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Test::Valgrind - Generate suppressions, analyse and test any command with valgrind.


Version 1.19


    # From the command-line
    perl -MTest::Valgrind

    # From the command-line, snippet style
    perl -MTest::Valgrind -e 'leaky()'

    # In a test file
    use Test::More;
    eval 'use Test::Valgrind';
    plan skip_all => 'Test::Valgrind is required to test your distribution with valgrind' if $@;

    # In all the test files of a directory
    prove --exec 'perl -Iblib/lib -Iblib/arch -MTest::Valgrind' t/*.t


This module is a front-end to the Test::Valgrind::* API that lets you run Perl code through the memcheck tool of the valgrind memory debugger, to test for memory errors and leaks. If they aren't available yet, it will first generate suppressions for the current perl interpreter and store them in the portable flavour of ~/.perl/Test-Valgrind/suppressions/$VERSION. The actual run will then take place, and tests will be passed or failed according to the result of the analysis.

The complete API is much more versatile than this. By declaring an appropriate Test::Valgrind::Command class, you can run any executable (that is, not only Perl scripts) under valgrind, generate the corresponding suppressions on-the-fly and convert the analysis result to TAP output so that it can be incorporated into your project's testsuite. If you're not interested in producing TAP, you can output the results in whatever format you like (for example HTML pages) by defining your own Test::Valgrind::Action class.

Due to the nature of perl's memory allocator, this module can't track leaks of Perl objects. This includes non-mortalized scalars and memory cycles. However, it can track leaks of chunks of memory allocated in XS extensions with Newx and friends or malloc. As such, it's complementary to the other very good leak detectors listed in the "SEE ALSO" section.




Run a valgrind analysis configured by %options :

  • command => $command

    The Test::Valgrind::Command object (or class name) to use.

    Defaults to Test::Valgrind::Command::PerlScript.

  • tool => $tool

    The Test::Valgrind::Tool object (or class name) to use.

    Defaults to Test::Valgrind::Tool::memcheck.

  • action => $action

    The Test::Valgrind::Action object (or class name) to use.

    Defaults to Test::Valgrind::Action::Test.

  • file => $file

    The file name of the script to analyse.

    Ignored if you supply your own custom command, but mandatory otherwise.

  • callers => $number

    Specify the maximum stack depth studied when valgrind encounters an error. Raising this number improves granularity.

    Ignored if you supply your own custom tool, otherwise defaults to 24 (the maximum allowed by valgrind).

  • diag => $bool

    If true, print the output of the test script as diagnostics.

    Ignored if you supply your own custom action, otherwise defaults to false.

  • regen_def_supp => $bool

    If true, forcefully regenerate the default suppression file.

    Defaults to false.

  • no_def_supp => $bool

    If true, do not use the default suppression file.

    Defaults to false.

  • allow_no_supp => $bool

    If true, force running the analysis even if the suppression files do not refer to any perl-related symbol.

    Defaults to false.

  • extra_supps => \@files

    Also use suppressions from @files besides perl's.

    Defaults to empty.


    use Test::Valgrind %options;

In the parent process, "import" calls "analyse" with the arguments it received itself - except that if no file option was supplied, it tries to pick the first caller context that looks like a script. When the analysis ends, it exits with the status returned by the action (for the default TAP-generator action, it's the number of failed tests).

In the child process, it just returns so that the calling code is actually run under valgrind, albeit two side-effects :

  • Perl::Destruct::Level is loaded and the destruction level is set to 3.

  • Autoflush on STDOUT is turned on.



When set to true, all dynamic extensions that were loaded during the analysis will be unloaded at END time by "dl_unload_file" in DynaLoader.

Since this obfuscates error stack traces, it's disabled by default.


Perl 5.8 is notorious for leaking like there's no tomorrow, so the suppressions are very likely not to be complete on it. You also have a better chance to get more accurate results if your perl is built with debugging enabled. Using the latest valgrind available will also help.

This module is not really secure. It's definitely not taint safe. That shouldn't be a problem for test files.

What your tests output to STDOUT and STDERR is eaten unless you pass the diag option, in which case it will be reprinted as diagnostics.


XML::Twig, File::HomeDir, Env::Sanctify, Perl::Destruct::Level.


All the Test::Valgrind::* API, including Test::Valgrind::Command, Test::Valgrind::Tool, Test::Valgrind::Action and Test::Valgrind::Session.

The valgrind(1) man page.


Devel::Leak, Devel::LeakTrace, Devel::LeakTrace::Fast.


Vincent Pit, <perl at>,

You can contact me by mail or on (vincent).


Please report any bugs or feature requests to bug-test-valgrind at, or through the web interface at I will be notified, and then you'll automatically be notified of progress on your bug as I make changes.


You can find documentation for this module with the perldoc command.

    perldoc Test::Valgrind


Rafaël Garcia-Suarez, for writing and instructing me about the existence of Perl::Destruct::Level (Elizabeth Mattijsen is a close second).

H.Merijn Brand, for daring to test this thing.

David Cantrell, for providing shell access to one of his smokers where the tests were failing.

The Debian-perl team, for offering all the feedback they could regarding the build issues they met.

All you people that showed interest in this module, which motivated me into completely rewriting it.


Copyright 2008,2009,2010,2011,2013,2015,2016 Vincent Pit, all rights reserved.

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.