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1<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"2 "http://www.w3.org/TR/html4/strict.dtd">3<html>4<head>5 <title>Implicit Checks</title>6 <link type="text/css" rel="stylesheet" href="menu.css">7 <link type="text/css" rel="stylesheet" href="content.css">8 <script type="text/javascript" src="scripts/menu.js"></script>9 <script type="text/javascript" src="scripts/expandcollapse.js"></script>10 <style type="text/css">11 tr:first-child { width:20%; }12 </style>13</head>14<body onload="initExpandCollapse()">15 16<div id="page">17<!--#include virtual="menu.html.incl"-->18 19<div id="content">20<h1>Implicit Checkers</h1>21Even though the implicit checkers do not produce any warnings, they are used to22support the analyzer core and model known APIs. See also23<a href = "available_checks.html">Default Checkers</a>24and <a href = "alpha_checks.html">Experimental (Alpha) Checkers</a>.25<ul>26<li><a href="#core_implicit_checkers">Core Implicit Checkers</a></li>27<li><a href="#osx_implicit_checkers">OS X Implicit Checkers</a></li>28</ul>29 30<!-- =========================== core implicit =========================== -->31<h3 id="core_implicit_checkers">Core Implicit Checkers</h3>32<table class="checkers">33<colgroup><col class="namedescr"><col class="example"></colgroup>34<thead><tr><td>Name, Description</td><td>Example</td></tr></thead>35 36<tbody>37<tr><td><div class="namedescr expandable"><span class="name">38core.DynamicTypePropagation</span><span class="lang">39(C++, ObjC)</span><div class="descr">40Generate dynamic type information.</div></div></td>41<td><div class="exampleContainer expandable">42<div class="example"><pre>43// C++44class A {45public:46 A(int x) {}47 virtual int foo();48};49 50class B: public A {51public:52 B()53 :A(foo())54 // DynamicTypeInfo for 'this' rigion will wrap type 'A'55 // unless the base constructor call expression is processed56 {}57 virtual int foo();58};59</pre></div><div class="separator"></div>60<div class="example"><pre>61// Objective-C62@interface MyClass : NSObject {}63@end64 65@implementation MyClass66+ (void)foo {67 MyClass *x = [[self alloc] init];68 // DynamicTypeInfo from a cast: from 'id' to 'MyClass *'69}70@end71 72void test() {73 MyClass *x = [MyClass alloc];74 // DynamicTypeInfo from a call to alloc:75 // from 'id' to 'MyClass *'76}77</pre></div></div></td></tr>78 79 80<tr><td><div class="namedescr expandable"><span class="name">81core.builtin.BuiltinFunctions</span><span class="lang">82(C)</span><div class="descr">83Evaluate compiler builtin functions (e.g., <code>alloca()</code>)</div></div></td>84<td><div class="exampleContainer expandable">85<div class="example"><pre>86void test(int x) {87 int *p = (int *)__builtin_alloca(8);88 // evaluates to AllocaRegion89 90 if(__builtin_expect(x > 10, 0)) // evaluates to 'x > 10'91 x = 0;92}93</pre></div></div></td></tr>94 95 96<tr><td><div class="namedescr expandable"><span class="name">97core.builtin.NoReturnFunctions</span><span class="lang">98(C, ObjC)</span><div class="descr">99Evaluate "panic" functions that are known to not return to the caller.</div></div></td>100<td><div class="exampleContainer expandable">101<div class="example"><pre>102// C103void test() {104 panic(); // generate sink105}106</pre></div><div class="separator"></div>107<div class="example"><pre>108// Objective-C109@interface MyObj : NSObject {}110- (void)foo;111@end112 113@implementation MyObj114- (void)foo {115 [[NSAssertionHandler currentHandler] handleFailureInMethod:_cmd116 object:self117 file:(@"somefile.m")118 lineNumber:1119 description:(@"some text")];120 // generate sink121}122@end123</pre></div></div></td></tr>124 125</tbody></table>126 127<!-- =========================== OS X implicit =========================== -->128<h3 id="osx_implicit_checkers">OS X Implicit Checkers</h3>129<table class="checkers">130<colgroup><col class="namedescr"><col class="example"></colgroup>131<thead><tr><td>Name, Description</td><td>Example</td></tr></thead>132 133<tbody>134<tr><td><div class="namedescr expandable"><span class="name">135osx.cocoa.Loops</span><span class="lang">136(ObjC)</span><div class="descr">137Improved modeling of loops using Cocoa collection types.</div></div></td>138<td><div class="exampleContainer expandable">139<div class="example"><pre>140void test() {141 id x;142 for (x in [NSArray testObject]) {143 // assume the value of 'x' is non-nil144 }145}146</pre></div></div></td></tr>147 148 149<tr><td><div class="namedescr expandable"><span class="name">150osx.cocoa.NonNilReturnValue</span><span class="lang">151(ObjC)</span><div class="descr">152Model the APIs that are guaranteed to return a non-nil value.</div></div></td>153<td><div class="exampleContainer expandable">154<div class="example"><pre>155void test(NSArray *A) {156 id subscriptObj = A[1]; // assume the value is non-nil157}158</pre></div></div></td></tr>159 160</tbody></table>161 162</div> <!-- page -->163</div> <!-- content -->164</body>165</html>166