构建简单的Qt5应用程序时出错

Question

I installed Qt 5.0.0 ( qt-mac-opensource-5.0.0-clang-offline.dmg ) on a Mac OS X 10.7.5 and now I'm trying to compile a " Hello World " application using Qt Creator 2.6.1 .

The build process complains about a directory not found: /Users/karlphillip/Qt5.0.0/5.0.0/clang_64/qtbase/lib , followed by several linking errors:

clang++ -c -pipe -mmacosx-version-min=10.6 -O2 -Wall -W -fPIE -DQT_NO_DEBUG -DQT_GUI_LIB -DQT_CORE_LIB -I/Users/karlphillip/Qt5.0.0/5.0.0/clang_64/mkspecs/macx-clang -I. -I/Users/karlphillip/Qt5.0.0/5.0.0/clang_64/include -I/Users/karlphillip/Qt5.0.0/5.0.0/clang_64/include/QtGui -I/Users/karlphillip/Qt5.0.0/5.0.0/clang_64/lib/QtGui.framework/Versions/5/Headers -I/Users/karlphillip/Qt5.0.0/5.0.0/clang_64/include/QtCore -I/Users/karlphillip/Qt5.0.0/5.0.0/clang_64/lib/QtCore.framework/Versions/5/Headers -I. -I/System/Library/Frameworks/OpenGL.framework/Versions/A/Headers -I/System/Library/Frameworks/AGL.framework/Headers -o main.o main.cpp
clang++ -headerpad_max_install_names -mmacosx-version-min=10.6 -o hello_qt.app/Contents/MacOS/hello_qt main.o -F/Users/karlphillip/Qt5.0.0/5.0.0/clang_64/lib -framework QtGui -F/Users/karlphillip/Qt5.0.0/5.0.0/clang_64/qtbase/lib -framework QtCore -framework OpenGL -framework AGL
ld: warning: directory not found for option '-F/Users/karlphillip/Qt5.0.0/5.0.0/clang_64/qtbase/lib'
Undefined symbols for architecture x86_64:
"QApplication::QApplication(int&, char**, int)", referenced from:
_main in main.o
"QLabel::QLabel(QString const&, QWidget*, QFlags<Qt::WindowType>)", referenced from:
_main in main.o
"QWidget::show()", referenced from:
_main in main.o
"QPushButton::QPushButton(QString const&, QWidget*)", referenced from:
_main in main.o
"QApplication::exec()", referenced from:
_main in main.o
"QPushButton::~QPushButton()", referenced from:
_main in main.o
"QLabel::~QLabel()", referenced from:
_main in main.o
"QApplication::~QApplication()", referenced from:
_main in main.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make: *** [hello_qt.app/Contents/MacOS/hello_qt] Error 1

It's important to note that the path /Users/karlphillip/Qt5.0.0/5.0.0/clang_64/qtbase/lib is not valid because the directory qtbase doesn't exist. The working path is /Users/karlphillip/Qt5.0.0/5.0.0/clang_64/lib . I'm not referring to qtbase anywhere in my project, so this is probably being added by qmake .

Answer 1

As it turns out, the invalid qtbase path thing is really a Qt bug originally reported at QTBUG-28336 .

The linking problem is due to my project not linking with QtWidgets , which is something we are going to have to do starting in Qt5. This is accomplished by adding the following line to your .pro file:

QT += widgets

Answer 2

i had the same problem and to be honest im not shure how i managed it to solve.

i think/guess i copied the needed folders from the sources into the matching 'clang_64' folders and that does the job.

soo long zai