Just comment the line, it worked for me (cstddef file).

@JonB

Last edit my code :

DataReceiver::DataReceiver(QObject *parent) : QObject{parent} { _manager.setAutoDeleteReplies(true); } void DataReceiver::start() { _connection++; if(_connection > 1) return; _takeData = true; run(); } void DataReceiver::stop() { _takeData = false; _connection = 0; _data.clear(); } void DataReceiver::getData() { _data.clear(); QString url = QString("http://localhost:%1/sample").arg(_port); QUrl _apiUrl(url); QNetworkRequest _request(_apiUrl); _reply = _manager.get(_request); connect(_reply, &QNetworkReply::readyRead, this, &DataReceiver::onReadReady); connect(_reply, &QNetworkReply::finished, this, &DataReceiver::onFinished); } void DataReceiver::run() { if(!_takeData) return; getData(); } void DataReceiver::onReadReady() { _data += _reply->readAll(); } void DataReceiver::onFinished() { emit sendData(_data); run(); }

its working. time slow down from 65ms to 165ms but its working.

I managed to solve it by moving an #include (of the class that has the #include "ExpressionEvaluator/exprtk.hpp" in it) that was in a .cpp file to the .h file and putting it before the #include of the class that has the #include <windows.h> in it.
Thanks everyone for the help.

@Christian-Ehrlicher said in building qsqlmysql.dll for msvc error:

Forgot to copy or typo?

I forgot to copy.
I looked into Makefile.Release and realised that instead of

C:\mysql\include

this It was including this

C:\Program Files\MySQL\MySQL Server 8.0\include

I deleted qmake.stash and config.cache and repeated the qmake again and this time I generated qsqlmysql.dll successfully.
Tested it with Sample Cpp code in Qt, it's working.
@Christian-Ehrlicher Thanks for the suggestion.

@tuzepoito said in How do I use Qt headers in a CMake sub-project?:

I think I have a solution, or maybe a workaround.

Why workaround? If you want to use a library, you have to link against it what you're doing now - how should this be a workaround?

The QtWebView module comes to mind for that.

Here the bug report for this issue: https://bugreports.qt.io/browse/QTBUG-78086

Hi.

I think it just for a static QObject like QFile in Application ...
It can solve with static function to create a static object in first call...

Hi and welcome to devnet,

What version of Windows are you using ?
Can you run your application from the same command prompt ?

@JKSH Yes, I created two simple console applications and added required libraries to them. Compiler keys are identical. I checked carefully. A one project have a mistake, and another doesn't have For example, a project with subprojects have this error, but QT Widgets does not have (but not always). Heisenbug?

@JonB well, I thought it just creates a new build file for the new compiler (which it does), but I have to admit my understanding for compilers is not very deep.

在Qt Creator中，项目->Build，Build的步骤修改Target为Current executable。

@mrjj

Ok. I have fixed it temporary by defining in the .pro file:
DEFINES += _ATL_NATIVE_INITIALIZATION

And also reported it https://bugreports.qt.io/browse/QTBUG-63772 . Thank you.

@AndersDK Not sure how to handle this (I don't do much on Windows). The correct runtime package from Microsoft must be installed on users machine. I do not know whether Microsoft allows to distribute this runtime. If not your installer could maybe download it from Microsoft if it is not installed and install then.

Hi, just to want add, while Qt Creator's capturing of your qDebug() output is usually 100%, but if you want to be sure to get everything, you could try running DebugView when your app exits.

Hi,

QtWebKit has been deprecated in 5.5 and won't be released as prebuilt module starting with 5.6. You still can build it yourself from sources though.

You can find Qt 5.5.1 here

You have a list of examples here

@alex_malyu Very helpful post, thanks!