/usr/include not in code-model built-in header paths

Clang-code-model issue presumed.

Hello, I want to debug digging in qt sources for the pgmodeler app.
I installed qt 5.9.7 on ubuntu xenial from the installer and with pre-compiled qt first.
Code model works fine there.

I then compiled debug-qt locally with gcc, registering qt version and the new kit.
With this latter custom kit, /usr/include is not in built-in headers anymore : the parser complains about missing (/usr/include/)features.h . Compilation is fine though.

If it is not a bug in gcctoolchain::gccHeaderPaths(), then what can this problem be related to?

On top of what I mentioned there https://forum.qt.io/topic/98704/custom-kit-self-compiled-qt-5-9-features-h-not-found ;

I did try to set CMAKE SYSROOT as suggested here QTCREATORBUG-16155 and there https://forum.qt.io/topic/95523/qt-creator-clang-code-model-doesn-t-find-types-even-though-code-compiles/8.

Attached CMake settings from qtcreator and the code model widget.

Best regards, Maxime

Edit : SOLVED, see https://forum.qt.io/topic/98704/custom-kit-self-compiled-qt-5-9-features-h-not-found