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<a name="atomic.porting"></a><a class="link" href="porting.html" title="Porting">Porting</a>
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<div class="toc"><dl class="toc">
<dt><span class="section"><a href="porting.html#atomic.porting.unit_tests">Unit tests</a></span></dt>
<dt><span class="section"><a href="porting.html#atomic.porting.tested_compilers">Tested compilers</a></span></dt>
<dt><span class="section"><a href="porting.html#atomic.porting.acknowledgements">Acknowledgements</a></span></dt>
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<div class="titlepage"><div><div><h3 class="title">
<a name="atomic.porting.unit_tests"></a><a class="link" href="porting.html#atomic.porting.unit_tests" title="Unit tests">Unit tests</a>
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<p>
<span class="bold"><strong>Boost.Atomic</strong></span> provides a unit test suite
to verify that the implementation behaves as expected:
</p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<span class="bold"><strong>atomic_api.cpp</strong></span> and <span class="bold"><strong>atomic_ref_api.cpp</strong></span>
verifies that all atomic operations have correct value semantics (e.g.
"fetch_add" really adds the desired value, returning the previous).
The latter tests <code class="computeroutput"><span class="identifier">atomic_ref</span></code>
rather than <code class="computeroutput"><span class="identifier">atomic</span></code> and
<code class="computeroutput"><span class="identifier">atomic_flag</span></code>. It is a
rough "smoke-test" to help weed out the most obvious mistakes
(for example width overflow, signed/unsigned extension, ...). These tests
are also run with <code class="computeroutput"><span class="identifier">BOOST_ATOMIC_FORCE_FALLBACK</span></code>
macro defined to test the lock pool based implementation.
</li>
<li class="listitem">
<span class="bold"><strong>lockfree.cpp</strong></span> verifies that the <span class="bold"><strong>BOOST_ATOMIC_*_LOCKFREE</strong></span> macros are set properly
according to the expectations for a given platform, and that they match
up with the <span class="bold"><strong>is_always_lock_free</strong></span> and
<span class="bold"><strong>is_lock_free</strong></span> members of the <span class="bold"><strong>atomic</strong></span> object instances.
</li>
<li class="listitem">
<span class="bold"><strong>atomicity.cpp</strong></span> and <span class="bold"><strong>atomicity_ref.cpp</strong></span>
lets two threads race against each other modifying a shared variable,
verifying that the operations behave atomic as appropriate. By nature,
this test is necessarily stochastic, and the test self-calibrates to
yield 99% confidence that a positive result indicates absence of an error.
This test is very useful on uni-processor systems with preemption already.
</li>
<li class="listitem">
<span class="bold"><strong>ordering.cpp</strong></span> and <span class="bold"><strong>ordering_ref.cpp</strong></span>
lets two threads race against each other accessing multiple shared variables,
verifying that the operations exhibit the expected ordering behavior.
By nature, this test is necessarily stochastic, and the test attempts
to self-calibrate to yield 99% confidence that a positive result indicates
absence of an error. This only works on true multi-processor (or multi-core)
systems. It does not yield any result on uni-processor systems or emulators
(due to there being no observable reordering even the order=relaxed case)
and will report that fact.
</li>
<li class="listitem">
<span class="bold"><strong>wait_api.cpp</strong></span> and <span class="bold"><strong>wait_ref_api.cpp</strong></span>
are used to verify waiting and notifying operations behavior. Due to
the possibility of spurious wakeups, these tests may fail if a waiting
operation returns early a number of times. The test retries for a few
times in this case, but a failure is still possible.
</li>
<li class="listitem">
<span class="bold"><strong>wait_fuzz.cpp</strong></span> is a fuzzing test for
waiting and notifying operations, that creates a number of threads that
block on the same atomic object and then wake up one or all of them for
a number of times. This test is intended as a smoke test in case if the
implementation has long-term instabilities or races (primarily, in the
lock pool implementation).
</li>
<li class="listitem">
<span class="bold"><strong>ipc_atomic_api.cpp</strong></span>, <span class="bold"><strong>ipc_atomic_ref_api.cpp</strong></span>,
<span class="bold"><strong>ipc_wait_api.cpp</strong></span> and <span class="bold"><strong>ipc_wait_ref_api.cpp</strong></span>
are similar to the tests without the <span class="bold"><strong>ipc_</strong></span>
prefix, but test IPC atomic types.
</li>
</ul></div>
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<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="atomic.porting.tested_compilers"></a><a class="link" href="porting.html#atomic.porting.tested_compilers" title="Tested compilers">Tested compilers</a>
</h3></div></div></div>
<p>
<span class="bold"><strong>Boost.Atomic</strong></span> has been tested on and is known
to work on the following compilers/platforms:
</p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
gcc 4.4 and newer: i386, x86_64, ppc32, ppc64, sparcv9, armv6, alpha
</li>
<li class="listitem">
clang 3.5 and newer: i386, x86_64
</li>
<li class="listitem">
Visual Studio Express 2008 and newer on Windows XP and later: x86, x64,
ARM
</li>
</ul></div>
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<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="atomic.porting.acknowledgements"></a><a class="link" href="porting.html#atomic.porting.acknowledgements" title="Acknowledgements">Acknowledgements</a>
</h3></div></div></div>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
Adam Wulkiewicz created the logo used on the <a href="https://github.com/boostorg/atomic" target="_top">GitHub
project page</a>. The logo was taken from his <a href="https://github.com/awulkiew/boost-logos" target="_top">collection</a>
of Boost logos.
</li></ul></div>
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<td align="right"><div class="copyright-footer">Copyright © 2011 Helge Bahmann<br>Copyright © 2012 Tim Blechmann<br>Copyright © 2013, 2017, 2018, 2020 Andrey
Semashev<p>
Distributed under the Boost Software License, Version 1.0. (See accompanying
file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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