My system is running Ubuntu 16.04 LTS.I seem to have installed Qt in two places. 4.8.7 is installed in /usr and 5.5.1 is installed in my home directory for reasons which probably seemed sensible at the time.$ /usr/bin/qmake -vQMake version 2.01aUsing Qt version 4.8.7 in /usr/lib/x86_64-linux-gnu$ ~/Qt/5.5/gcc_64/bin/qmake -vQMake version 3.0Using Qt version 5.5.1 in /home/jsd/Qt/5.5/gcc_64/lib$ which qmake/usr/bin/qmakeQt Creator sees the home-directory version and thinks it's running 5.5.1, but when it runs qmake in the build process it runs the 4.8.7 version and minor annoyances follow.How can I clean this up? Also, is it normal for Qt to be installed in my home directory?Edit: The reason this was an issue is Qt Creator was ignoring CONFIG += c++14 and refusing to allow C++14 syntax like auto foo = [](const a, const b){return a<b;}; when compiling with Clang 3.7, which should support C++14. qmake only supported CONFIG += c++14 since 5.4 hence I thought the problem was my old qmake version.
Qt installed in two places; wrong one takes precedence
ubuntu;software installation;debian installer;qt;qtcreator
I found the solution:remove Qt4 via the package managerinstall Qt5 via the package managerdelete Qt from the home folderqtcreator still ignores CONFIG += C++14 when compiling with Clang ( Edit usr/lib/x64_84-linux-gnu/qt5/mkspecs/features/c++14.prf and comment out the guards intended to only apply -std=c++1y to Clang 3.2 and higher (which seem to be applying despite only having Clang 3.7 installed)Modified c++14.prf file:intel_icc {    # ICC does not support C++14 yet} else: clang {#    # Clang has supported -std=c++1y since version 3.2#    greaterThan(QT_CLANG_MAJOR_VERSION, 3)|greaterThan(QT_CLANG_MINOR_VERSION, 1): \        QMAKE_CXXFLAGS_CXX11 = -std=c++14#    # Unknown how long Apple Clang has supported -std=c++1y, but at least since XCode 5.0#    greaterThan(QT_APPLE_CLANG_MAJOR_VERSION, 4): \#        QMAKE_CXXFLAGS_CXX11 = -std=c++1y} else: gcc {    # GCC has supported -std=c++1y since 4.8    greaterThan(QT_GCC_MAJOR_VERSION, 4)|greaterThan(QT_GCC_MINOR_VERSION, 7): \        QMAKE_CXXFLAGS_CXX11 = -std=c++1y}# Delegate to c++11.prfinclude(c++11.prf)