My attempt at adding a function to help with the bubbling phase of walking the AST.

myVisitor.cpp

unsigned clang_visitChildrenWithPost(CXCursor parent,
                                     CXCursorVisitor visitor,
                                     CXPostChildrenVisitor post_visitor,
                                     CXClientData client_data) {
    clang::cxcursor::CursorVisitor CursorVis(clang_Cursor_getTranslationUnit(parent), visitor, client_data,
                          /*VisitPreprocessorLast=*/false,
                          /*VisitIncludedPreprocessingEntries=*/false,
                          /*RegionOfInterest=*/clang::SourceRange(),
                          /*VisitDeclsOnly=*/false,
                          /*PostChildrenVisitor=*/post_visitor);
    return CursorVis.VisitChildren(parent);
}

myVisitor.hpp

#ifdef __cplusplus
extern "C" {
#endif

typedef bool CXPostChildVisitResult;
bool CXPostChildVisit_Continue = false;
bool CXPostChildVisit_Break = true;

// copy of
// clang::cxcursor::CursorVisitor::PostChildrenVisitorTy
typedef CXPostChildVisitResult (*CXPostChildrenVisitor)(CXCursor cursor, CXClientData client_data);

unsigned clang_visitChildrenWithPost(CXCursor parent,
                                     CXCursorVisitor visitor,
                                     CXPostChildrenVisitor post_visitor,
                                     CXClientData client_data);

#ifdef __cplusplus
}
#endif