"Professional CMake" book suggest the following:
"Targets should build successfully with or without compiler support for precompiled headers. It
should be considered an optimization, not a requirement. In particular, do not explicitly include a
precompile header (e.g. stdafx.h) in the source code, let CMake force-include an automatically
generated precompile header on the compiler command line instead. This is more portable across
the major compilers and is likely to be easier to maintain. It will also avoid warnings being
generated from certain code checking tools like iwyu (include what you use)."
Therefore, removed the "#include <PreCompiled.h>" from sources, also
there is no need for the "#ifdef _PreComp_" anymore
Convenience helpers function Tools::toStdString and Tools::fromStdString
were implemented for Qt4 or older to perform utf8 aware conversion as
QString::toStdString/QString::fromStdString were using toAscii/fromAscii
internally (see https://dreamswork.github.io/qt4/classQString.html).
Since Qt5 QString uses toUtf8/fromUTf8, which makes the helper functions
obsolete (see https://doc.qt.io/qt-5/qstring.html#fromStdString).
* in QtConcurrent::run the order of 1st and 2nd argument are swapped
* QtConcurrent::run asserts that the argument of the passed function pointer is not non-const
* Used methods of QFontDatabase are static in Qt5 and Qt6
* QTextStream::setCodec() has been removed in Qt6
* Argument of enterEvent() has changed from QEvent to QEnterEvent
* QTextCharFormat::setFamily() is deprecated
* Using copy-ctor but class TechDraw::anglePoints has a trivial copy-ctor but non trivial assign operator [-Wclazy-rule-of-two-soft]
* Using copy-ctor but class TechDraw::arcPoints has a trivial copy-ctor but non trivial assign operator [-Wclazy-rule-of-two-soft]
* Missing reference in range-for with non trivial type [-Wclazy-range-loop-reference]
* C++11 range-loop might detach Qt container (QList) [-Wclazy-range-loop-detach]
* signal arguments need to be fully-qualified (TechDrawGui::QGIView instead of QGIView) [-Wclazy-fully-qualified-moc-types]
* Use multi-arg instead [-Wclazy-qstring-arg]
* Use midRef() instead [-Wclazy-qstring-ref]
Add the optional Qt::MSWindowsFixedSizeDialogHint parameter to all uses of the QInputDialog::getX static functions to silence a Qt/Windows debug mode warning about QWindowsWindow::setGeometry: Unable to set geometry. Increase the size of the unit calculator to eliminate the same warning. Finally, call adjustSize() on the "Unsaved Changes" dialog to silence the warning.