Fix not respected qt.conf settings

Change 6fb569af95 introduces reloadOnQAppAvailable for
QLibrarySettings, however it is missing a reload check
for hasPaths, this breaks essentially reading custom qt.conf

Add missing check.

Fixes: QTBUG-97382
Fixes: QTBUG-97383
Fixes: QTBUG-97947
Pick-to: 6.2
Change-Id: I28379d9dd38357c290edd44b93d3bea489b9cefe
Reviewed-by: Alexey Edelev <alexey.edelev@qt.io>
Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>

src/corelib/global/qlibraryinfo.cpp

@@ -78,16 +78,16 @@ struct QLibrarySettings
 {
     QLibrarySettings();
     void load();
+    bool havePaths();
     QSettings *configuration();
 
     QScopedPointer<QSettings> settings;
-    bool havePaths;
+    bool paths;
     bool reloadOnQAppAvailable;
 };
 Q_GLOBAL_STATIC(QLibrarySettings, qt_library_settings)
 
-QLibrarySettings::QLibrarySettings() : havePaths(false)
-  , reloadOnQAppAvailable(false)
+QLibrarySettings::QLibrarySettings() : paths(false), reloadOnQAppAvailable(false)
 {
     load();
 }
@@ -99,6 +99,13 @@ QSettings *QLibrarySettings::configuration()
     return settings.data();
 }
 
+bool QLibrarySettings::havePaths()
+{
+    if (reloadOnQAppAvailable && QCoreApplication::instance() != nullptr)
+        load();
+    return paths;
+}
+
 void QLibrarySettings::load()
 {
     // If we get any settings here, those won't change when the application shows up.
@@ -109,8 +116,8 @@ void QLibrarySettings::load()
         // This code needs to be in the regular library, as otherwise a qt.conf that
         // works for qmake would break things for dynamically built Qt tools.
         QStringList children = settings->childGroups();
-        havePaths = !children.contains(QLatin1String("Platforms"))
-                    || children.contains(QLatin1String("Paths"));
+        paths = !children.contains(QLatin1String("Platforms"))
+                || children.contains(QLatin1String("Paths"));
     }
 }
 
@@ -165,7 +172,7 @@ void QLibraryInfoPrivate::reload()
 
 static bool havePaths() {
     QLibrarySettings *ls = qt_library_settings();
-    return ls && ls->havePaths;
+    return ls && ls->havePaths();
 }
 
 #endif // settings