gentoo-overlay/dev-qt/qtcore/files/qtcore-5.15.1-timezone-2.patch

From ffc9093a199a542791920b30d1835c3248920aa0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Andreas=20K=2E=20H=C3=BCttel?= <dilfridge@gentoo.org>
Date: Sat, 10 Oct 2020 19:26:35 +0200
Subject: [PATCH 2/2] Revert "Purge two old time-zone lookup fallbacks"

This reverts commit b0383cbd388336f698ceeac11a4f50cdff931dd9.
---
 src/corelib/time/qtimezoneprivate_tz.cpp | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/src/corelib/time/qtimezoneprivate_tz.cpp b/src/corelib/time/qtimezoneprivate_tz.cpp
index 01f9a6cce0..eea6f5e962 100644
--- a/src/corelib/time/qtimezoneprivate_tz.cpp
+++ b/src/corelib/time/qtimezoneprivate_tz.cpp
@@ -1153,6 +1153,29 @@ QByteArray QTzTimeZonePrivate::systemTimeZoneId() const
         }
     }
 
+    // On Debian Etch up to Jessie, /etc/localtime is a copy of the relevant
+    // zoneinfo file, whose name is recorded in /etc/timezone:
+    if (ianaId.isEmpty()) {
+        QFile tzif(QStringLiteral("/etc/timezone"));
+        if (tzif.open(QIODevice::ReadOnly))
+            ianaId = tzif.readAll().trimmed();
+    }
+
+    // On some Red Hat distros /etc/localtime is real file with name held in /etc/sysconfig/clock
+    // in a line like ZONE="Europe/Oslo" or TIMEZONE="Europe/Oslo"
+    if (ianaId.isEmpty()) {
+        QFile tzif(QStringLiteral("/etc/sysconfig/clock"));
+        if (tzif.open(QIODevice::ReadOnly)) {
+            while (ianaId.isEmpty() && !tzif.atEnd()) {
+                const QByteArray line(tzif.readLine().trimmed());
+                if (line.startsWith("ZONE="))
+                    ianaId = line.mid(6, line.length() - 7);
+                else if (line.startsWith("TIMEZONE="))
+                    ianaId = line.mid(10, line.length() - 11);
+            }
+        }
+    }
+
     // Some systems (e.g. uClibc) have a default value for $TZ in /etc/TZ:
     if (ianaId.isEmpty()) {
         QFile zone(QStringLiteral("/etc/TZ"));
-- 
2.28.0