The head guard of glad/gl.h won't work as it should when header only is selected in glad2 generator
Problems arise when multiple sources refer to header files in a specific order.
<img width="241" alt="s" src="https://github.com/Dav1dde/glad/assets/12566988/269879ce-2205-4dce-b9e1-f9584ab3ae1b">
