C++ comment style: /*M ... M*/, what 'M' stands for?

Question

I have seen some 3rd party source code with comments in /*M ... M*/ style. But what 'M' stands for? (Perhaps it is used with some kind of version control, or code documentation system (like doxygen)?)

I saw it in many (if not all) source code files in opencv.

You may browse Itseez's opencv repository under GitHub by clicking here.

Oh. I forget to mention, the comment style seems to exist only in the head of the file, and it seems to declare the license.

Example:

/*M///////////////////////////////////////////////////////////////////////////////////////
//
//  IMPORTANT: READ BEFORE DOWNLOADING, COPYING, INSTALLING OR USING.
//
//  By downloading, copying, installing or using the software you agree to this license.
//  If you do not agree to this license, do not download, install,
//  copy or use the software.
//
//
//                           License Agreement
//                For Open Source Computer Vision Library

[...]
//
//M*/

Answer 1

Note: Doesn't correlate to version control and even C++

This is a problem of cross-OS EOL-problem (Win|*Nix) and visualization of not-native EOL ^M (really such string) in CRLF in pure-CR world and Linux|Mac GUIs

Example for opengl.hpp (from your sample repo): first lines

/*M///////////////////////////////////////////////////////////////////////////////////////
//

are, with proper rendering

/*
///////////////////////////////////////////////////////////////////////////////////////
//

and all glithes are results of ugly configured core.CRLF in author's Git (or ignoring it at all)