use wxLogBuffer to ensure that we don't lose error messages during initialization; only switch to wxLogGui when it's really safe to use it

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@34557 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/common/appbase.cpp

@@ -142,14 +142,6 @@ wxAppConsole::~wxAppConsole()
 
 bool wxAppConsole::Initialize(int& argc, wxChar **argv)
 {
-#if wxUSE_LOG
-    // If some code logged something before wxApp instance was created,
-    // wxLogStderr was set as the target. Undo it here by destroying the
-    // current target. It will be re-created next time logging is needed, but
-    // this time wxAppTraits will be used:
-    delete wxLog::SetActiveTarget(NULL);
-#endif // wxUSE_LOG
-
     // remember the command line arguments
     this->argc = argc;
     this->argv = argv;

src/common/init.cpp

@@ -209,6 +209,15 @@ static void FreeConvertedArgs()
 // initialization which is always done (not customizable) before wxApp creation
 static bool DoCommonPreInit()
 {
+#if wxUSE_LOG
+    // install temporary log sink: we can't use wxLogGui before wxApp is
+    // constructed and if we use wxLogStderr, all messages during
+    // initialization simply disappear under Windows
+    //
+    // note that we will delete this log target below
+    wxLog::SetActiveTarget(new wxLogBuffer);
+#endif // wxUSE_LOG
+
     return true;
 }
 
@@ -217,7 +226,13 @@ static bool DoCommonPostInit()
 {
     wxModule::RegisterModules();
 
-    return wxModule::InitializeModules();
+    if ( !wxModule::InitializeModules() )
+    {
+        wxLogError(_("Initialization failed in post init, aborting."));
+        return false;
+    }
+
+    return true;
 }
 
 bool wxEntryStart(int& argc, wxChar **argv)
@@ -286,6 +301,14 @@ bool wxEntryStart(int& argc, wxChar **argv)
     // and the cleanup object from doing cleanup
     callAppCleanup.Dismiss();
 
+#if wxUSE_LOG
+    // now that we have a valid wxApp (wxLogGui would have crashed if we used
+    // it before now), we can delete the temporary sink we had created for the
+    // initialization messages -- the next time logging function is called, the
+    // sink will be recreated but this time wxAppTraits will be used
+    delete wxLog::SetActiveTarget(NULL);
+#endif // wxUSE_LOG
+
     return true;
 }
 
@@ -385,6 +408,8 @@ int wxEntryReal(int& argc, wxChar **argv)
     // library initialization
     if ( !wxEntryStart(argc, argv) )
     {
+        // flush any log messages explaining why we failed
+        delete wxLog::SetActiveTarget(NULL);
         return -1;
     }