The cppcheck warning below is not displayed by the warnings-ng cppcheck plugin. It seems that the lack of the <location> tag in this warning might be the issue preventing the scanner from detecting it?

<?xml version="1.0" encoding="UTF-8"?>
 <results version="2">
 <cppcheck version="1.82"/>
 <errors>
 <error id="missingInclude" severity="information" msg="Cppcheck cannot find all the include files (use --check-config for details)" verbose="Cppcheck cannot find all the include files. Cppcheck can check the code without the include files found. But the results will probably be more accurate if all the include files are found. Please check your project's include directories and add all of them as include directories for Cppcheck. To see what files Cppcheck cannot find use --check-config."/>
 </errors>
 </results>