Building the following code gives
fatal error C1083: Cannot open include file: 'main.moc': No such file or directory

main.cpp

#include <QObject>

class MyObject : public QObject
{
    Q_OBJECT;

    MyObject() : QObject(nullptr) {}
};

int main()
{
    int number = 100'00;
}

#include "main.moc"

The code works fine when digit separator is not used (i.e. int number = 10000; )

Checking the generated Makefile, the reason seems main.moc is not included as a dependency for main.obj when digit separator is used.

Sample code is attached qtbug98845.zip