Gitiles
Code Review Sign In
gerrit-public.fairphone.software / platform / external / clang / 7a31d7b9e46db6c067567231923574b96c012462 / . / docs / AddressSanitizer.html
blob: aa07ae8a493cb181f82c3e92ad297c576bbb57b8 [file] [log] [blame]
Kostya Serebryanyce98c9b2011-11-28 20:51:02 +0000[diff] [blame]1<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
2 "http://www.w3.org/TR/html4/strict.dtd">
3<!-- Material used from: HTML 4.01 specs: http://www.w3.org/TR/html401/ -->
4<html>
5<head>
6 <META http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
7 <title>AddressSanitizer, a fast memory error detector</title>
8 <link type="text/css" rel="stylesheet" href="../menu.css">
9 <link type="text/css" rel="stylesheet" href="../content.css">
10 <style type="text/css">
11 td {
12 vertical-align: top;
13 }
14 </style>
15</head>
16<body>
17
18<!--#include virtual="../menu.html.incl"-->
19
Kostya Serebryany7a31d7b2011-11-28 22:34:10 +0000[diff] [blame^]20<div id="content">
21
Kostya Serebryanyce98c9b2011-11-28 20:51:02 +0000[diff] [blame]22<h1>AddressSanitizer</h1>
23<ul>
24 <li> <a href="intro">Introduction</a>
25 <li> <a href="usage">Usage</a>
26 <ul><li> <a href="has_feature">__has_feature(address_sanitizer)</a></ul>
27 <li> <a href="platforms">Supported Platforms</a>
28 <li> <a href="limitations">Limitations</a>
29 <li> <a href="status">Current Status</a>
30</ul>
31
32<h2 id="intro">Introduction</h2>
33AddressSanitizer is a fast memory error detector.
34It consists of a compiler instrumentation module and a run-time library.
35The tool can detect the following types of bugs:
36<ul> <li> Out-of-bounds accesses to <ul><li>heap <li>stack <li>globals</ul>
37 <li> Use-after-free
38 <li> Use-after-return (to some extent)
39 <li> Double-free
40</ul>
41Typical slowdown introduced by AddressSanitizer is <b>2x</b>.
42
43<h2 id="intro">Usage</h2>
44In order to use AddressSanitizer simply compile and link your program with
45<tt>-faddress-sanitizer</tt> flag and optimization level <tt>-O1</tt> or higher
46and then run it. If a bug is detected, the program will print an error message
47and exit.
48
49<h3 id="has_feature">__has_feature(address_sanitizer)</h3>
50In some cases one may need to execute different code depending on whether
51AddressSanitizer is enabled.
52<a href="LanguageExtensions.html#__has_feature_extension">__has_feature</a>
53can be used for this purpose.
54<pre>
55#if defined(__has_feature) && __has_feature(address_sanitizer)
56 code that runs only under AddressSanitizer
57#else
58 code that does not run under AddressSanitizer
59#endif
60</pre>
61
62<h2 id="platforms">Supported Platforms</h2>
63AddressSanitizer is supported on the following platforms:
64<ul> <li>Linux <ul> <li> i386 <li> x86_64 <li> ARM </ul>
65 <li>Darwin <ul> <li> i386 <li> x86_64 </ul>
66</ul>
67
68<h2 id="limitations">Limitations</h2>
69<ul>
70 <li> AddressSanitizer uses more real memory than a native run.
71 How much -- depends on the allocations sizes. The smaller the
72 allocations you make the bigger the overhead.
73 <li> On 64-bit platforms AddressSanitizer maps (but not reserves)
74 16+ Terabytes of virtual address space.
75 This means that tools like <tt>ulimit</tt> may not work as usually expected.
76 <li> Static linking is not supported.
77</ul>
78
79
80<h2 id="status">Current Status</h2>
81AddressSanitizer is work-in-progress and is not yet fully functional in the LLVM/Clang head.
82For the up-to-date usable version and full documentation refer to
83<a href="http://code.google.com/p/address-sanitizer/">http://code.google.com/p/address-sanitizer</a>.
84
85
Kostya Serebryany7a31d7b2011-11-28 22:34:10 +0000[diff] [blame^]86</div>
Kostya Serebryanyce98c9b2011-11-28 20:51:02 +0000[diff] [blame]87</body>
88</html>