Initialize QLoggingRegistry rules on first use, not qApp construction

Allows categorized logging before QCoreApplication has been created,
which otherwise would silently fail to output anything because the
category would never be enabled, despite QT_LOGGING_RULES being set.

Change-Id: Ia733105c5b6f28e22af511ced5271e45782da12b
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

3 files changed, 2 insertions, 4 deletions

diff --git a/src/corelib/io/qloggingregistry.cpp b/src/corelib/io/qloggingregistry.cpp
index 47fb1fb6b8..9a5c923323 100644
--- a/src/corelib/io/qloggingregistry.cpp
+++ b/src/corelib/io/qloggingregistry.cpp
@@ -255,6 +255,7 @@ void QLoggingSettingsParser::parseNextLine(QStringRef line)
 QLoggingRegistry::QLoggingRegistry()
     : categoryFilter(defaultCategoryFilter)
 {
+    init();
 }
 
 static bool qtLoggingDebug()
diff --git a/src/corelib/io/qloggingregistry_p.h b/src/corelib/io/qloggingregistry_p.h
index 69fc6ea4ec..768f3b4a91 100644
--- a/src/corelib/io/qloggingregistry_p.h
+++ b/src/corelib/io/qloggingregistry_p.h
@@ -113,8 +113,6 @@ class Q_AUTOTEST_EXPORT QLoggingRegistry
 public:
     QLoggingRegistry();
 
-    void init();
-
     void registerCategory(QLoggingCategory *category, QtMsgType enableForLevel);
     void unregisterCategory(QLoggingCategory *category);
 
@@ -126,6 +124,7 @@ public:
     static QLoggingRegistry *instance();
 
 private:
+    void init();
     void updateRules();
 
     static void defaultCategoryFilter(QLoggingCategory *category);
diff --git a/src/corelib/kernel/qcoreapplication.cpp b/src/corelib/kernel/qcoreapplication.cpp
index e4b1562b8b..0216baa6c3 100644
--- a/src/corelib/kernel/qcoreapplication.cpp
+++ b/src/corelib/kernel/qcoreapplication.cpp
@@ -771,8 +771,6 @@ void QCoreApplicationPrivate::init()
     if (!coreappdata()->applicationVersionSet)
         coreappdata()->applicationVersion = appVersion();
 
-    QLoggingRegistry::instance()->init();
-
 #if QT_CONFIG(library)
     // Reset the lib paths, so that they will be recomputed, taking the availability of argv[0]
     // into account. If necessary, recompute right away and replay the manual changes on top of the