Difference between revisions of "IDE Debug Helpers"

From Qt Wiki
Jump to: navigation, search
(Convert ExpressionEngine links)
 
(15 intermediate revisions by 9 users not shown)
Line 1: Line 1:
{{Cleanup | reason=Auto-imported from ExpressionEngine.}}
 
 
 
[[Category:Tools::QtCreator]]
 
[[Category:Tools::QtCreator]]
 
[[Category:Developing_Qt]]
 
[[Category:Developing_Qt]]
 
= IDE debug helpers =
 
  
 
== Qt Creator ==
 
== Qt Creator ==
  
 
Qt Creator directly supports introspection of all Qt Containers and QObject derived classes for Qt 4 and Qt 5.
 
Qt Creator directly supports introspection of all Qt Containers and QObject derived classes for Qt 4 and Qt 5.
User defined types can be supported in addition, see [http://doc.qt.io/qtcreator-2.8/creator-debugging-helpers.html the Qt Creator documentation] for details.
+
User defined types can be supported in addition, see [http://doc.qt.io/qtcreator/creator-debugging-helpers.html the Qt Creator documentation] for details.
  
== MS visual studio QString & QByteArray expansions ==
+
== LLDB ==
  
The new layout of QString in Qt 5 is hard to inspect using the debugger.
+
There is an effort to introspect Qt types using LLDB at https://bitbucket.org/lukeworth/lldb-qt-formatters.
The following code can be added to autoexp.dat (c:files(x86)visual studio 9.0\common7\packages\debugger\autoexp.dat)
 
You should add it to the <nowiki>[Visualizer]</nowiki> section, before the STL/ATL containers.
 
  
<code>
+
KDevelop ships formatter scripts in its LLDB plugin for Qt types that can be used directly in plain LLDB. https://unlimitedcodeworks.xyz/blog/2016/08/20/gsoc-kdevelop-lldb-final-report/#using-data-formatter-scripts-outside-kdevelop
; Qt types
 
QStringData{
 
preview ([(unsigned short*)$e.d + 2 + $e.offset,su])
 
stringview ([(unsigned short*)$e.d + 2 + $e.offset,sub])
 
}
 
QString{
 
preview ([$e.d])
 
}
 
QByteArrayData{
 
preview ([(unsigned char*)$e.d + 4 + $e.offset,s])
 
stringview ([(unsigned char*)$e.d + 4 + $e.offset,sb])
 
}
 
QByteArray{
 
preview ([$e.d])
 
}
 
</code>
 
 
 
Unfortunately, sizeof() cannot be used. That is why there is a constant 2 or 4 for the offset pointer.
 
For an x64 build, the sizes most likely need to be doubled.
 
  
== MS Visual Studio 2012 ==
+
== MS Visual Studio 2012 and up ==
  
 
There is a new way to visualize native type, see
 
There is a new way to visualize native type, see
[http://code.msdn.microsoft.com/Writing-type-visualizers-2eae77a2 http://code.msdn.microsoft.com/Writing-type-visualizers-2eae77a2] for details.
+
[https://docs.microsoft.com/en-us/visualstudio/debugger/create-custom-views-of-native-objects?view=vs-2019 Create custom views of C++ objects in the debugger using the Natvis framework] and [http://blogs.msdn.com/b/vcblog/archive/2013/06/28/using-visual-studio-2013-to-write-maintainable-native-visualizations-natvis.aspx Using Visual Studio 2013 to write maintainable native visualizations (natvis)] for details.
  
Ready-made .natvis files are included in the [http://wiki.qt.io/QtVSAddin Visual Studio add-in], and can be grabbed directly from [https://qt.gitorious.org/qt-labs/vstools/source/tools/Qt4EEAddin/qt5.natvis gitorious].
+
The qt5.natvis file is also included in the [http://wiki.qt.io/QtVSAddin Visual Studio add-in] which automatically installs it in the correct directory.
  
So we can visualize QString and some other types using .natvis file
+
So we can visualize QString and some other types using [https://code.qt.io/cgit/qt-labs/vstools.git/tree/src/qtvstools/qt5.natvis.xml qt5.natvis] file
(save to file: USERPROFILEDocuments\Visual Studio 2012\Visualizers\Qt5.natvis)
+
(save to file: %USERPROFILE%\Documents\Visual Studio <version>\Visualizers\qt5.natvis, remove all occourences of '##NAMESPACE##::' - it's replaced by the a Qt namespace by the installer but the default Qt installation has no namespace)
<code>
+
<pre>
 
<?xml version="1.0" encoding="utf-8"?>
 
<?xml version="1.0" encoding="utf-8"?>
 
<AutoVisualizer >
 
<AutoVisualizer >
  
 
<Type Name="QString">
 
<Type Name="QString">
<DisplayString>{(char*)d + d->offset,su}</DisplayString>
+
    <DisplayString>{((reinterpret_cast&lt;unsigned short*&gt;(d)) + d->offset / 2),sub}</DisplayString>
</Type>
+
    <StringView>((reinterpret_cast&lt;unsigned short*&gt;(d)) + d->offset / 2),sub</StringView>
 
+
    <Expand>
<Type Name="QtPrivate::RefCount">
+
        <Item Name="[size]">d-&gt;size</Item>
<DisplayString>{atomic}</DisplayString>
+
        <Item Name="[referenced]">d-&gt;ref.atomic._q_value</Item>
</Type>
+
        <ArrayItems>
 
+
            <Size>d-&gt;size</Size>
<Type Name="QBasicAtomicInteger&amp;amp;amp;lt;int&amp;amp;amp;gt;">
+
            <ValuePointer>((reinterpret_cast&lt;unsigned short*&gt;(d)) + d->offset / 2),c</ValuePointer>
<DisplayString>{_q_value}</DisplayString>
+
        </ArrayItems>
</Type>
+
    </Expand>
 
+
</Type>
<Type Name="QTypedArrayData&amp;amp;amp;lt;'''&amp;amp;gt;">
 
<DisplayString>{{Count = {size}}}</DisplayString>
 
<Expand>
 
<Item Name="[size]">size</Item>
 
<ArrayItems>
 
<Size>size</Size>
 
<ValuePointer>(iterator) ((char''')this + offset)</ValuePointer>
 
</ArrayItems>
 
</Expand>
 
</Type>
 
  
 
<Type Name="QByteArray">
 
<Type Name="QByteArray">
<DisplayString>{*d}</DisplayString>
+
    <DisplayString>{((reinterpret_cast&lt;char*&gt;(d)) + d-&gt;offset),sb}</DisplayString>
</Type>
+
    <StringView>((reinterpret_cast&lt;char*&gt;(d)) + d-&gt;offset),sb</StringView>
 +
    <Expand>
 +
        <Item Name="[size]">d-&gt;size</Item>
 +
        <Item Name="[referenced]">d-&gt;ref.atomic._q_value</Item>
 +
        <ArrayItems>
 +
            <Size>d-&gt;size</Size>
 +
            <ValuePointer>((reinterpret_cast&lt;char*&gt;(d)) + d-&gt;offset),c</ValuePointer>
 +
        </ArrayItems>
 +
    </Expand>
 +
</Type>
  
 
<!— More Qt5 types… —>
 
<!— More Qt5 types… —>
  
 
</AutoVisualizer>
 
</AutoVisualizer>
</code>
+
</pre>
 +
 
 +
== MS Visual Studio before 2012 - QString & QByteArray expansions ==
  
== MS Visual Studio 2013 ==
+
The new layout of QString in Qt 5 is hard to inspect using the debugger.
 +
The following code can be added to autoexp.dat (c:\program files(x86)\visual studio 9.0\common7\packages\debugger\autoexp.dat)
 +
You should add it to the <nowiki>[Visualizer]</nowiki> section, before the STL/ATL containers.
  
The ".natvis" files introduced in MSVS2012 received some additional attention in MSVS2013:
+
<pre>
 +
; Qt types
 +
QStringData{
 +
preview ([(unsigned short*)$e.d + $e.offset,su])
 +
stringview ([(unsigned short*)$e.d + $e.offset,sub])
 +
}
 +
QString{
 +
preview ([$e.d])
 +
}
 +
QByteArrayData{
 +
preview ([(unsigned char*)$e.d + $e.offset,s])
 +
stringview ([(unsigned char*)$e.d + $e.offset,sb])
 +
}
 +
QByteArray{
 +
preview ([$e.d])
 +
}
 +
</pre>
  
http://blogs.msdn.com/b/vcblog/archive/2013/06/28/using-visual-studio-2013-to-write-maintainable-native-visualizations-natvis.aspx
+
If all else fails you can always just add a watcher for
 +
  (char*)str.d + str.d->offset,su
 +
in the debugger, to see the contents of str.

Latest revision as of 19:02, 28 October 2020


Qt Creator

Qt Creator directly supports introspection of all Qt Containers and QObject derived classes for Qt 4 and Qt 5. User defined types can be supported in addition, see the Qt Creator documentation for details.

LLDB

There is an effort to introspect Qt types using LLDB at https://bitbucket.org/lukeworth/lldb-qt-formatters.

KDevelop ships formatter scripts in its LLDB plugin for Qt types that can be used directly in plain LLDB. https://unlimitedcodeworks.xyz/blog/2016/08/20/gsoc-kdevelop-lldb-final-report/#using-data-formatter-scripts-outside-kdevelop

MS Visual Studio 2012 and up

There is a new way to visualize native type, see Create custom views of C++ objects in the debugger using the Natvis framework and Using Visual Studio 2013 to write maintainable native visualizations (natvis) for details.

The qt5.natvis file is also included in the Visual Studio add-in which automatically installs it in the correct directory.

So we can visualize QString and some other types using qt5.natvis file (save to file: %USERPROFILE%\Documents\Visual Studio <version>\Visualizers\qt5.natvis, remove all occourences of '##NAMESPACE##::' - it's replaced by the a Qt namespace by the installer but the default Qt installation has no namespace)

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

<Type Name="QString">
    <DisplayString>{((reinterpret_cast<unsigned short*>(d)) + d->offset / 2),sub}</DisplayString>
    <StringView>((reinterpret_cast<unsigned short*>(d)) + d->offset / 2),sub</StringView>
    <Expand>
        <Item Name="[size]">d->size</Item>
        <Item Name="[referenced]">d->ref.atomic._q_value</Item>
        <ArrayItems>
            <Size>d->size</Size>
            <ValuePointer>((reinterpret_cast<unsigned short*>(d)) + d->offset / 2),c</ValuePointer>
        </ArrayItems>
    </Expand>
</Type>

<Type Name="QByteArray">
    <DisplayString>{((reinterpret_cast<char*>(d)) + d->offset),sb}</DisplayString>
    <StringView>((reinterpret_cast<char*>(d)) + d->offset),sb</StringView>
    <Expand>
        <Item Name="[size]">d->size</Item>
        <Item Name="[referenced]">d->ref.atomic._q_value</Item>
        <ArrayItems>
            <Size>d->size</Size>
            <ValuePointer>((reinterpret_cast<char*>(d)) + d->offset),c</ValuePointer>
        </ArrayItems>
    </Expand>
</Type>

<!— More Qt5 types… —>

</AutoVisualizer>

MS Visual Studio before 2012 - QString & QByteArray expansions

The new layout of QString in Qt 5 is hard to inspect using the debugger. The following code can be added to autoexp.dat (c:\program files(x86)\visual studio 9.0\common7\packages\debugger\autoexp.dat) You should add it to the [Visualizer] section, before the STL/ATL containers.

; Qt types
QStringData{
 preview ([(unsigned short*)$e.d + $e.offset,su])
 stringview ([(unsigned short*)$e.d + $e.offset,sub])
}
QString{
 preview ([$e.d])
}
QByteArrayData{
 preview ([(unsigned char*)$e.d + $e.offset,s])
 stringview ([(unsigned char*)$e.d + $e.offset,sb])
}
QByteArray{
 preview ([$e.d])
}

If all else fails you can always just add a watcher for

  (char*)str.d + str.d->offset,su

in the debugger, to see the contents of str.