Problem with QObject::dumpObjectTree() on ubuntu 9.10

tokyoben

Hello everybody!

I'm somewhat of a novice to Qt and I'm trying to learn it using an Ubuntu 9.10 box. I've done a fair amount of google search and tried different things before posting this thread, so as not to bother people needlessly. However, after several hours of frustration, I could not get dumpObjectTree() to produce anything for a simple console app (even QDebug is not working). I've looked thru my Qt libs and I don't see anything with a dbg ending (or anything roughly similar that). Somewhere I found a post where there was a hint that there may be some limitations using Qtdebug libraries on Linux.

Among the things I've tried:

added CONFIG += debug to .pro file
added CONFIG += release_and_debug to .pro file
installed the libqt4-dbg using Synaptic

Even when I used QtCreator on debug mode I could not get any response from dumpObjectTree().

So it seems to me that there is either something basically wrong with my procedure (unlikely I think) or I'm not using the appropriate libraries.

Could anybody give me a hint on how to go about this?

Thanks!

viswesr

I use Ubuntu 10.04 and Qt 4.7.0 snapshot version compiled from source code, dumpObjectTree works well. eg:

@int main(int argc, char *argv[])
{
QApplication a(argc, argv);
MainWindow w;
w.setWindowFlags(Qt::WindowStaysOnTopHint);
w.dumpObjectTree();
w.show();

return a.exec&#40;&#41;;

}
@

output:
@
MainWindow::MainWindow
QMainWindowLayout::_layout
QRubberBand::qt_rubberband
QMenuBar::menuBar
QToolButton::qt_menubar_ext_button
QToolBar::mainToolBar
QToolBarLayout::
QToolBarExtension::qt_toolbar_ext_button
QAction::
QWidget::centralWidget
QStatusBar::statusBar
QSizeGrip::
QHBoxLayout::
QVBoxLayout::
QHBoxLayout::
@

1.If you are using Qt creator, use debug Build
2.Try compiling Qt from source / use the Nokia released version instead of distribution version.

tokyoben

Thanks for the reply.

I've downloaded the latest Qt SDK using this link
http://qt.nokia.com/downloads/sdk-linux-x11-32bit-cpp (http://get.qt.nokia.com/qtsdk/qt-sdk-linux-x86-opensource-2010.04.bin)

I tried using the debug build and it didn't work!

I also copied all the lib*.so.4.6.1.debug files from /usr/local/Trolltech/Qt-4.6.1/lib to my /usr/lib folder and renamed them *_debug.so and altered the Makefile to use only the now created libQtCore_debug.so library. It also didn't work!

I tried to find the source code for the latest Qt SDK (or even the framework only) from the Nokia site, but I could only find pre-compiled binaries.

Since the example that I'm tried to run is so simple (no GUI only console) I'm almost certain that I have a library compatibility problem OR I'm not using some requeired compiler/linker flags (unlikely).

I'm almost giving up on getting dumpObjectTree and QDebug to run on my Ubuntu 9.10!

Thanks for the attention!

viswesr

Can you post the .pro and example .cpp files?

Also try Qt 4.7.0 RC1 available here:
"Qt prerelease downloads":http://qt.nokia.com/developer/qt-qtcreator-prerelease
"Qt 4.7.0 RC1 Src":http://get.qt.nokia.com/qt/source/qt-everywhere-opensource-src-4.7.0-rc1.tar.gz

tokyoben

The example is a simple one based on the web available notes by Ezust, really basic stuff!
1)Below are the .pro and cpp/h files I used with Eclipse:

1.a)
######################################################################

Automatically generated by qmake (2.01a) Tue Sep 14 15:39:04 2010

######################################################################

TEMPLATE = app
TARGET =
DEPENDPATH += .
INCLUDEPATH += .
LIBS = -L/usr/local/Trolltech/Qt-4.6.1/lib
#CONFIG += debug_and_release
CONFIG += debug

Input

HEADERS += Personna.h
SOURCES += main.cpp Personna.cpp

1.b)main.cpp

/*

main.cpp
Created on: Sep 14, 2010
```
 Author: ben
```

*/

#include <QTextStream>
#include <QDebug>
#include "Personna.h"

static QTextStream cout(stdout, QIODevice::WriteOnly);

void showTree(QObject* theparent){
foreach(QObject* const person, theparent->children()){
if(person->parent()==theparent){
cout << "Member: "<<person->objectName()<<" - Parent:"<<theparent->objectName()<<endl;
showTree(person);
}
}
}
int main(int , char**) {
cout << "First we create a bunch of objects." << endl;
Personna bunch(0, "A Stack Object");
/* other objects are created on the heap */
Personna *mike = new Personna(&bunch, "Mike");
Personna *carol = new Personna(&bunch, "Carol");
new Personna(mike, "Greg");
new Personna(mike, "Peter");
new Personna(mike, "Bobby");
new Personna(carol, "Marcia");
new Personna(carol, "Jan");
new Personna(carol, "Cindy");
Personna *alice=new Personna(0, "Alice");
new Personna(alice, "King");
new Personna(alice, "Queen");

cout << "\nDisplay the list using QObject::dumpObjectTree()"
          << endl;
bunch.dumpObjectTree();
QDebug(&QString(" QDebug() called!"));

showTree(&bunch);
showTree(alice);
cout << "\nProgram finished - destroy all objects." << endl;
return 0;

}

1.c) Personna.cpp
/*

Personna.cpp
Created on: Sep 14, 2010
```
 Author: ben
```

*/

#include "Personna.h"
#include <QTextStream>

static QTextStream cout(stdout, QIODevice::WriteOnly);
Personna::Personna(QObject* parent, QString name)
: QObject(parent) {
setObjectName(name);
cout << QString("Constructing Person: %1").arg(name) << endl;
}
Personna::~Personna() {
cout << QString("Destroying Person: %1").arg(objectName()) <<
endl;
}
1.d) Personna.h
/*

Personna.h
Created on: Sep 14, 2010
```
 Author: ben
```

*/

#ifndef PERSONNA_H_
#define PERSONNA_H_

#include <QObject>
#include <QString>

class Personna : public QObject{
public:
Personna(QObject* parent, QString name);
virtual ~Personna();
};

#endif /* PERSONNA_H_ */
2)Below is the .pro file I used with QtCreator(latest linux binary release) (The cpp/h files are the same as above):
#-------------------------------------------------

Project created by QtCreator 2010-09-15T00:42:26

#-------------------------------------------------

QT += core

QT -= gui

TARGET = qobj
CONFIG += console
CONFIG -= app_bundle
CONFIG += debug

TEMPLATE = app

SOURCES += main.cpp
personna.cpp

HEADERS +=
personna.h

tobias.hunger

Would you mind adding some code tags? Your comment is hardly readable right now.

tokyoben

Trying again!
The example is a simple one based on the web available notes by Ezust (I changed slightly the code), really basic stuff!
1)Below are the .pro and cpp/h files I used with Eclipse:

1.a)
@
######################################################################

Automatically generated by qmake (2.01a) Tue Sep 14 15:39:04 2010

######################################################################

TEMPLATE = app

TARGET =

DEPENDPATH += .

INCLUDEPATH += .

LIBS = -L/usr/local/Trolltech/Qt-4.6.1/lib

#CONFIG += debug_and_release

CONFIG += debug

Input

  HEADERS += Personna.h


  SOURCES += main.cpp Personna.cpp

@
1.b)main.cpp
@

  /*
  * main.cpp * * Created on: Sep 14, 2010 * Author: ben */



  #include “Personna.h”



  static QTextStream cout(stdout, QIODevice::WriteOnly);

void showTree(QObject* theparent){
foreach(QObject* const person, theparent->children()){
cout << "Member: "<< person->objectName()<<" - Parent:"<<theparent->objectName()<<endl;
showTree(person);
}
}

  int main(int , char**) {

cout << “First we create a bunch of objects.” << endl;

Personna bunch(0, “A Stack Object”);

/* other objects are created on the heap */

Personna *mike = new Personna(&bunch, “Mike”);

Personna *carol = new Personna(&bunch, “Carol”);

new Personna(mike, “Greg”);

new Personna(mike, “Peter”);

new Personna(mike, “Bobby”);

new Personna(carol, “Marcia”);

new Personna(carol, “Jan”);

new Personna(carol, “Cindy”);

Personna *alice=new Personna(0, “Alice”);

new Personna(alice, “King”);

new Personna(alice, “Queen”);

cout << ”\nDisplay the list using QObject::dumpObjectTree()” << endl;

bunch.dumpObjectTree();

QDebug(&QString(” QDebug() called!”));

showTree(&bunch);

showTree(alice);

cout << ”\nProgram finished – destroy all objects.” << endl;
//alice leaks on purpose
return 0;

@

  1.c) Personna.cpp

@

  /*
  * Personna.cpp * * Created on: Sep 14, 2010 * Author: ben */

  #include “Personna.h”


  static QTextStream cout(stdout, QIODevice::WriteOnly);


  Personna::Personna(QObject* parent, QString name)
  : QObject(parent) { 

            setObjectName(name); 

            cout << QString(“Constructing Person: %1”).arg(name) << endl;


  }


  Personna::~Personna() { 

             cout << QString(“Destroying Person: %1”).arg(objectName()) << endl;


  }

@
1.d) Personna.h
@

  /* * Personna.h * * Created on: Sep 14, 2010 * Author: ben */

  #ifndef PERSONNA_H_

  #define PERSONNA_H_



  class Personna : public QObject{


  public:


  Personna(QObject* parent, QString name);

virtual ~Personna();

  };

  #endif /* PERSONNA_H_ */

@
2)Below is the .pro file I used with QtCreator(latest linux binary release) (The cpp/h files are the same as above):

@

  #————————————————————————-

  #Project created by QtCreator 2010-09-15T00:42:26

  #

  #————————————————————————-

  QT += core

  QT -= gui

  TARGET = qobj
  CONFIG += console
  CONFIG -= app_bundle
  CONFIG += debug

  TEMPLATE = app

  SOURCES += main.cpp \
  personna.cpp

  HEADERS += \
  personna.h

@

tokyoben

This is the output I get:

@
First we create a bunch of objects.
Constructing Person: A Stack Object
Constructing Person: Mike
Constructing Person: Carol
Constructing Person: Greg
Constructing Person: Peter
Constructing Person: Bobby
Constructing Person: Marcia
Constructing Person: Jan
Constructing Person: Cindy
Constructing Person: Alice
Constructing Person: King
Constructing Person: Queen

Display the list using QObject::dumpObjectTree()
Member: Mike - Parent:A Stack Object
Member: Greg - Parent:Mike
Member: Peter - Parent:Mike
Member: Bobby - Parent:Mike
Member: Carol - Parent:A Stack Object
Member: Marcia - Parent:Carol
Member: Jan - Parent:Carol
Member: Cindy - Parent:Carol
Member: King - Parent:Alice
Member: Queen - Parent:Alice

Program finished - destroy all objects.
Destroying Person: A Stack Object
Destroying Person: Mike
Destroying Person: Greg
Destroying Person: Peter
Destroying Person: Bobby
Destroying Person: Carol
Destroying Person: Marcia
Destroying Person: Jan
Destroying Person: Cindy

@

viswesr

I get the following correct output:
@
First we create a bunch of objects.
Constructing Person: A Stack Object
Constructing Person: Mike
Constructing Person: Carol
Constructing Person: Greg
Constructing Person: Peter
Constructing Person: Bobby
Constructing Person: Marcia
Constructing Person: Jan
Constructing Person: Cindy
Constructing Person: Alice
Constructing Person: King
Constructing Person: Queen

Display the list using QObject::dumpObjectTree()
Member: Mike - Parent:A Stack Object
Member: Greg - Parent:Mike
Member: Peter - Parent:Mike
Member: Bobby - Parent:Mike
Member: Carol - Parent:A Stack Object
Member: Marcia - Parent:Carol
Member: Jan - Parent:Carol
Member: Cindy - Parent:Carol
Member: King - Parent:Alice
Member: Queen - Parent:Alice

Program finished – destroy all objects.
Destroying Person: A Stack Object
Destroying Person: Mike
Destroying Person: Greg
Destroying Person: Peter
Destroying Person: Bobby
Destroying Person: Carol
Destroying Person: Marcia
Destroying Person: Jan
Destroying Person: Cindy
QObject::A Stack Object
QObject::Mike
QObject::Greg
QObject::Peter
QObject::Bobby
QObject::Carol
QObject::Marcia
QObject::Jan
QObject::Cindy

@

Can you install 4.7.0 RC1 binary from the above links and try?

tokyoben

I tried with 4.7.0 RC1 binary and it didn't work. Below is my hand altered Makefile where I pointed everything to the newly installed Qt.

@
#############################################################################

Makefile for building: qobject

Generated by qmake (2.01a) (Qt 4.5.2) on: Thu Sep 16 08:14:35 2010

Project: qobject.pro

Template: app

Command: /usr/bin/qmake -unix -o Makefile qobject.pro

#############################################################################

####### Compiler, tools and options

CC = gcc
CXX = g++
DEFINES = -DQT_DEBUG -DQT_CORE_LIB
CFLAGS = -pipe -O2 -Wall -W -D_REENTRANT $(DEFINES)
CXXFLAGS = -pipe -O2 -Wall -W -D_REENTRANT $(DEFINES)
INCPATH = -I/home/ben/Qt/qtsdk-2010.05/qt/mkspecs/linux-g++ -I. -I../../../Qt/qtsdk-2010.05/qt/include/QtCore -I/usr/include/qt4 -I. -I../../../Qt/qtsdk-2010.05/qt/include -I.
LINK = g++
LFLAGS = -Wl,-O1
LIBS = $(SUBLIBS) -L/home/ben/Qt/qtsdk-2010.05/lib -lQtCore -lpthread
AR = ar cqs
RANLIB =
QMAKE = /home/ben/Qt/qtsdk-2010.05/qt/bin/qmake
TAR = tar -cf
COMPRESS = gzip -9f
COPY = cp -f
SED = sed
COPY_FILE = $(COPY)
COPY_DIR = $(COPY) -r
INSTALL_FILE = install -m 644 -p
INSTALL_DIR = $(COPY_DIR)
INSTALL_PROGRAM = install -m 755 -p
DEL_FILE = rm -f
SYMLINK = ln -sf
DEL_DIR = rmdir
MOVE = mv -f
CHK_DIR_EXISTS= test -d
MKDIR = mkdir -p

####### Output directory

OBJECTS_DIR = ./

####### Files

SOURCES = main.cpp
Personna.cpp
OBJECTS = main.o
Personna.o
DIST = /home/ben/Qt/qtsdk-2010.05/qt/mkspecs/common/g++.conf
/home/ben/Qt/qtsdk-2010.05/qt/mkspecs/common/unix.conf
/home/ben/Qt/qtsdk-2010.05/qt/mkspecs/common/linux.conf
/home/ben/Qt/qtsdk-2010.05/qt/mkspecs/qconfig.pri
......
/home/ben/Qt/qtsdk-2010.05/qt/mkspecs/features/lex.prf
/home/ben/Qt/qtsdk-2010.05/qt/mkspecs/features/include_source_dir.prf
qobject.pro
QMAKE_TARGET = qobject
DESTDIR =
TARGET = qobject

......

####### Build rules

all: Makefile $(TARGET)

$(TARGET): $(OBJECTS)
$(LINK) $(LFLAGS) -o $(TARGET) $(OBJECTS) $(OBJCOMP) $(LIBS)

Makefile: qobject.pro /home/ben/Qt/qtsdk-2010.05/qt/mkspecs/linux-g++/qmake.conf /home/ben/Qt/qtsdk-2010.05/qt/mkspecs/common/g++.conf
/home/ben/Qt/qtsdk-2010.05/qt/mkspecs/common/unix.conf
/home/ben/Qt/qtsdk-2010.05/qt/mkspecs/common/linux.conf
/home/ben/Qt/qtsdk-2010.05/qt/mkspecs/qconfig.pri
/home/ben/Qt/qtsdk-2010.05/qt/mkspecs/features/qt_functions.prf
......
/home/ben/Qt/qtsdk-2010.05/qt/mkspecs/features/lex.prf
/home/ben/Qt/qtsdk-2010.05/qt/mkspecs/features/include_source_dir.prf
/home/ben/Qt/qtsdk-2010.05/qt/lib/libQtGui.prl
/home/ben/Qt/qtsdk-2010.05/qt/lib/libQtCore.prl
$(QMAKE) -unix -o Makefile qobject.pro
/home/ben/Qt/qtsdk-2010.05/qt/mkspecs/common/g++.conf:
/home/ben/Qt/qtsdk-2010.05/qt/mkspecs/common/unix.conf:
/home/ben/Qt/qtsdk-2010.05/qt/mkspecs/common/linux.conf:
/home/ben/Qt/qtsdk-2010.05/qt/mkspecs/qconfig.pri:
......
/home/ben/Qt/qtsdk-2010.05/qt/mkspecs/features/lex.prf:
/home/ben/Qt/qtsdk-2010.05/qt/mkspecs/features/include_source_dir.prf:
/home/ben/Qt/qtsdk-2010.05/qt/lib/libQtGui.prl:
/home/ben/Qt/qtsdk-2010.05/qt/lib/libQtCore.prl:
qmake: FORCE
@$(QMAKE) -unix -o Makefile qobject.pro

dist:
@$(CHK_DIR_EXISTS) .tmp/qobject1.0.0 || $(MKDIR) .tmp/qobject1.0.0
$(COPY_FILE) --parents $(SOURCES) $(DIST) .tmp/qobject1.0.0/ && $(COPY_FILE) --parents Personna.h .tmp/qobject1.0.0/ && $(COPY_FILE) --parents main.cpp Personna.cpp .tmp/qobject1.0.0/ && (cd dirname .tmp/qobject1.0.0 && $(TAR) qobject1.0.0.tar qobject1.0.0 && $(COMPRESS) qobject1.0.0.tar) && $(MOVE) dirname .tmp/qobject1.0.0/qobject1.0.0.tar.gz . && $(DEL_FILE) -r .tmp/qobject1.0.0

clean:compiler_clean
-$(DEL_FILE) $(OBJECTS)
-$(DEL_FILE) *~ core *.core

####### Sub-libraries

distclean: clean
-$(DEL_FILE) $(TARGET)
-$(DEL_FILE) Makefile

mocclean: compiler_moc_header_clean compiler_moc_source_clean

mocables: compiler_moc_header_make_all compiler_moc_source_make_all

compiler_moc_header_make_all:
compiler_moc_header_clean:
compiler_rcc_make_all:
compiler_rcc_clean:
compiler_image_collection_make_all: qmake_image_collection.cpp
compiler_image_collection_clean:
-$(DEL_FILE) qmake_image_collection.cpp
compiler_moc_source_make_all:
compiler_moc_source_clean:
compiler_uic_make_all:
compiler_uic_clean:
compiler_yacc_decl_make_all:
compiler_yacc_decl_clean:
compiler_yacc_impl_make_all:
compiler_yacc_impl_clean:
compiler_lex_make_all:
compiler_lex_clean:
compiler_clean:

####### Compile

main.o: main.cpp Personna.h
$(CXX) -c $(CXXFLAGS) $(INCPATH) -o main.o main.cpp

Personna.o: Personna.cpp Personna.h
$(CXX) -c $(CXXFLAGS) $(INCPATH) -o Personna.o Personna.cpp

####### Install

install: FORCE

uninstall: FORCE

FORCE:

@