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<h2 id="asan">Address Sanitizer</h2>

<p>Android platform developers use <a href="/devices/tech/debug/asan.html">AddressSanitizer</a>
(ASan) to find memory bugs in C/C++.</p>

</p>Since Android 8.0 (Oreo) it's also possible to use ASan to debug apps on non-rooted production
devices. You can find instructions on the
<a href="https://github.com/google/sanitizers/wiki/AddressSanitizerOnAndroidO">ASan wiki</a>.</p>

<h2 id="malloc_debug">Malloc debug</h2>

<p>See <a
href="https://android.googlesource.com/platform/bionic/+/master/libc/malloc_debug/README.md">Malloc
Debug</a> and <a
href="https://android.googlesource.com/platform/bionic/+/master/libc/malloc_debug/README_api.md">Native
Memory Tracking using libc Callbacks</a> for a thorough description of the
debugging options available for native memory issues.</p>

<h2 id="malloc-stats">Malloc statistics</h2>

<p>
  Android supports the <a href="http://man7.org/linux/man-pages/man3/mallinfo.3.html"
  ><code>mallinfo(3)</code></a>and <a href="http://man7.org/linux/man-pages/man3/malloc_info.3.html"
  ><code>malloc_info(3)</code></a> extensions to <code>&lt;malloc.h&gt;</code></a>.
  The <code>malloc_info</code> function is available in Android 6.0 and later and
  its XML schema is documented in Bionic's
  <a href="https://android.googlesource.com/platform/bionic/+/master/libc/include/malloc.h"
  ><code>&lt;malloc.h&gt;</code></a>.
</p>

<h2 id="ddms">Dalvik Debug Monitor Server</h2>

<p>You can also use the <a
href="https://developer.android.com/studio/profile/ddms.html">Dalvik Debug
Monitor Server</a> (DDMS) to obtain a graphical view of Malloc Debug
output.</p>

<p>To use DDMS, first turn on its native memory UI:</p>
<ol>
<li>Open <code>~/.android/ddms.cfg</code></li>
<li>Add the line: <code>native=true</code></li>
</ol>

<p>Upon relaunching DDMS and selecting a process, you can switch to the new
native allocation tab and populate it with a list of allocations. This is
especially useful for debugging memory leaks.</p>

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