SUMMARY
***
C++ Namespace Alias is not recognized by diagnostics tool, flags all mentions as errors.
***


STEPS TO REPRODUCE
1. Copy code:
#include <filesystem>
namespace fs = std::filesystem;
using namespace std;
int main(){ fs::path somepath; somepath = "./somepath" }

OBSERVED RESULT
Diagnostic tool marks namespace alias as "expected namespace name", and all following mentions of the alias as "use of undeclared identifier".

EXPECTED RESULT
The diagnostic tool recognizing the namespace alias,  and replacing it with the namespace internally for the rest fo the code.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: 
Linux Manjaro
KDE Plasma Version: 
5.27.7
KDE Frameworks Version: 
5.109.0
Qt Version: 
5.15.10

ADDITIONAL INFORMATION