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<concept id="GUID-C6AB2B3A-BBFC-5B57-BECB-F46C96250502" xml:lang="en"><title>Cleanup

stack support for non-CBase classes</title><shortdesc>The cleanup stack supports other types of cleanup using <codeph>CleanupStack::PushL()</codeph>.</shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>

<p>The discussion of clean up so far has assumed objects to be cleaned up

are derived from <codeph>CBase</codeph>, with clean up by invoking <codeph>delete</codeph>.

Other classes need explicit cleanup support to be provided by the programmer. </p>

<p>The cleanup stack supports other types of cleanup. You can push: </p>

<ul>

<li id="GUID-7BD04FAD-E88D-5549-95DA-B62C5D07493F"><p>a pointer to any type

of object. This is an object of type <codeph>TAny*</codeph>. The cleanupstack

destroys this type of object with a call to <codeph>User::Free()</codeph> on

the pointer pushed. This is less powerful than standard cleanup, because it

frees memory and does not call the C++ destructor. </p> <p>You use the <codeph>CleanupStack::PushL(TAny*

aPtr);</codeph> overload. </p> </li>

<li id="GUID-2D143181-B8B5-5449-B29C-358CE7F8FB4A"><p>a pointer to an object

together with a specific cleanup operation for that object. The pointer and

the cleanup operation are contained in a <codeph>TCleanupItem</codeph> object. </p> <p>You

use the <codeph>CleanupStack::PushL(TCleanupItem anItem)</codeph> overload. </p> <p>You

must understand that the <codeph>TCleanupItem</codeph> object does not go

on the cleanupstack. The pointer to the object that is contained within the <codeph>TCleanupItem</codeph> object

goes on the cleanupstack. For example, if you created a TCleanupItem called

myCleanupItem, you must never call <codeph>CleanupStack::Pop(myCleanupItem);</codeph> </p> </li>

</ul>

<p>Some utility functions are provided that make construction of a suitable <codeph>TCleanupItem</codeph> easy.

See <xref href="GUID-18EF9CFA-5080-5F89-89EC-C64897612D6B.dita">How to clean up

non-CBase classes</xref>.</p>

</conbody></concept>