In this file I am going to describe what I did to try build BRL-CAD

1.Downloaded 32 bit version of Cygwin from https://www.cygwin.com/
2.Installed Cygwin with "gcc", "g++", "gdb" and "make" packages
3.Downloaded Win32 Installer for cmake version 3.1.0-rc3 and installed it.
4.Downloaded Subversion-1.8.10 from http://www.sourceforge.net/projects/win32svn/ and installed it.
5.Added cygwin\bin and \Subversion\bin to the PATH
5.Downloaded BRL-CAD source code via subversion by running "svn checkout svn://svn.code.sf.net/p/brlcad/code/brlcad/trunk brlcad-svn-trunk" in command promt
6.Set up a build directory by running the following commands in cmd:

D:
cd brlcad-svn-trunk
mkdir .build
cd .build
cmake .. -DBRLCAD_ENABLE_STRICT=NO -DBRLCAD_BUNDLED_LIBS=ON -DCMAKE_BUILD_TYPE=Release

7.The build is unsuccessful and the following is the build log:

CMake Warning at CMakeLists.txt:139 (project):
  To use the NMake generator, cmake must be run from a shell that can use the
  compiler cl from the command line.  This environment does not contain
  INCLUDE, LIB, or LIBPATH, and these must be set for the cl compiler to
  work.


The C compiler identification is unknown
The CXX compiler identification is unknown
CMake Error at CMakeLists.txt:139 (project):
  The CMAKE_C_COMPILER:

    cl

  is not a full path and was not found in the PATH.

  Tell CMake where to find the compiler by setting either the environment
  variable "CC" or the CMake cache entry CMAKE_C_COMPILER to the full path to
  the compiler, or to the compiler name if it is in the PATH.


CMake Error at CMakeLists.txt:139 (project):
  The CMAKE_CXX_COMPILER:

    cl

  is not a full path and was not found in the PATH.

  Tell CMake where to find the compiler by setting either the environment
  variable "CXX" or the CMake cache entry CMAKE_CXX_COMPILER to the full path
  to the compiler, or to the compiler name if it is in the PATH.


Configuring incomplete, errors occurred!
See also "D:/Others/brlcad-svn-trunk/.build/CMakeFiles/CMakeOutput.log".
See also "D:/Others/brlcad-svn-trunk/.build/CMakeFiles/CMakeError.log".

#######################################################################

8.My attempts to build BRL-CAD:

I tried to find the environment variable "CXX", but there is not such variable. Also I tried to change the CMAKE_C_COMPILER and the CMAKE_CXX_COMPILER to the full path to the compiler, but this also changed nothing.

I tried to build BRL-CAD with "cmake .. -DBRLCAD_ENABLE_STRICT=NO -DBRLCAD_BUNDLED_LIBS=ON -DCMAKE_BUILD_TYPE=Release -DCMAKE_C_COMPILER="c:\cygwin\bin\gcc.exe" -DCMAKE_CXX_COMPILER="c:\cygwin\bin\g++.exe" "

This removed some of the problems but still I am unable to build the project.

#######################################################################

BUILD LOG:

CMake Warning at CMakeLists.txt:139 (project):
  To use the NMake generator, cmake must be run from a shell that can use the
  compiler cl from the command line.  This environment does not contain
  INCLUDE, LIB, or LIBPATH, and these must be set for the cl compiler to
  work.


-- The C compiler identification is unknown
CMake Error at .build/CMakeFiles/3.1.0-rc2/CMakeCCompiler.cmake:1 (set):
  Syntax error in cmake code at

    D:/brlcad-svn-trunk/.build/CMakeFiles/3.1.0-rc2/CMakeCCompiler.cmake:1

  when parsing string

    c:\cygwin\bin\gcc.exe

  Invalid escape sequence \c
Call Stack (most recent call first):
  CMakeLists.txt:139 (project)


CMake Error: Error required internal CMake variable not set, cmake may be not be
 built correctly.
Missing variable is:
CMAKE_CXX_COMPILER_ENV_VAR
CMake Error: Could not find cmake module file: D:/brlcad-svn-trunk/.build/CMakeF
iles/3.1.0-rc2/CMakeCXXCompiler.cmake
-- Configuring incomplete, errors occurred!
See also "D:/brlcad-svn-trunk/.build/CMakeFiles/CMakeOutput.log".
See also "D:/brlcad-svn-trunk/.build/CMakeFiles/CMakeError.log".