cannot find -lqwt-qt5 error

justdad

I am in the process of taking over a Raspberry pi project who's developer left. Its runing on raspberrian legacy. I am a linux novice. I have been able to get almost all of the tool chain working except for linking in qwt. When I go to make the project I get the error "/usr/bin/ld: cannot find -lqwt-qt5" shown below.

Below that is the make file. It seems that it wants the qwt libraries in /usr/lib which is where I put them with the qwtconfig.pri

The top part of the make file is shown below. It shows that its trying to access the library -L$(SYSROOT)/usr/lib/ -lqwt-qt5 but it can not find it. Once I changed the install path to /usr/lib, it put the qwt lib files in this directory but I do not see a "qwt-qt5" type of file(also listed below). What am I doing wrong here? Where do I get the library file qwt-qt5?

Ken

Error:

pi@raspberrypi:~/Desktop/Double_Die $ make VERBOSE=1
g++ -Wl,-O1 -o Double main.o deuce.o debug.o xml.o config_xml.o tab_rdo.o tab.o tab_prf_rng.o keyboard.o tab_prf_stp.o tab_prf.o storage.o file_data.o file_linearity.o profile_xml.o ...  moc_tab_lin_plt.o moc_tab_plt.o moc_status.o moc_tab_prf_pup.o moc_ktsstyle.o moc_login.o moc_thread_tvc.o moc_tab_prf_box.o moc_tab_tst.o moc_tab_prf_oep.o moc_Password.o   -L/usr/lib/ -lqwt-qt5 -L/usr/local/lib/ -lwiringPi -lQt5Widgets -lQt5Gui -lQt5SerialPort -lQt5Core -lGLESv2 -lpthread -latomic
/usr/bin/ld: cannot find -lqwt-qt5
collect2: error: ld returned 1 exit status
make: *** [Makefile:343: Double] Error 1

MAKEFILE

#############################################################################
# Makefile for building: Deuce
# Generated by qmake (3.1) (Qt 5.11.3)
# Project:  Deuce.pro
# Template: app
# Command: /usr/lib/qt5/bin/qmake -o Makefile Deuce.pro -spec linux-g++ CONFIG+=debug CONFIG+=qml_debug
#############################################################################

MAKEFILE      = Makefile

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

CC            = gcc
CXX           = g++
DEFINES       = -DQT_DEPRECATED_WARNINGS -DQT_QML_DEBUG -DQT_WIDGETS_LIB -DQT_GUI_LIB -DQT_SERIALPORT_LIB -DQT_CORE_LIB
CFLAGS        = -pipe -g -Wall -W -D_REENTRANT -fPIC $(DEFINES)
CXXFLAGS      = -pipe -g -Wall -W -D_REENTRANT -fPIC $(DEFINES)
INCPATH       = -I. -I$(SYSROOT)/usr/include/qwt -I$(SYSROOT)/usr/include/ -I/home/pi/Desktop/Double_Die/../../../../../../qwt-6.2.0 -I/home/pi/Desktop/Double_Die/../../../../../../qwt-6.2.0/src -I/home/pi/Desktop/Double_Die/../../../../../../WiringPi-master/wiringPi -isystem /usr/include/arm-linux-gnueabihf/qt5 -isystem /usr/include/arm-linux-gnueabihf/qt5/QtWidgets -isystem /usr/include/arm-linux-gnueabihf/qt5/QtGui -isystem /usr/include/arm-linux-gnueabihf/qt5/QtSerialPort -isystem /usr/include/arm-linux-gnueabihf/qt5/QtCore -I. -I/usr/lib/arm-linux-gnueabihf/qt5/mkspecs/linux-g++
QMAKE         = /usr/lib/qt5/bin/qmake
DEL_FILE      = rm -f
CHK_DIR_EXISTS= test -d
MKDIR         = mkdir -p
COPY          = cp -f
COPY_FILE     = cp -f
COPY_DIR      = cp -f -R
INSTALL_FILE  = install -m 644 -p
INSTALL_PROGRAM = install -m 755 -p
INSTALL_DIR   = cp -f -R
QINSTALL      = /usr/lib/qt5/bin/qmake -install qinstall
QINSTALL_PROGRAM = /usr/lib/qt5/bin/qmake -install qinstall -exe
DEL_FILE      = rm -f
SYMLINK       = ln -f -s
DEL_DIR       = rmdir
MOVE          = mv -f
TAR           = tar -cf
COMPRESS      = gzip -9f
DISTNAME      = Deuce1.0.0
DISTDIR = /home/pi/Desktop/Double_Die/.tmp/Deuce1.0.0
LINK          = g++
LFLAGS        = 
LIBS          = $(SUBLIBS) -L$(SYSROOT)/usr/lib/ -lqwt-qt5 -L$(SYSROOT)/usr/local/lib/ -lwiringPi -lQt5Widgets -lQt5Gui -lQt5SerialPort -lQt5Core -lGLESv2 -lpthread -latomic 
AR            = ar cqs
RANLIB        = 
SED           = sed
STRIP         = strip

qwtconfig.pri

################################################################
# Qwt Widget Library
# Copyright (C) 1997   Josef Wilgen
# Copyright (C) 2002   Uwe Rathmann
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the Qwt License, Version 1.0
################################################################

QWT_VER_MAJ      = 6
QWT_VER_MIN      = 2
QWT_VER_PAT      = 0
QWT_VERSION      = $${QWT_VER_MAJ}.$${QWT_VER_MIN}.$${QWT_VER_PAT}

######################################################################
# Install paths
######################################################################

QWT_INSTALL_PREFIX = $$[QT_INSTALL_PREFIX]

unix {
    QWT_INSTALL_PREFIX    = /usr/lib
    # QWT_INSTALL_PREFIX = /usr/local/qwt-$$QWT_VERSION-qt-$$QT_VERSION
    #QWT_INSTALL_PREFIX    = /usr/local/qwt-$$QWT_VERSION
}

win32 {
    QWT_INSTALL_PREFIX    = C:/Qwt-$$QWT_VERSION
    # QWT_INSTALL_PREFIX = C:/Qwt-$$QWT_VERSION-qt-$$QT_VERSION
}

QWT_INSTALL_DOCS      = $${QWT_INSTALL_PREFIX}/doc
QWT_INSTALL_HEADERS   = $${QWT_INSTALL_PREFIX}/include
QWT_INSTALL_LIBS      = $${QWT_INSTALL_PREFIX}

Partial Directory of /usr/lib

cups                 libpigpio.so.1                        python3
dbus-1.0             libpyglib-2.0-python2.7.so.0          python3.7
dconf                libpyglib-2.0-python2.7.so.0.0.0      qpdfview
debug                libpypy-c.so                          qt5
dhcpcd               libqmi                                raspberrypi-sys-mods
dhcpcd5              libqwt.so                             raspi-config
doc                  libqwt.so.6                           rc-gui
dpkg                 libqwt.so.6.2                         resolvconf
eject                libqwt.so.6.2.0

jsulm

@justdad Did you build qwt for RaspberryPi?

justdad

I followed the directions given here. (https://qwt.sourceforge.io/qwtinstall.html) On the raspberry pi 3

From within the qwt-620 directory I used the commands

qmake qwt.pro

make

sudo make install

justdad

Fixed dir name...

I followed the directions given here. (https://qwt.sourceforge.io/qwtinstall.html) On the raspberry pi 3

From within the qwt-6.2.0 directory I used the commands

qmake qwt.pro

make

sudo make install

jsulm

@justdad Please show your pro file

justdad

@jsulm

Here is the full pro file.

#-------------------------------------------------
#
# Project created by QtCreator 2019-04-23T16:28:20
#
#-------------------------------------------------

QT       += core gui serialport

greaterThan(QT_MAJOR_VERSION, 4): QT += widgets

TARGET = Deuce
TEMPLATE = app

DEFINES += QT_DEPRECATED_WARNINGS

LIBS += -L$(SYSROOT)/usr/lib/ -lqwt-qt5 -L$(SYSROOT)/usr/local/lib/ -lwiringPi
INCLUDEPATH += $(SYSROOT)/usr/include/qwt $(SYSROOT)/usr/include/

SOURCES += main.cpp\
        deuce.cpp \
    debug.cpp \
    xml.cpp \
    config_xml.cpp \
    tab_rdo.cpp \
    tab.cpp \
    tab_prf_rng.cpp \
    keyboard.cpp \
    tab_prf_stp.cpp \
    tab_prf.cpp \
    storage.cpp \
    file_data.cpp \
    file_linearity.cpp \
    profile_xml.cpp \
    tab_cfg.cpp \
    tab_ctl.cpp \
    thread_dev.cpp \
    timer_com.cpp \
    tab_lin_ctl.cpp \
    tab_dia.cpp \
    tab_img.cpp \
    tab_iro.cpp \
    tab_lin_plt.cpp \
    tab_plt.cpp \
    status.cpp \
    tab_prf_pup.cpp \
    ktsstyle.cpp \
    login.cpp \
    thread_tvc.cpp \
    serialport.cpp \
    tab_prf_box.cpp \
    tab_tst.cpp \
    tab_prf_oep.cpp \
    password.cpp

HEADERS  += deuce.h \
    include.h \
    define.h \
    debug.h \
    struct.h \
    xml.h \
    config_xml.h \
    tab_rdo.h \
    tab.h \
    tab_prf_rng.h \
    keyboard.h \
    tab_prf_stp.h \
    tab_prf.h \
    storage.h \
    file_data.h \
    file_linearity.h \
    profile_xml.h \
    tab_cfg.h \
    tab_ctl.h \
    thread_dev.h \
    timer_com.h \
    tab_lin_ctl.h \
    tab_dia.h \
    tab_img.h \
    tab_iro.h \
    tab_lin_plt.h \
    tab_plt.h \
    status.h \
    tab_prf_pup.h \
    ktsstyle.h \
    login.h \
    thread_tvc.h \
    serialport.h \
    tab_prf_box.h \
    tab_tst.h \
    tab_prf_oep.h \
    password.h

mchinand

It looks like your project file is expecting that the qwt library has been built with its TARGET variable in its project file (I think it's actually the src/src.pro project file) set to 'qwt-qt$${QT_VERSION}. You could probably just remove the '-qt5' from the LIBS line in your project file but if you are considering upgrading to Qt6, you probably want to build qwt so that it includes the Qt version in the lib filenames (and update your .pro file so the Qt version part of the Qwt library uses the $${QT_VERSION} variable and instead of a fixed version string). Then you can have Qt5 and Qt6 Qwt library files in the same directory and be able to easily switch between Qt versions for your project.

justdad

@mchinand said in cannot find -lqwt-qt5 error:

ariable and instead of a fixed version string). Then you can have Qt5 and Qt6 Qwt library files in the same directory and be able to easily switch between Qt versions for your project.

Awesome! Thanks for the help here! I would not have gone down that folder like that. So the "default" install of qwt-6.2.0 has

TARGET = $$qwtLibraryTarget(qwt)

The macro for qwtLibraryTarget(xxxxxx) looks quite involved. But your saying I should just change this to

TARGET = qt$${QT_VERSION}

I will give this a try when I get home tonight from my day job. and then also have the customer look in this folder for to verify.

Again, thank you for this information. This make a lot more sense now.

Ken

mchinand

@justdad said in cannot find -lqwt-qt5 error:

TARGET = $$qwtLibraryTarget(qwt)
The macro for qwtLibraryTarget(xxxxxx) looks quite involved. But your saying I should just change this to
TARGET = qt$${QT_VERSION}

To match what your project expects, you want a combination of both of those.

~~TARGET = $$qwtLibraryTarget(qwt)-qt$${QT_VERSION)~~

Edit: I think it should be:
TARGET = $$qwtLibraryTarget(qwt-qt$${QT_VERSION})

Add a message line to the src.pro file so you can see what it gets set to when qmake is run rather than waiting until it is built:

message("Qwt TARGET set to $${TARGET}")