Basically to build brlcad in cygwin, there are a few things to take note. Firstly that brlcad has some files that will generate man-pages with names containing :: which is unacceptable in Windows and will cause errors like CMake Error: File /usr/brlcad/rel-7.22.1/brlcad-build/src/other/tcl/doc/mann/pkg::create.n does not exist. CMake Error at CMakeLists.txt:417 (_configure_file): configure_file Problem configuring file Call Stack (most recent call first): src/other/tcl/doc/CMakeLists.txt:291 (configure_file) To prevent such errors, go to src/other/tcl/doc and edit packagens.n, changing all instance of pkg::create to pkg_create. This file is the only special one where the file to edit has a name differing from the generated ones. Otherwise, ie ttk::button.n, the source would be called tk_button.n List of files to edit: tk (src/other/tk/doc) ttk::button.n ttk::checkbutton.n ttk::combobox.n ttk::entry.n ttk::frame.n ttk::intro.n ttk::label.n ttk::labelframe.n ttk::menubutton.n ttk::notebook.n ttk::panedwindow.n ttk::progressbar.n ttk::radiobutton.n ttk::scale.n ttk::scrollbar.n ttk::separator.n ttk::sizegrip.n ttk::style.n ttk::treeview.n ttk::widget.n tcl (src/other/tcl/doc) pkg::create.n can be edited using packagens.n platform::shell.n To use cmake, make another directory called brlcad-build in the parent directory. mkdir brlcad-build cd brlcad-build cmake ../brlcad -DCMAKE_BUILD_TYPE=Release -DBRLCAD_BUNDLED_LIBS=Bundled Give it some time and it will finish configuration successfully. Next, make utilising the quad core present. make -j4 It fails mainly due to a command in the script, make complains that -w is not a valid flag. zlib also fails to compile due to unknown reasons. It is possible to not build zlib when using cmake by adding -DBRLCAD_ZLIB=OFF This does not solve the problem totally and make will still fail ultimately due to -w flags.