From e24374a137ebb1c03da1fe5b0650b9b4eb9312b0 Mon Sep 17 00:00:00 2001
From: Crementif <26669564+Crementif@users.noreply.github.com>
Date: Fri, 28 Aug 2026 02:09:30 +0200
Subject: [PATCH] coreinit: fix OSTicksToCalendarTime accuracy w/ leap years

---
 src/Cafe/OS/libs/coreinit/coreinit_Time.cpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/Cafe/OS/libs/coreinit/coreinit_Time.cpp b/src/Cafe/OS/libs/coreinit/coreinit_Time.cpp
index 50a404f4..e4bc6aae 100644
--- a/src/Cafe/OS/libs/coreinit/coreinit_Time.cpp
+++ b/src/Cafe/OS/libs/coreinit/coreinit_Time.cpp
@@ -139,6 +139,7 @@ namespace coreinit
 
 		// calculate month and day
 		uint32 dayInYear = (uint32)(daysSince0AD - yearStartDay);
+		uint32 dayOfYear = dayInYear; // dayInYear gets shifted below to index the non-leap month table, so keep a copy
 		bool isLeapYear = IsLeapYear(year);
 
 		uint32 month = 0; // 0-11
@@ -239,7 +240,7 @@ namespace coreinit
 			}
 		}
 
-		calenderStruct->dayOfYear = dayInYear;
+		calenderStruct->dayOfYear = dayOfYear;
 		calenderStruct->month = month;
 		calenderStruct->dayOfMonth = dayInMonth + 1;
 	}