This is makedepend that comes with XFree86 distribution with several changes
(enumerated below). Here is the copyright notice (from the source files):

   Copyright (c) 1993, 1994  X Consortium

   Permission is hereby granted, free of charge, to any person obtaining a copy
   of this software and associated documentation files (the "Software"), to deal
   in the Software without restriction, including without limitation the rights
   to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   copies of the Software, and to permit persons to whom the Software is
   furnished to do so, subject to the following conditions:

   The above copyright notice and this permission notice shall be included in
   all copies or substantial portions of the Software.

   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
   X CONSORTIUM BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
   AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
   CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

   Except as contained in this notice, the name of the X Consortium shall not be
   used in advertising or otherwise to promote the sale, use or other dealings
   in this Software without prior written authorization from the X Consortium.

   Author: Todd Brunhoff, Tektronix, Inc. and MIT Project Athena

The following changes have been made to it:

-*- Renamed "makedepend" into "makedep" to conform with pity DOS file naming
    convention (8 + 3).

-*- Converted to C++ (better syntax checking and so on ...). Replaced
    "boolean" with "bool", "TRUE" -> "true" and "FALSE" -> "false".

-*- Re-indented to Crystal Space indention style.

-*- When run with no files on command line, display a short message and exit.

-*- Added the "-h" option for a short command-line help.

-*- Added the "-S" option so that "makedep" will generate dependencies
    on system include files (like before and like gcc -M). By default
    (i.e. without "-S" switch) it lists only user include files (i.e.
    those that are #include'd "...", system include files are considered
    those that are #include'd <...> this way).

-*- Modified so that by default it won't create backups of makefile. If you
    need them, run makedep with "-b" switch.

-*- Added the "-c" switch to tell "makedep" to create makefile if it does
    not exist.

-*- Added the "-r" switch to remove directory prefix from object files.

-*- Added preprocessor predefines required on Win32 platform.

-*- Added displaying of include file history on errors and warnings.
    Example:

makedep: warning:  ./include/def.h: 23: #error "You are not allowed to include this file! Use sysdef.h instead."
makedep: warning:  included from ./include/csutil/impexp.h
makedep: warning:  included from ./include/csparser/crossbld.h
makedep: warning:  included from libs/csparser/crossbld.cpp

-*- Updated man page on all above improvements.

-*- Added a version number to distinguish between different versions of makedep.
    Although makedepend itself is pretty old, I've started from version 0.0.1
    as I don't have any idea what the version number should be :-)
    Added the "-V" switch to display the version.
