compilation err in qt test program

ravi2k18

hi All,
I am beginner to qt and trying to run the below progam. however i am getting below err.

qobject.h:117:5: error: expected parameter declarator
main.cpp:1:1: note: in file included from C:\Qt-Workspace\untitled1\main.cpp:1:
main.cpp:1:10: note: in file included from C:\Qt-Workspace\untitled1\main.cpp:1:
QApplication:1:10: note: in file included from C:\win-builds\include\qt5\QtWidgets\QApplication:1:
qapplication.h:45:10: note: in file included from C:\win-builds\include\qt5\QtWidgets/qapplication.h:45:
qcoreapplication.h:48:10: note: in file included from C:\win-builds\include\qt5\QtCore/qcoreapplication.h:48:

----------------------------------

15:44:21: Running steps for project untitled1...
15:44:21: Configuration unchanged, skipping qmake step.
15:44:21: Starting: "C:\win-builds\bin\mingw32-make.exe" -j4
C:/win-builds/bin/mingw32-make -f Makefile.Debug
mingw32-make[1]: Entering directory 'C:/Qt-Workspace/build-untitled1-Desktop-Debug'
x86_64-w64-mingw32-g++ -Wl,-subsystem,windows -mthreads -o debug\name_of_the_app.exe debug/main.o  -lglu32 -lopengl32 -lgdi32 -luser32 -lmingw32 -LC:/win-builds/lib -lqtmaind -lQt5Widgetsd -lQt5Guid -lQt5Cored 
c:/win-builds/bin/../lib64/gcc/x86_64-w64-mingw32/4.8.3/../../../../x86_64-w64-mingw32/bin/ld.exe: cannot find -lqtmaind
c:/win-builds/bin/../lib64/gcc/x86_64-w64-mingw32/4.8.3/../../../../x86_64-w64-mingw32/bin/ld.exe: cannot find -lQt5Widgetsd
c:/win-builds/bin/../lib64/gcc/x86_64-w64-mingw32/4.8.3/../../../../x86_64-w64-mingw32/bin/ld.exe: cannot find -lQt5Guid
c:/win-builds/bin/../lib64/gcc/x86_64-w64-mingw32/4.8.3/../../../../x86_64-w64-mingw32/bin/ld.exe: cannot find -lQt5Cored
collect2.exe: error: ld returned 1 exit status
mingw32-make[1]: *** [debug\name_of_the_app.exe] Error 1
Makefile.Debug:77: recipe for target 'debug\name_of_the_app.exe' failed
mingw32-make[1]: Leaving directory 'C:/Qt-Workspace/build-untitled1-Desktop-Debug'
Makefile:34: recipe for target 'debug' failed
mingw32-make: *** [debug] Error 2
15:44:22: The process "C:\win-builds\bin\mingw32-make.exe" exited with code 2.
Error while building/deploying project untitled1 (kit: Desktop)
When executing step "Make"
15:44:22: Elapsed time: 00:01.

#include <QApplication>
#include <QPushButton>

int main(int argc, char **argv)
{
 QApplication app (argc, argv);

 QPushButton button ("Hello world !");
 button.show();

 return app.exec();
}

TEMPLATE = app
TARGET = name_of_the_app

QT = core gui

greaterThan(QT_MAJOR_VERSION, 4): QT += widgets

SOURCES +=  main.cpp

I have copied the above code from https://wiki.qt.io/Qt_for_Beginners#C.2B.2B_reminder
Is this because the sample code is valid for qt4 and I am running qt 5 ?
Please help me to fix the issue. so that I can continue my learning.

thanks in advance.

jsulm

@ravi2k18 This code builds perfectly fine for me with Qt 5.12 MinGW.
What Qt version do you use?

"c:/win-builds/bin/../lib64/gcc/x86_64-w64-mingw32/4.8.3/../../../../x86_64-w64-mingw32/bin/ld.exe: cannot find -lqtmaind
c:/win-builds/bin/../lib64/gcc/x86_64-w64-mingw32/4.8.3/../../../../x86_64-w64-mingw32/bin/ld.exe: cannot find -lQt5Widgetsd
c:/win-builds/bin/../lib64/gcc/x86_64-w64-mingw32/4.8.3/../../../../x86_64-w64-mingw32/bin/ld.exe: cannot find -lQt5Guid
c:/win-builds/bin/../lib64/gcc/x86_64-w64-mingw32/4.8.3/../../../../x86_64-w64-mingw32/bin/ld.exe: cannot find -lQt5Cored"

How did you install Qt? And which EXACT version?
Why do you use MinGW x86_64 4.8.3? Supported version is 7.3.

ravi2k18

i used offline installer to install qt5 qt-opensource-windows-x86-5.12.0.exe
looks like my qt creator is taking some other mingw installation dir. why so ?? when i have installed qt with dedicated mingw for this.

my QTdir is C:\win-dir while mingw 7 is installed in C:\Qt\Qt5.12.0\Tools\mingw730_64\bin
do i need specifically set the environment variables?

thanks

ravi2k18

i furthur update my build setting to refer mingw 7 but no luck

18:40:28: Running steps for project test...
18:40:28: Starting: "C:\win-builds\bin\qmake.exe" C:\Qt-Workspace\test\test.pro -spec win32-g++ "CONFIG+=debug" "CONFIG+=qml_debug"
18:40:28: The process "C:\win-builds\bin\qmake.exe" exited normally.
18:40:28: Starting: "C:\Qt\Qt5.12.0\Tools\mingw730_64\bin\mingw32-make.exe" -f C:/Qt-Workspace/Makefile qmake_all
mingw32-make: Nothing to be done for 'qmake_all'.
18:40:28: The process "C:\Qt\Qt5.12.0\Tools\mingw730_64\bin\mingw32-make.exe" exited normally.
18:40:28: Starting: "C:\Qt\Qt5.12.0\Tools\mingw730_64\bin\mingw32-make.exe" -j4
C:/Qt/Qt5.12.0/Tools/mingw730_64/bin/mingw32-make -f Makefile.Debug
mingw32-make[1]: Entering directory 'C:/Qt-Workspace'
Makefile.Debug:346: warning: overriding recipe for target 'debug/main.o'
Makefile.Debug:234: warning: ignoring old recipe for target 'debug/main.o'
x86_64-w64-mingw32-g++ -c -pipe -fno-keep-inline-dllexport -g -frtti -Wall -Wextra -fexceptions -mthreads -DUNICODE -DQT_QML_DEBUG -DQT_WIDGETS_LIB -DQT_GUI_LIB -DQT_CORE_LIB -DQT_NEEDS_QMAIN -Itest -I"..\win-builds\include\qt5" -I"..\win-builds\include\qt5\QtWidgets" -I"..\win-builds\include\qt5\QtGui" -I"..\win-builds\include\qt5\QtCore" -I"debug" -I"." -I"..\win-builds\mkspecs\win32-g++" -o debug\main.o test\main.cpp
In file included from ..\win-builds\include\qt5/QtCore/qbytearray.h:45:0,
from ..\win-builds\include\qt5/QtCore/qstring.h:46,
from ..\win-builds\include\qt5/QtCore/qcoreapplication.h:46,
from ..\win-builds\include\qt5\QtWidgets/qapplication.h:45,
from ..\win-builds\include\qt5\QtWidgets/QApplication:1,
from test\main.cpp:1:
..\win-builds\include\qt5/QtCore/qrefcount.h:58:1: warning: this use of "defined" may not be portable [-Wexpansion-to-defined]
#if QT_SUPPORTS(UNSHARABLE_CONTAINERS)
^~~~~~~~~~~~~~~~~~~~~~~~~~~
..\win-builds\include\qt5/QtCore/qrefcount.h:69:1: warning: this use of "defined" may not be portable [-Wexpansion-to-defined]
#if QT_SUPPORTS(UNSHARABLE_CONTAINERS)
^~~~~~~~~~~~~~~~~~~~~~~~~~~
..\win-builds\include\qt5/QtCore/qrefcount.h:78:1: warning: this use of "defined" may not be portable [-Wexpansion-to-defined]
#if QT_SUPPORTS(UNSHARABLE_CONTAINERS)
^~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from ..\win-builds\include\qt5/QtCore/qbytearray.h:47:0,
from ..\win-builds\include\qt5/QtCore/qstring.h:46,
from ..\win-builds\include\qt5/QtCore/qcoreapplication.h:46,
from ..\win-builds\include\qt5\QtWidgets/qapplication.h:45,
from ..\win-builds\include\qt5\QtWidgets/QApplication:1,
from test\main.cpp:1:
..\win-builds\include\qt5/QtCore/qarraydata.h:83:1: warning: this use of "defined" may not be portable [-Wexpansion-to-defined]
#if QT_SUPPORTS(UNSHARABLE_CONTAINERS)
^~~~~~~~~~~~~~~~~~~~~~~~~~~
..\win-builds\include\qt5/QtCore/qarraydata.h:104:1: warning: this use of "defined" may not be portable [-Wexpansion-to-defined]
#if QT_SUPPORTS(UNSHARABLE_CONTAINERS)
^~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from ..\win-builds\include\qt5/QtCore/qobject.h:51:0,
from ..\win-builds\include\qt5/QtCore/qcoreapplication.h:48,
from ..\win-builds\include\qt5\QtWidgets/qapplication.h:45,
from ..\win-builds\include\qt5\QtWidgets/QApplication:1,
from test\main.cpp:1:
..\win-builds\include\qt5/QtCore/qlist.h:149:1: warning: this use of "defined" may not be portable [-Wexpansion-to-defined]
#if QT_SUPPORTS(UNSHARABLE_CONTAINERS)
^~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from ..\win-builds\include\qt5/QtCore/qvariant.h:49:0,
from ..\win-builds\include\qt5/QtCore/qlocale.h:45,
from ..\win-builds\include\qt5/QtGui/qguiapplication.h:48,
from ..\win-builds\include\qt5\QtWidgets/qapplication.h:56,
from ..\win-builds\include\qt5\QtWidgets/QApplication:1,
from test\main.cpp:1:
..\win-builds\include\qt5/QtCore/qmap.h:374:1: warning: this use of "defined" may not be portable [-Wexpansion-to-defined]
#if QT_SUPPORTS(UNSHARABLE_CONTAINERS)
^~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from ..\win-builds\include\qt5/QtCore/qvariant.h:50:0,
from ..\win-builds\include\qt5/QtCore/qlocale.h:45,
from ..\win-builds\include\qt5/QtGui/qguiapplication.h:48,
from ..\win-builds\include\qt5\QtWidgets/qapplication.h:56,
from ..\win-builds\include\qt5\QtWidgets/QApplication:1,
from test\main.cpp:1:
..\win-builds\include\qt5/QtCore/qhash.h:333:1: warning: this use of "defined" may not be portable [-Wexpansion-to-defined]
#if QT_SUPPORTS(UNSHARABLE_CONTAINERS)
^~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from ..\win-builds\include\qt5/QtGui/qpolygon.h:45:0,
from ..\win-builds\include\qt5/QtGui/qmatrix.h:45,
from ..\win-builds\include\qt5/QtGui/qtransform.h:44,
from ..\win-builds\include\qt5/QtGui/qimage.h:45,
from ..\win-builds\include\qt5/QtGui/qpixmap.h:50,
from ..\win-builds\include\qt5/QtGui/qicon.h:48,
from ..\win-builds\include\qt5/QtWidgets/qabstractbutton.h:45,
from ..\win-builds\include\qt5\QtWidgets/qpushbutton.h:45,
from ..\win-builds\include\qt5\QtWidgets/QPushButton:1,
from test\main.cpp:2:
..\win-builds\include\qt5/QtCore/qvector.h:110:1: warning: this use of "defined" may not be portable [-Wexpansion-to-defined]
#if QT_SUPPORTS(UNSHARABLE_CONTAINERS)
^~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from ..\win-builds\include\qt5/QtGui/qpolygon.h:45:0,
from ..\win-builds\include\qt5/QtGui/qmatrix.h:45,
from ..\win-builds\include\qt5/QtGui/qtransform.h:44,
from ..\win-builds\include\qt5/QtGui/qimage.h:45,
from ..\win-builds\include\qt5/QtGui/qpixmap.h:50,
from ..\win-builds\include\qt5/QtGui/qicon.h:48,
from ..\win-builds\include\qt5/QtWidgets/qabstractbutton.h:45,
from ..\win-builds\include\qt5\QtWidgets/qpushbutton.h:45,
from ..\win-builds\include\qt5\QtWidgets/QPushButton:1,
from test\main.cpp:2:
..\win-builds\include\qt5/QtCore/qvector.h:334:1: warning: this use of "defined" may not be portable [-Wexpansion-to-defined]
#if QT_SUPPORTS(UNSHARABLE_CONTAINERS)
^~~~~~~~~~~~~~~~~~~~~~~~~~~
..\win-builds\include\qt5/QtCore/qvector.h:491:1: warning: this use of "defined" may not be portable [-Wexpansion-to-defined]
#if QT_SUPPORTS(UNSHARABLE_CONTAINERS)
^~~~~~~~~~~~~~~~~~~~~~~~~~~
..\win-builds\include\qt5/QtCore/qvector.h:559:1: warning: this use of "defined" may not be portable [-Wexpansion-to-defined]
#if QT_SUPPORTS(UNSHARABLE_CONTAINERS)
^~~~~~~~~~~~~~~~~~~~~~~~~~~
x86_64-w64-mingw32-g++ -Wl,-subsystem,windows -mthreads -o debug\name_of_the_app.exe debug/main.o debug/main.o -lglu32 -lopengl32 -lgdi32 -luser32 -lmingw32 -LC:/win-builds/lib -lqtmaind -lQt5Widgetsd -lQt5Guid -lQt5Cored
debug/main.o:C:\Qt-Workspace/test/main.cpp:5: multiple definition of `qMain(int, char**)'
debug/main.o:C:\Qt-Workspace/test/main.cpp:5: first defined here
C:/Qt/Qt5.12.0/Tools/mingw730_64/bin/../lib/gcc/x86_64-w64-mingw32/7.3.0/../../../../x86_64-w64-mingw32/bin/ld.exe: cannot find -lqtmaind
C:/Qt/Qt5.12.0/Tools/mingw730_64/bin/../lib/gcc/x86_64-w64-mingw32/7.3.0/../../../../x86_64-w64-mingw32/bin/ld.exe: cannot find -lQt5Widgetsd
C:/Qt/Qt5.12.0/Tools/mingw730_64/bin/../lib/gcc/x86_64-w64-mingw32/7.3.0/../../../../x86_64-w64-mingw32/bin/ld.exe: cannot find -lQt5Guid
C:/Qt/Qt5.12.0/Tools/mingw730_64/bin/../lib/gcc/x86_64-w64-mingw32/7.3.0/../../../../x86_64-w64-mingw32/bin/ld.exe: cannot find -lQt5Cored
collect2.exe: error: ld returned 1 exit status
mingw32-make[1]: *** [Makefile.Debug:79: debug\name_of_the_app.exe] Error 1
mingw32-make: *** [Makefile:34: debug] Error 2
mingw32-make[1]: Leaving directory 'C:/Qt-Workspace'
18:40:32: The process "C:\Qt\Qt5.12.0\Tools\mingw730_64\bin\mingw32-make.exe" exited with code 2.
Error while building/deploying project test (kit: Desktop)
When executing step "Make"
18:40:32: Elapsed time: 00:04.

jsulm

@ravi2k18 Why don't you just install Qt using online installer (Qt Maintenance Too if you already installed MinGW using online installer)? This is usually working out of the box (Qt + MinGW).
If you installed Qt in C:\win-dir then why do you call C:\win-builds\bin\qmake.exe ?!
Also - is your Qt for MinGW 64bit?

dheerendra

Looks like u r using different qmake than what is coming with qt install. According to ur installed qt qmake shud be from c:/Qt\Qt5.12.0\Tools\mingw730_64\bin\qmake
But I see a different directory. Can you show your build settings ? Do you see directory :\win-builds\lib with all the qt DLLs ? Looks like your mingw is 64 bit. So you have corresponding libraries ? Do you see any red mark for your kit in buld & run configuration ?

mranger90

@ravi2k18 said in compilation err in qt test program:

TEMPLATE = app
TARGET = name_of_the_app

QT = core gui

Try Qt += core gui

Note the "+="
Also remember to re-run qmake after changing the .pro file.