Development/Tools/Valgrind: Difference between revisions

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    Valgrind is a [[Tools|tool]] to analyze a program regarding memory leaks
    Valgrind is a [[Development/Tools|tool]] to analyze a program regarding memory leaks.
     
    == Leak Detection ==
    One of the valgrind tools is the memcheck, that can be used to detect memory leaks during the execution of an application.
     
    To do that, valgrind can be started as:
    > valgrind --tool=memcheck --leak-check=yes -v ''appname''
    where ''appname'' is the application you want to run, including its parameters, if it have to be called with any.
     
    As valgrind can produce a lot of output (and thus scroll out of your terminal), you can call valgrind redirecting its output to a file, so nothing gets lost.
    > valgrind --tool=memcheck --leak-check=yes -v ''appname'' 2>&1 | tee valgrind.log
    This will call valgrind as seen above, and will redirect all the output coming from both our application and valgrind to a file in the current directory called {{path|valgrind.log}} (of course it is possible to use any file name of the log).
     
    === Minor tweaks ===
     
    * executing valgrind with <tt>--leak-check=full</tt> instead of <tt>--leak-check=yes</tt> can give a more detailed output, especially about the found leaks
     
    * Using the <tt>--track-origins=yes</tt> flag is even slower than normal Valgrind but gives you the location where the memory used incorrectly was allocated in many situations.
     
    == References ==
    * [http://www.valgrind.org/ The Valgrind Homepage]
    * [http://www.valgrind.org/ The Valgrind Homepage]
    * [http://www.tldp.org/HOWTO/Valgrind-HOWTO/ Excellent tutorial at TLDP]
    * [http://www.tldp.org/HOWTO/Valgrind-HOWTO/ Excellent tutorial at TLDP]

    Revision as of 02:44, 16 July 2009

    Valgrind is a tool to analyze a program regarding memory leaks.

    Leak Detection

    One of the valgrind tools is the memcheck, that can be used to detect memory leaks during the execution of an application.

    To do that, valgrind can be started as:

    > valgrind --tool=memcheck --leak-check=yes -v appname
    

    where appname is the application you want to run, including its parameters, if it have to be called with any.

    As valgrind can produce a lot of output (and thus scroll out of your terminal), you can call valgrind redirecting its output to a file, so nothing gets lost.

    > valgrind --tool=memcheck --leak-check=yes -v appname 2>&1 | tee valgrind.log
    

    This will call valgrind as seen above, and will redirect all the output coming from both our application and valgrind to a file in the current directory called valgrind.log (of course it is possible to use any file name of the log).

    Minor tweaks

    • executing valgrind with --leak-check=full instead of --leak-check=yes can give a more detailed output, especially about the found leaks
    • Using the --track-origins=yes flag is even slower than normal Valgrind but gives you the location where the memory used incorrectly was allocated in many situations.

    References