Emacs imenu and speedbar+semantic fails because of indentation in c++ mode

My problem is that imenu or speedbar/semantic fails because of indentation. For this simple file, it is ok:

#include <iostream>
void bar() {
   std::cout << "bar" << std::endl;
}

But if I want to put function bar in a namespace and indent its code:

with speedbar (having (require 'semantic/sb) in init.el), I don't have the file tags in the speedbar frame, and I got "File mode specification error: (void-function c-subword-mode)" in minibuffer
with M-X imenu, I got "No items suitable for an index found in this buffer" in minibuffer

Exemple code that fails:

#include <iostream>

namespace foo {
    void bar() {
    std::cout << "bar" << std::endl;
    }
}

It is not the namespace that makes it fail, but the identation. The following fails too:

#include <iostream>
    void bar() {
       std::cout << "bar" << std::endl;
    }

Any idea why and how to have it to work?

Thanks!!

EDIT: Ok the solution is indeed speedbar+sementics. It actually works (I had something wrong in my init.el...)

Solution

Maybe, the example regexp from imenu.el is used together with imenu-example--create-c-index:

(defvar imenu-example--function-name-regexp-c
  (concat
   "^[a-zA-Z0-9]+[ \t]?"        ; type specs; there can be no
   "\\([a-zA-Z0-9_*]+[ \t]+\\)?"    ; more than 3 tokens, right?
   "\\([a-zA-Z0-9_*]+[ \t]+\\)?"
   "\\([*&]+[ \t]*\\)?"         ; pointer
   "\\([a-zA-Z0-9_*]+\\)[ \t]*("    ; name
   ))

The caret ^ at the beginning means beginning of line. If you insert [[:blank:]]* behind it also function definitions with leading spaces are indexed.

I do not know whether stuff like

else if(...) {
...
}

gives false positives in this case. (You have to try.)

Actually, if I had sufficient time I would try to use semantic or ctags for the indexing. That would be much more robust.

Note, I did not try this. I just had a look at imenu.el. (Currently, I do not have much spare time. Sorry.)