [PATCH] Fix 6821c0e9: Incorrect use of __builtin_mul_overflow

Fixes: #164
---
 src/core/overflowsafe_type.hpp | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/core/overflowsafe_type.hpp b/src/core/overflowsafe_type.hpp
index 45b8f48899..25fa715572 100644
--- a/src/core/overflowsafe_type.hpp
+++ b/src/core/overflowsafe_type.hpp
@@ -95,7 +95,10 @@ public:
 	inline OverflowSafeInt& operator *= (const int factor)
 	{
 #ifdef WITH_OVERFLOW_BUILTINS
-		if (unlikely(__builtin_mul_overflow(this->m_value, factor, &this->m_value))) {
+		T out;
+		if (likely(!__builtin_mul_overflow(this->m_value, factor, &out))) {
+			this->m_value = out;
+		} else {
 			this->m_value = ((this->m_value < 0) == (factor < 0)) ? T_MAX : T_MIN;
 		}
 #else