Hello,

In the case of C++ partial template specialization [1], functions are
shown as variables.  Please look at the attached screenshots.

  1. emacs -Q
  2. open attached C++ code "specialization.cc"

  attachments:
  - NG_cc-partial-specialization.png
  - OK_cc-partial-specialization.png
  - specialization.cc

In cc-engine.el c-do-declarators, given CDD-NOT-TOP is non-nil at blow:

-------------------------------------------------------------
(defun c-do-declarators
    (cdd-limit cdd-list cdd-not-top cdd-comma-prop cdd-function)

[..snip..]

    (while
	(and (not cdd-exhausted)
	     (setq cdd-decl-res (c-forward-declarator cdd-limit)))
      (setq cdd-next-pos (point)
	    cdd-id-start (car cdd-decl-res)
	    cdd-id-end (cadr cdd-decl-res)
	    cdd-got-func (and (eq (char-after) ?\()
			  (or (not (c-major-mode-is 'c++-mode))
			      (not cdd-not-top)  <<<< nil if "class foo<T, ..>"
			      (car (cddr (cddr cdd-decl-res))) ; Id is in
					; parens, etc.
			      (save-excursion
				(forward-char)
				(c-forward-syntactic-ws)
				(looking-at "[*&]")))
-------------------------------------------------------------

-------------------------------------------------------------
template<>>
class One<char> {
public:
    One() {}    // (not cdd-not-top): t
private:
    char _c;
};

template<typename T>
class Two<T, char> {    // "," in "class A<...>"
public:
    Two() {}    // (not cdd-not-top): nil
private:
    T _t;
    char _c;
};
-------------------------------------------------------------

After a brief investigation, the attached cc-engine.el patch seems to
solve this issue at least, but it is not tested enough.

  attachments:
  - 0001-cc-mode-Fix-function-fontification-in-the-case-of-C-.patch


[1] https://en.cppreference.com/w/cpp/language/partial_specialization
-------------------------------------------------------------
$ g++ -o specialization specialization.cc
$ ./specialization
One<T>: primary
One<char>: specialization
Two<T1, T2>: primary
Two<T, char>: specialization
Two<T, T*>: specialization
Two<T, T&>: specialization
Two<T, T[]>: specialization
Two<char, char*>: specialization
Two<char, char&>: specialization
Two<char, char[]>: specialization
$
-------------------------------------------------------------

Regards,
  Naofumi