<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
"http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
<title>Implicit Checks</title>
<link type="text/css" rel="stylesheet" href="menu.css">
<link type="text/css" rel="stylesheet" href="content.css">
<script type="text/javascript" src="scripts/menu.js"></script>
<script type="text/javascript" src="scripts/expandcollapse.js"></script>
<style type="text/css">
tr:first-child { width:20%; }
</style>
</head>
<body onload="initExpandCollapse()">
<div id="page">
<!--#include virtual="menu.html.incl"-->
<div id="content">
<h1>Implicit Checkers</h1>
Even though the implicit checkers do not produce any warnings, they are used to
support the analyzer core and model known APIs. See also
<a href = "available_checks.html">Default Checkers</a>
and <a href = "alpha_checks.html">Experimental (Alpha) Checkers</a>.
<ul>
<li><a href="#core_implicit_checkers">Core Implicit Checkers</a></li>
<li><a href="#osx_implicit_checkers">OS X Implicit Checkers</a></li>
</ul>
<!------------------------------- core implicit ------------------------------->
<h3 id="core_implicit_checkers">Core Implicit Checkers</h3>
<table class="checkers">
<colgroup><col class="namedescr"><col class="example"></colgroup>
<thead><tr><td>Name, Description</td><td>Example</td></tr></thead>
<tbody>
<tr><td><div class="namedescr expandable"><span class="name">
core.DynamicTypePropagation</span><span class="lang">
(C++, ObjC)</span><div class="descr">
Generate dynamic type information.</div></div></td>
<td><div class="exampleContainer expandable">
<div class="example"><pre>
// C++
class A {
public:
A(int x) {}
virtual int foo();
};
class B: public A {
public:
B()
:A(foo())
// DynamicTypeInfo for 'this' rigion will wrap type 'A'
// unless the base constructor call expression is processed
{}
virtual int foo();
};
</pre></div><div class="separator"></div>
<div class="example"><pre>
// Objective-C
@interface MyClass : NSObject {}
@end
@implementation MyClass
+ (void)foo {
MyClass *x = [[self alloc] init];
// DynamicTypeInfo from a cast: from 'id' to 'MyClass *'
}
@end
void test() {
MyClass *x = [MyClass alloc];
// DynamicTypeInfo from a call to alloc:
// from 'id' to 'MyClass *'
}
</pre></div></div></td></tr>
<tr><td><div class="namedescr expandable"><span class="name">
core.builtin.BuiltinFunctions</span><span class="lang">
(C)</span><div class="descr">
Evaluate compiler builtin functions (e.g., <code>alloca()</code>)</div></div></td>
<td><div class="exampleContainer expandable">
<div class="example"><pre>
void test(int x) {
int *p = (int *)__builtin_alloca(8);
// evaluates to AllocaRegion
if(__builtin_expect(x > 10, 0)) // evaluates to 'x > 10'
x = 0;
}
</pre></div></div></td></tr>
<tr><td><div class="namedescr expandable"><span class="name">
core.builtin.NoReturnFunctions</span><span class="lang">
(C, ObjC)</span><div class="descr">
Evaluate "panic" functions that are known to not return to the caller.</div></div></td>
<td><div class="exampleContainer expandable">
<div class="example"><pre>
// C
void test() {
panic(); // generate sink
}
</pre></div><div class="separator"></div>
<div class="example"><pre>
// Objective-C
@interface MyObj : NSObject {}
- (void)foo;
@end
@implementation MyObj
- (void)foo {
[[NSAssertionHandler currentHandler] handleFailureInMethod:_cmd
object:self
file:(@"somefile.m")
lineNumber:1
description:(@"some text")];
// generate sink
}
@end
</pre></div></div></td></tr>
</tbody></table>
<!---------------------------- OS X implicit ---------------------------------->
<h3 id="osx_implicit_checkers">OS X Implicit Checkers</h3>
<table class="checkers">
<colgroup><col class="namedescr"><col class="example"></colgroup>
<thead><tr><td>Name, Description</td><td>Example</td></tr></thead>
<tbody>
<tr><td><div class="namedescr expandable"><span class="name">
osx.cocoa.Loops</span><span class="lang">
(ObjC)</span><div class="descr">
Improved modeling of loops using Cocoa collection types.</div></div></td>
<td><div class="exampleContainer expandable">
<div class="example"><pre>
void test() {
id x;
for (x in [NSArray testObject]) {
// assume the value of 'x' is non-nil
}
}
</pre></div></div></td></tr>
<tr><td><div class="namedescr expandable"><span class="name">
osx.cocoa.NonNilReturnValue</span><span class="lang">
(ObjC)</span><div class="descr">
Model the APIs that are guaranteed to return a non-nil value.</div></div></td>
<td><div class="exampleContainer expandable">
<div class="example"><pre>
void test(NSArray *A) {
id subscriptObj = A[1]; // assume the value is non-nil
}
</pre></div></div></td></tr>
</tbody></table>
</div> <!-- page -->
</div> <!-- content -->
</body>
</html>