Setting Up Debugger
Typically, the interaction between Qt Creator and the native debugger is set up automatically and you do not need to do anything. However, you might have an unsupported gdb version installed, your Linux environment might not have gdb installed at all, or you might want to use the debugging tools for Windows.
Note: To use the debugging tools for Windows, you must install them and add the Symbol Server provided by Microsoft to the symbol search path of the debugger. For more information, see Setting the Symbol Server in Windows.
This section explains the options you have for debugging C++ code and provides installation notes for the supported native debuggers.
Supported Native Debugger Versions
The debugger plugin supports different builds of the gdb debugger, both with and without the ability to use Python scripting. The Python enabled versions are preferred, but they are not available on Mac and on older versions of Linux. On Windows, Symbian, and Maemo, only the Python version is supported.
The non-Python versions use the compiled version of the debugging helpers, that you must enable separately. For more information, see Debugging Helper Library with C++.
The Python version uses a script version of the debugging helpers that does not need any special setup.
The CDB native debugger has similar funtionality to the non-Python gdb debugger engine. Specifically, it also uses compiled C++ code for the debugging helper library.
The following table summarizes the support for debugging C++ code:
|Platform||Compiler||Native Debugger||Python||Debugger Modes|
Term, Plain, Attach (with Python, only), Remote
Term, Plain, Attach, Remote
Term, Plain, Attach
Term, Plain, Attach, Remote
Microsoft Visual C++ Compiler
Debugging Tools for Windows/CDB
Term, Plain, Attach, Post-Mortem
Installing Native Debuggers
There are various reasons why the debugger plugin may fail to automatically pick up a suitable native debugger. The native debugger might be missing (which is usually the case for the CDB debugger on Windows which always needs to be installed manually by the user) or the installed version is not supported. Check the table below for the supported versions and other important information about installing native debuggers.
On Linux, install version 6.8, 7.0.1 (version 7.0 is not supported), 7.1, or later. On Mac OS X, install Apple gdb version 6.3.50-20050815 (build 1344) or later.
Debugging tools for Windows
Using this engine requires you to install the Debugging tools for Windows 32-bit or 64-bit package (Version 126.96.36.1994 for the 32-bit or the 64-bit version of Qt Creator, respectively), which is freely available for download from the Microsoft Developer Network.
Note: Visual Studio does not include the Debugging tools needed, and therefore, you must install them separately.
The pre-built Qt SDK for Windows makes use of the library if it is present on the system. When manually building Qt Creator using the Microsoft Visual C++ Compiler, the build process checks for the required files in "%ProgramFiles%\Debugging Tools for Windows".
It is highly recommended that you add the Symbol Server provided by Microsoft to the symbol search path of the debugger. The Symbol Server provides you with debugging informaton for the operating system libraries for debugging Windows applications. For more information, see Setting the Symbol Server in Windows.
Debugging tools for Mac OS X
The Qt binary distribution contains both debug and release variants of the libraries. But you have to explicitly tell the runtime linker that you want to use the debug libraries even if your application is compiled as debug as release is the default library.
If you use a qmake based project in Qt Creator, you can set a flag in your run configuration, in Projects mode. In the run configuration, select Use debug version of frameworks.
For more detailed information about debugging on the Mac, see: http://developer.apple.com/mac/library/technotes/tn2004/tn2124.html
Note: The Mac OS X Snow Leopard (10.6) has a bug, that can be worked around as described in the link provided below: http://bugreports.qt.nokia.com/browse/QTBUG-4962.
Setting the Symbol Server in Windows
To obtain debugging information for the operating system libraries for debugging Windows applications, add the Symbol Server provided by Microsoft to the symbol search path of the debugger:
- Select Tools > Options... > Debugger > Cdb.
- In the Symbol paths field, open the Insert... menu and select Symbol Server....
- Select a directory where you want to store the cached information and click OK.
Use a subfolder in a temporary directory, such as C:\temp\symbolcache.
Note: Populating the cache might take a long time on a slow network connection.