source: trunk/doc/src/development/debug.qdoc@ 730

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/*!
    \page debug.html
    \title Debugging Techniques

    Here we present some useful hints to help you with debugging your
    Qt-based software.

    \tableofcontents

    \section1 Configuring Qt for Debugging

    When \l{Installation}{configuring Qt for installation}, it is possible
    to ensure that it is built to include debug symbols that can make it
    easier to track bugs in applications and libraries. However, on some
    platforms, building Qt in debug mode will cause applications to be larger
    than desirable.

    \section2 Debugging in Mac OS X and Xcode

    \section3 Debugging With/Without Frameworks

    The basic stuff you need to know about debug libraries and
    frameworks is found at developer.apple.com in: 
    \l{http://developer.apple.com/technotes/tn2004/tn2124.html#SECDEBUGLIB}
    {Apple Technicle Note TN2124} Qt follows that. 

    When you build Qt, frameworks are built by default, and inside the
    framework you will find both a release and a debug version (e.g.,
    QtCore and QtCore_debug). If you pass the \c{-no-framework} flag
    when you build Qt, two dylibs are built for each Qt library (e.g.,
    libQtCore.4.dylib and libQtCore_debug.4.dylib).

    What happens when you link depends on whether you use frameworks
    or not. We don't see a compelling reason to recommend one over the
    other.

    \section4 With Frameworks:

    Since the release and debug libraries are inside the framework,
    the app is simply linked against the framework. Then when you run
    in the debugger, you will get either the release version or the
    debug version, depending on whether you set \c{DYLD_IMAGE_SUFFIX}.
    If you don't set it, you get the release version by default (i.e.,
    non _debug). If you set \c{DYLD_IMAGE_SUFFIX=_debug}, you get the
    debug version.

    \section4 Without Frameworks:

    When you tell \e{qmake} to generate a Makefile with the debug
    config, it will link against the _debug version of the libraries
    and generate debug symbols for the app. Running this program in
    GDB will then work like running GDB on other platforms, and you
    will be able to trace inside Qt.

    \section3 Debug Symbols and Size