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std::thread run time error "Enable multithreading to use std::thread: Operation not permitted"

  • I am trying to port a program that was running without any problem when the environment set up was
    Ubuntu 12.0
    QTCreator Version - 2.4.1
    QT - 4.8.0
    gcc - 4.6.3 to a new environment

    Ubuntu 14.04
    QTCreator Version - 3.0.1
    QT - 5.2.1
    gcc - 4.8

    Unfortunately I end up seeing a runtime error "terminate called after throwing an instance of 'std::system_error' what(): Enable multithreading to use std::thread:Operation not permitted"

    As per my understanding this seems to be an issue with compiler compatibility. Either I miss some options during compilations or a bug from compiler.

    How to get his fixed? Any help is greatly appreciated.

  • Hi, and welcome to the Qt forum!
    That's a bug in the Ubuntu gcc package, see here. As a workaround it's suggested to add the following compiler flags: -Wl,--no-as-needed

  • @Wieland Thank you very much for the reply. I have tried that and still see the same issue. Please find my compile output. Any issue with the compiler options?

    ++ -c -pipe -std=c++11 -pthread -O2 -Wall -W -D_REENTRANT -fPIE -DQT_NO_DEBUG -DQT_GUI_LIB -DQT_CORE_LIB -I/usr/lib/i386-linux-gnu/qt5/mkspecs/linux-g++ -I../SimulatorSiteControl -I/usr/include/qt5 -I/usr/include/qt5/QtGui -I/usr/include/qt5/QtCore -I. -I. -o map.o ../SimulatorSiteControl/Map/map.cpp
    g++ -Wl,-O1 -o SimulatorSimulatorSiteControl main.o simulator.o map.o cbmapnotification.o notifymapactivestate.o -lQt5Gui -L/usr/lib/i386-linux-gnu -lQt5Core -lGL -lpthread

  • Are you using qmake for this? How did you add the suggested compiler options?

  • Moderators

    It can't be qmake, as in my experience qmake generates the make compile lines with -fPIC and doesn't rely on the "position independent executable" option in g++. Also switching from one optimization level to the other between compiler and linker is odd ...

  • @Wieland, @kshegunov ,

    Its qmake as per my understanding. I tried adding QMAKE_CXXFLAGS += -Wl,--no-as-needed and CONFIG += -Wl,--no-as-needed in .pro file. Both options generate the same output.
    Please find compiler output
    11:22:41: Running steps for project SimulatorSimulatorSiteControl...
    11:22:41: Starting: "/usr/lib/i386-linux-gnu/qt5/bin/qmake" /home/dhanesh/Simulator/SimulatorSiteControl/ -r -spec linux-g++ CONFIG+=declarative_debug CONFIG+=qml_debug
    11:22:41: The process "/usr/lib/i386-linux-gnu/qt5/bin/qmake" exited normally.
    11:22:41: Starting: "/usr/bin/make"

    In generated makefile I see LFLAGS = -Wl,-O1

    I still miss something and just not sure what it is.

  • Moderators

    Do you mind sharing the project file you run through qmake?

  • QMAKE_CXXFLAGS += -std=c++11 -pthread
    QMAKE_CXXFLAGS += -Wl,--no-as-needed
    TEMPLATE = app
    CONFIG += -console
    CONFIG += -qt

    SOURCES += main.cpp

    HEADERS +=

  • Moderators


    Why those lines?

    CONFIG += -console
    CONFIG += -qt

    Additionally, c++11 can be passed as config, and there's in general no need to mess with the compiler/linker flags directly. Is your application a Qt GUI or do you have a console application; do you use Qt in it, or you just use qmake and Creator as build environment?

    If you don't use Qt at all, you can try something along the lines (for a console app):

    QT -= core gui  #< No Qt libraries
    TEMPLATE = app
    CONFIG += c++11 console #< Console application with C++11 enabled (if the compiler supports it)
    CONFIG -= app_bundle
    LIBS += -lpthread   #< Although, I think this is not necessary. I think qmake links that by default
    SOURCES += ...
    HEADERS += ...

  • Thank You All. Finally I got it working. The way I passed compiler option was wrong. Once again thank you very much for the support and guidance

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