From 1391e1339e7205b84b6e68510cd5bc287d9c3203 Mon Sep 17 00:00:00 2001
From: Ty <amfobes@gmail.com>
Date: Wed, 30 Jul 2025 16:28:20 -0400
Subject: [PATCH] ImGui: Use localtime_r/s instead of fmt::localtime

fmt::localtime is deprecated
---
 pcsx2/ImGui/FullscreenUI.cpp  | 13 ++++++++++++-
 pcsx2/ImGui/ImGuiOverlays.cpp | 18 ++++++++++++++++--
 2 files changed, 28 insertions(+), 3 deletions(-)

diff --git a/pcsx2/ImGui/FullscreenUI.cpp b/pcsx2/ImGui/FullscreenUI.cpp
index e831ee56d4..643c4a0c53 100644
--- a/pcsx2/ImGui/FullscreenUI.cpp
+++ b/pcsx2/ImGui/FullscreenUI.cpp
@@ -50,6 +50,7 @@
 #include <algorithm>
 #include <array>
 #include <bitset>
+#include <chrono>
 #include <thread>
 #include <utility>
 #include <vector>
@@ -1440,7 +1441,17 @@ void FullscreenUI::DrawLandingTemplate(ImVec2* menu_pos, ImVec2* menu_size)
 		// draw time
 		ImVec2 time_pos;
 		{
-			heading_str.format(FSUI_FSTR("{:%H:%M}"), fmt::localtime(std::time(nullptr)));
+			// Waiting on (apple)clang support for P0355R7
+			// Migrate to std::chrono::current_zone and zoned_time then
+			const auto utc_now = std::chrono::system_clock::now();
+			const auto utc_time_t = std::chrono::system_clock::to_time_t(utc_now);
+			std::tm tm_local = {};
+#ifdef _MSC_VER
+			localtime_s(&tm_local, &utc_time_t);
+#else
+			localtime_r(&utc_time_t, &tm_local);
+#endif
+			heading_str.format(FSUI_FSTR("{:%H:%M}"), tm_local);
 
 			const ImVec2 time_size = heading_font.first->CalcTextSizeA(heading_font.second, FLT_MAX, 0.0f, "00:00");
 			time_pos = ImVec2(heading_size.x - LayoutScale(LAYOUT_MENU_BUTTON_X_PADDING) - time_size.x,
diff --git a/pcsx2/ImGui/ImGuiOverlays.cpp b/pcsx2/ImGui/ImGuiOverlays.cpp
index 1dad022dbf..4f4e95ad99 100644
--- a/pcsx2/ImGui/ImGuiOverlays.cpp
+++ b/pcsx2/ImGui/ImGuiOverlays.cpp
@@ -1069,7 +1069,14 @@ void SaveStateSelectorUI::InitializeListEntry(const std::string& serial, u32 crc
 	}
 
 	li->title = fmt::format(TRANSLATE_FS("ImGuiOverlays", "Save Slot {0}"), slot);
-	li->summary = fmt::format(TRANSLATE_FS("ImGuiOverlays", DATE_TIME_FORMAT), fmt::localtime(sd.ModificationTime));
+
+	std::tm tm_local = {};
+#ifdef _MSC_VER
+	localtime_s(&tm_local, &sd.ModificationTime);
+#else
+	localtime_r(&sd.ModificationTime, &tm_local);
+#endif
+	li->summary = fmt::format(TRANSLATE_FS("ImGuiOverlays", DATE_TIME_FORMAT), tm_local);
 	li->filename = Path::GetFileName(path);
 
 	u32 screenshot_width, screenshot_height;
@@ -1268,8 +1275,15 @@ void SaveStateSelectorUI::ShowSlotOSDMessage()
 	const std::string filename = VMManager::GetSaveStateFileName(serial.c_str(), crc, slot);
 	FILESYSTEM_STAT_DATA sd;
 	std::string date;
+	
+	std::tm tm_local = {};
+#ifdef _MSC_VER
+	localtime_s(&tm_local, &sd.ModificationTime);
+#else
+	localtime_r(&sd.ModificationTime, &tm_local);
+#endif
 	if (!filename.empty() && FileSystem::StatFile(filename.c_str(), &sd))
-		date = fmt::format(TRANSLATE_FS("ImGuiOverlays", DATE_TIME_FORMAT), fmt::localtime(sd.ModificationTime));
+		date = fmt::format(TRANSLATE_FS("ImGuiOverlays", DATE_TIME_FORMAT), tm_local);
 	else
 		date = TRANSLATE_STR("ImGuiOverlays", "no save yet");