Databases
StackOverflow2013
Postsdbo
POpimpl idiom struct memory leak
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POpimpl idiom struct memory leak
    primarykey
    data
    text
    <p>We are using the pimpl idiom in our classes. The pimpl struct is declared in the class which contains the pimpl pointer like so:</p> <pre><code>struct MyClassImpl; friend struct MyClassImpl; boost::scoped_ptr&lt;MyClassImpl&gt; m_Impl; </code></pre> <p>The implementation for the pimpl is in a seperate file called MyClassImpl.cpp For example:</p> <pre><code> struct MyClass::MyClassImpl { QString m_Name; int m_Type; double m_Frequency; int m_DefaultSize; QVariant m_DefaultValue; boost::shared_ptr&lt;SomeOtherClass&gt; m_SomeOtherClass; ~MyClassImpl() { } }; </code></pre> <p>In the constructor of a class that contains a pimpl pointer, I would have in the member variable initialization list something like</p> <pre><code>m_Impl(new MyClassImpl()) </code></pre> <p>Now, we have enabled memory leak detection in our source code like so:</p> <pre><code>// Memory leaks detection in Visual Studio #if defined (_WIN32) &amp;&amp; defined (_DEBUG) # define _CRTDBG_MAP_ALLOC # include &lt;crtdbg.h&gt; # define new new(_NORMAL_BLOCK ,__FILE__, __LINE__) #endif </code></pre> <p>I am finding that when the program exits, memory leaks are reported for the MyClassImpl() struct m_Impl(new MyClassImpl()):</p> <pre><code>..\..\src\MyClass.cpp(29) : {290222} normal block at 0x0B9664E0, 48 bytes long. Data: &lt;X l V Y@&gt; 58 1C 6C 03 56 00 00 00 00 00 00 00 00 00 59 40 </code></pre> <p>I don't understand why since the m_Impl is a boost::scoped_ptr and the QString, QVariant, and shared_ptr are all managed. Any ideas?</p>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. USMarc Mutz - mmutz
    1. USBizmarck
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    2. PO
      singulars
      1. PTAnswer
    1. VO
      singulars
      1. POpimpl idiom struct memory leak
      1. This table or related slice is empty.
      1. VTUpMod
    1. COAre you sure the MyClass destructor is invoked prior to invoking exit?
      singulars
      1. POpimpl idiom struct memory leak
      1. USSam Miller
    2. COGet Visual Leak Detector if you want to get better info on the leak.
      singulars
      1. POpimpl idiom struct memory leak
      1. US0xbaadf00d
    3. COThe shared_ptr might be part of a cycle of references and prevent stuff from being freed. It's impossible to tell without the definition of `SomeOtherClass` tho.
      singulars
      1. POpimpl idiom struct memory leak
      1. USltjax
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload