CMake Howto
Cmake Crash Course
Understanding cmake
Cmake builds makefiles in the current directory. It leaves a cache file called CMakeCache.txt, even when cmake fails. Always delete this, as command line options don't override what's in there. It's common to bang your head on cmake only to remember that the cache file contains your first mistake.
There are two intermixed cmake instances in reactos, one for host tools and one for reactos itself. ReactOS is built by specifying an alternate toolchain definition for reasons nobody has explained to me. The one for unixen is toolchain-mingw32.cmake and you tell cmake to use it with -DCMAKE_TOOLCHAIN_FILE= .. It'd be nice to name that variable something more understandable.
Makefile emitted by cmake can have VERBOSE=1 specified.
Building tools
make a tools dir somewhere (like ./build/tools)
cmake -G "Unix Makefiles" [reactos-dir] TOOLS=`pwd`
or for a windows environment (using RosBE 2.1.1 (r64030) or RosBE 2.0 (r55995))
mkdir ./build/host-tools cd ./build/host-tools cmake -G "MinGW Makefiles" <pathtoyourreactossourcedir> set TOOLS=<pathtoyourreactossourcedir> mingw32-make
A specific example for windows Mingw RosBE 2.1.1:
mkdir c:\dev\ReactOS_work\bld_r64030\host-tools cd c:\dev\ReactOS_work\bld_r64030\host-tools cmake -G "MinGW Makefiles" c:\dev\ReactOS_work\svn_r64030 set TOOLS=c:\dev\ReactOS_work\bld_r64030\host-tools mingw32-make
Building ReactOS
make a different directory (like ./build/ros).
NOTE: This directory will contain a different logical cmake instance.
cmake -G "Unix Makefiles" -DREACTOS_BUILD_TOOLS_DIR:DIR=$TOOLS -DCMAKE_TOOLCHAIN_FILE=toolchain-mingw32.cmake [reactos-dir]
NOTE: The path to the tools dir *must* be specified as a full path
When cmake fails, errors look like this:
CMake Error at CMakeLists.txt:90 (include): include could not find load file: ../build/ImportExecutables.cmake
The most common reason for this step to fail is not specifying the path to the tools.
And a specific example for windows (RosBE 2.0 (r55995)) (but first note that this video may be helpful https://www.youtube.com/watch?v=q-DirQY_TL0)
mkdir c:\dev\ReactOS_work\bld_r55995\reactos cd c:\dev\ReactOS_work\bld_r55995\reactos cmake -G "MinGW Makefiles" -DREACTOS_BUILD_TOOLS_DIR:DIR=%TOOLS% -DCMAKE_TOOLCHAIN_FILE=toolchain-gcc.cmake c:\dev\ReactOS_work\svn_r55995 mingw32-make livecd