<?xml version="1.0" encoding="utf-8"?>

<!-- Copyright (c) 2007-2010 Nokia Corporation and/or its subsidiary(-ies) All rights reserved. -->

<!-- This component and the accompanying materials are made available under the terms of the License 

"Eclipse Public License v1.0" which accompanies this distribution, 

and is available at the URL "http://www.eclipse.org/legal/epl-v10.html". -->

<!-- Initial Contributors:

    Nokia Corporation - initial contribution.

Contributors: 

-->

<!DOCTYPE concept

  PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">

<concept id="GUID-DF1B3C55-2CFC-49C8-88A2-D10925ECAC3E" xml:lang="en"><title>Known

Issues</title><shortdesc/><prolog><metadata><keywords/></metadata></prolog><conbody>

<section id="GUID-EB71EFD6-DBEC-4C0F-B9E5-3370204AE18A"><title>ARM RVCT compiler

issues with STLport</title><p>Due to a defect in the ARM RVCT compiler versions

2.2, 3.1 and 4.0, building STLport v4 or STLport-based applications, creates

some invalid export entries in DEF files. To workaround this issue, perform

the following steps:</p><ol>

<li id="GUID-D5C91387-CF86-4D65-ACAF-05A5500DA090"><p>Use the GCCE compiler

to generate the DEF file, if it is not available.</p></li>

<li id="GUID-A0D36B39-ECEB-431A-80FD-6005542F4D7F"><p>Ignore the warnings

generated by the ARM RVCT compiler.</p><note>When you ignore the warnings,

do not freeze the invalid export entries in the DEF file using the ARM RVCT

compiler.</note></li>

</ol></section>

<section id="GUID-DDE6596E-1A67-4219-8822-45A82C39DF0B-GENID-1-6-1-10-1-1-9-1-6-1-3-2">       <title>Use

of Global Destructor</title>       <p>Symbian does not invoke destructors

of global objects upon program termination. For example, in the code below,

the destructor <codeph>~foo()</codeph> is not called upon program termination.

At the moment, it is advised not to perform any important operations using

destructors.</p><codeblock xml:space="preserve">#include 

using namespace std; 

class foo

{

public:

foo()

{

cout <<"Entering foo\n"; 

}

~foo()

{

cout <<"Leaving foo\n";

}

};

foo foo_bar; 

int main(void)

{

return 0;

}

</codeblock>     </section>

<section id="GUID-DDE6596E-1A67-4219-8822-45A82C39DF0B-GENID-1-6-1-10-1-1-9-1-6-1-3-3">       <title>Issues

with <codeph>new</codeph> operator</title>       <p>Throwing <codeph>bad_alloc</codeph> or

any object from new on ARMV5 platfrom crashes. RVCT reports an exception when <codeph>new</codeph> throws <codeph>bad_alloc</codeph>.

The problem occurs even if the user throws any object from within an overloaded

operator <codeph>new</codeph>. The following new signatures are affected:</p><codeblock xml:space="preserve">void *operator new(unsigned int aSize);

void *operator new[](unsigned int aSize);

</codeblock><p>The following code snippet is an example that depicts the problem:</p><codeblock xml:space="preserve">class Dummy

{

}; 

void *operator new(unsigned int aSize)

{

void* __y = malloc(aSize);

// try to simulate bad alloc

if (__y == 0)

{

throw Dummy(); //this will result in a crash

}

return __y;

}

</codeblock><p>To implement user owned overloaded version of new, the user

must implement them as class specific. The other way this could be achieved

is by defining new similar to:</p><codeblock xml:space="preserve">void* operator new(size_t s,newarg) throw (std::bad_alloc)</codeblock><p>and

invoking it as:</p><codeblock xml:space="preserve">Myclass* my = new(S60) Myclass()</codeblock> 

   </section>

<section id="GUID-DDE6596E-1A67-4219-8822-45A82C39DF0B-GENID-1-6-1-10-1-1-9-1-6-1-3-4">       <title>The <codeph>id</codeph> Member

Issue</title>       <p>The <codeph>id</codeph> member variable of facet classes

cannot be accessed directly, it has to be accessed via the <codeph>GetFacetLocaleId()</codeph> interface.</p><p>Following

code snippet is an example that illustrates how to <codeph>uselocale::id</codeph> while

writing an application on top of the Standard Template Library (STL). Declare

a static method <codeph>GetFacetLocaleId()</codeph> instead of the member

variable id when, defining a class <codeph>base_facet</codeph> inherited from <codeph>locale::facet</codeph> in

a header file.</p><codeblock xml:space="preserve">//b_facet.h 

class base_facet : public locale::facet 

{ 

public: 

static locale::id; 

GetFacetLocaleId(); // in place of static locale::id

id; 

};

</codeblock><p>In the source file define the method <codeph>GetFacetLocaleId()</codeph>. </p><codeblock xml:space="preserve">//b_facet.cpp

locale::id base_facet_id; 

locale::id& base_facet::GetFacetLocaleId()

{ 

return base_facet_id; 

}

</codeblock>     </section>

<section id="GUID-0EBB7F0F-2C2D-4707-BD53-96DC40443CAF"><title>Interleaving

Symbian and Standard C++ Code</title><p>The user must exercise caution while

using <codeph>try</codeph> or <codeph>catch</codeph>, and <codeph>trap</codeph> while

interleaving Symbian C++ and Standard C++ code. Adapter code is required to

handover or suppress exception coming from the Standard C++ to Symbian C++

code.</p><p>Following code snippet illustrates how to use the adaptor code.

Adaptor code can be a part of DLLA.  </p><p><b>DLL A - Symbian C++ code</b></p><codeblock xml:space="preserve">void CDoIt::Doit()

{

   class foo *p = new __foo__();

   p->bar();

   delete p;

};

</codeblock><p><b>DLLB - Standard C++ code</b></p><codeblock xml:space="preserve">class foo {

public:

  foo(); //constructor

  bar(); // throw exception

};

</codeblock><p><b>DLLC - Adaptor code</b></p><codeblock xml:space="preserve">class __foo__ {

  foo *p;

public:

  __foo__();

  bar();

};

void __foo__::__foo__()

{

   int err = 0;

   try {

      p = new foo();

   } catch {

     err = some error

   }

   User::LeaveIfError(err);

};

void __foo__::bar()

{

   int err = 0;

   try {

      p->bar();

   } catch {

     err = some error

   }

   User::LeaveIfError(err);

};

</codeblock></section>

</conbody></concept>