Hi. This is very similar to bug 19669. I'm running emacs from revision
6e1fac9, which has the fix to bug 19969: revision d69e9f1c.

I'm opening a file tst.hh (attached). Then "emacs -Q -nw tst.hh". Then
any interactive command (M-x, for instance). The result has
fontification issues, as shown by the attached image.