I created a simple console application in Qt. Here is source code of it:

When I use function Debug -> Start Debugging -> Start Debugging from the main menu, application runs and print the message "Hello world" to the console. But debugger ignores breakpoint set on line 6 (as you can see from the above screenshot).
Additional informations: QT Creator version - 2.4.1 QT library version - 4.8.1 (but there is also 4.7.4 installed in separate directory)
Project Build Settings are as follows:

Tool Chain settings in Tools -> Options:

GDB executable is present at directory "E:\QtSDK\pythongdb\python_2.7based" which is underlined by the fact that I have no problem debugging similarly GUI based Hello World program.
GDB settings:

Is there something I am doing wrong?
P.S. Here is my compile output:

Here is content of Makefile.debug:
#######################################################################Makefile for building: PasswordGuess
Generated by qmake (2.01a) (Qt 4.8.1) on: ne 28. 4 18:12:57 2013
Project: ..\PasswordGuess\PasswordGuess.pro
Template: app
####################################################################### # Compiler, tools and optionsCC            = gcc
CXX           = g++
DEFINES       = -DUNICODE -DQT_LARGEFILE_SUPPORT -DQT_DLL -DQT_CORE_LIB -DQT_HAVE_MMX -DQT_HAVE_3DNOW -DQT_HAVE_SSE -DQT_HAVE_MMXEXT -DQT_HAVE_SSE2 -DQT_THREAD_SUPPORT
CFLAGS        = -g -Wall $(DEFINES)
CXXFLAGS      = -g -frtti -fexceptions -mthreads -Wall $(DEFINES)
INCPATH       = -I"......\QtSDK\Desktop\Qt\4.8.1\mingw\include\QtCore" -I"......\QtSDK\Desktop\Qt\4.8.1\mingw\include" -I"......\QtSDK\Desktop\Qt\4.8.1\mingw\include\ActiveQt" -I"debug" -I"..\PasswordGuess" -I"." -I"......\QtSDK\Desktop\Qt\4.8.1\mingw\mkspecs\win32-g++"
LINK        =        g++
LFLAGS        =        -Wl,-subsystem,console -mthreads
LIBS        =        -L"e:\QtSDK\Desktop\Qt\4.8.1\mingw\lib" -lQtCored4
QMAKE         = e:\qtsdk\desktop\qt\4.8.1\mingw\bin\qmake.exe
IDC           = e:\QtSDK\Desktop\Qt\4.8.1\mingw\bin\idc.exe
IDL           = midl
ZIP           = zip -r -9
DEF_FILE      =
RES_FILE      =
COPY          = copy /y
SED           =
COPY_FILE     = $(COPY)
COPY_DIR      = xcopy /s /q /y /i
DEL_FILE      = del
DEL_DIR       = rmdir
MOVE          = move
CHK_DIR_EXISTS= if not exist
MKDIR         = mkdir
INSTALL_FILE    = $(COPY_FILE)
INSTALL_PROGRAM = $(COPY_FILE)
INSTALL_DIR     = $(COPY_DIR)  
OBJECTS_DIR = debug
# FilesSOURCES       = ..\PasswordGuess\main.cpp
OBJECTS       = debug/main.o
DIST          =
QMAKE_TARGET  = PasswordGuess
DESTDIR        = debug\ #avoid trailing-slash linebreak
TARGET         = PasswordGuess.exe
DESTDIR_TARGET = debug\PasswordGuess.exe  
.SUFFIXES: .cpp .cc .cxx .c
.cpp.o:
    $(CXX) -c $(CXXFLAGS) $(INCPATH) -o $@ $<  
.cc.o:
    $(CXX) -c $(CXXFLAGS) $(INCPATH) -o $@ $<  
.cxx.o:
    $(CXX) -c $(CXXFLAGS) $(INCPATH) -o $@ $<  
.c.o:
    $(CC) -c $(CFLAGS) $(INCPATH) -o $@ $<  
first: all
all: Makefile.Debug  $(DESTDIR_TARGET)  
$(DESTDIR_TARGET):  $(OBJECTS)
    $(LINK) $(LFLAGS) -o $(DESTDIR_TARGET) $(OBJECTS)  $(LIBS)  
qmake:  FORCE
    @$(QMAKE) -spec ......\QtSDK\Desktop\Qt\4.8.1\mingw\mkspecs\win32-g++ CONFIG+=declarative_debug -o Makefile.Debug ..\PasswordGuess\PasswordGuess.pro  
dist:
    $(ZIP) PasswordGuess.zip $(SOURCES) $(DIST) ..\PasswordGuess\PasswordGuess.pro ......\QtSDK\Desktop\Qt\4.8.1\mingw\mkspecs\qconfig.pri ......\QtSDK\Desktop\Qt\4.8.1\mingw\mkspecs\modules\qt_webkit_version.pri ......\QtSDK\Desktop\Qt\4.8.1\mingw\mkspecs\features\qt_functions.prf ......\QtSDK\Desktop\Qt\4.8.1\mingw\mkspecs\features\qt_config.prf ......\QtSDK\Desktop\Qt\4.8.1\mingw\mkspecs\features\exclusive_builds.prf ......\QtSDK\Desktop\Qt\4.8.1\mingw\mkspecs\features\default_pre.prf ......\QtSDK\Desktop\Qt\4.8.1\mingw\mkspecs\features\win32\default_pre.prf ......\QtSDK\Desktop\Qt\4.8.1\mingw\mkspecs\features\debug.prf ......\QtSDK\Desktop\Qt\4.8.1\mingw\mkspecs\features\debug_and_release.prf ......\QtSDK\Desktop\Qt\4.8.1\mingw\mkspecs\features\default_post.prf ......\QtSDK\Desktop\Qt\4.8.1\mingw\mkspecs\features\win32\default_post.prf ......\QtSDK\Desktop\Qt\4.8.1\mingw\mkspecs\features\build_pass.prf ......\QtSDK\Desktop\Qt\4.8.1\mingw\mkspecs\features\win32\console.prf ......\QtSDK\Desktop\Qt\4.8.1\mingw\mkspecs\features\declarative_debug.prf ......\QtSDK\Desktop\Qt\4.8.1\mingw\mkspecs\features\win32\rtti.prf ......\QtSDK\Desktop\Qt\4.8.1\mingw\mkspecs\features\win32\exceptions.prf ......\QtSDK\Desktop\Qt\4.8.1\mingw\mkspecs\features\win32\stl.prf ......\QtSDK\Desktop\Qt\4.8.1\mingw\mkspecs\features\shared.prf ......\QtSDK\Desktop\Qt\4.8.1\mingw\mkspecs\features\warn_on.prf ......\QtSDK\Desktop\Qt\4.8.1\mingw\mkspecs\features\qt.prf ......\QtSDK\Desktop\Qt\4.8.1\mingw\mkspecs\features\win32\thread.prf ......\QtSDK\Desktop\Qt\4.8.1\mingw\mkspecs\features\moc.prf ......\QtSDK\Desktop\Qt\4.8.1\mingw\mkspecs\features\resources.prf ......\QtSDK\Desktop\Qt\4.8.1\mingw\mkspecs\features\uic.prf ......\QtSDK\Desktop\Qt\4.8.1\mingw\mkspecs\features\yacc.prf ......\QtSDK\Desktop\Qt\4.8.1\mingw\mkspecs\features\lex.prf ......\QtSDK\Desktop\Qt\4.8.1\mingw\mkspecs\features\include_source_dir.prf  HEADERS RESOURCES IMAGES SOURCES OBJECTIVE_SOURCES FORMS YACCSOURCES YACCSOURCES LEXSOURCES   
clean: compiler_clean
    -$(DEL_FILE) debug\main.o  
distclean: clean
    -$(DEL_FILE) $(DESTDIR_TARGET)
    -$(DEL_FILE) Makefile.Debug  
check: first
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:   
debug/main.o: ../PasswordGuess/main.cpp
    $(CXX) -c $(CXXFLAGS) $(INCPATH) -o debug\main.o ..\PasswordGuess\main.cpp  
install: FORCE
uninstall: FORCE
FORCE: