Requirements

The CMake configuration of Gaudi is based on the version 2.8.5 or later of CMake. On lxplus (SLC6 and CentOS7) you need to call something like:

$ export PATH=/cvmfs/sft.cern.ch/lcg/contrib/CMake/3.7.0/Linux-x86_64/bin:$PATH

You also need to ensure that the compiler you want to use is configured and available on the PATH, for example with something like:

$ . /cvmfs/sft.cern.ch/lcg/contrib/gcc/7.1.0/x86_64-centos7/setup.sh

NOTE: If you use the LHCb environment (as of LbScripts v7r7), you do not need to prepare the environment for the compiler.

Quick Start

To quickly get started, you can use the Makefile, which will take care of the main details (except the value of BINARY_TAG, or CMTCONFIG for backward compatibility):

$ make -j 8
$ make test

The main targets are:

configure

just run CMake to generate the build directory (or reconfigure)
all (default)

build everything (implies configure)
test

run the tests (and generate HTML reports), note that it does not imply the build and does not require installation
install

populate the InstallArea directory, required for runtime/deployment

Some extra targets are provided for special cases:

unsafe-install

allow partial installation after a failed build (for builds in a continuous integration system)
post-install

optional operations on the content of InstallArea (like compressing the python directory)

Build

I suggest to use the off-source build, which means that the files required by the build and the build products are created in a different directory than the source one. In this example I'll use Gaudi-build, created at the same level as the directory containing the sources (Gaudi).

To prepare the build directory, you have to:

$ src=$PWD/Gaudi
$ mkdir Gaudi-build
$ cd Gaudi-build
$ cmake -DCMAKE_TOOLCHAIN_FILE=$src/toolchain.cmake \
    -G "Eclipse CDT4 - Unix Makefiles" $src

This will create the required Unix makefiles and the Eclipse project configuration to build Gaudi.

Other options are available on the command line when you prepare the build directory the first time or afterwards via the CMake configuration tool ccmake, for example CMAKE_USE_DISTCC or CMAKE_USE_CCACHE.

Now you can build the project with a simple (from Gaudi-build)::

$ make

or from Eclipse after you imported the project.

The tests can be run via the command ctest or with make test.

Note that the build via Makefile uses the build directory build.${BINARY_TAG} under the source directory.

Install

The build of the project obtained with CMake cannot be used directly by other projects: it needs to be installed in the source directory (for backward compatibility with CMT) with the command:

$ make install

It must be noted that the special file python.zip is not automatically generated, so, if you want it, you have to call, after the installation:

$ make post-install

Run

The runtime environment for the installed binaries is described by the XML file Gaudi.xenv located in the directory InstallArea/$BINARY_TAG, in the format understood by the Python script xenv available in the cmake directory in the source tree (it is also installed).

The behavior of xenv is quite similar to that of the standard Unix command env (see man env), with the addition of few functionalities (append, prepend, XML).

For example, you can call gaudirun.py like this (with the variable src defined above):

$ $src/cmake/xenv --xml $src/InstallArea/$BINARY_TAG/Gaudi.xenv \
    gaudirun.py --help

or, to have a sub-shell with the right environment:

$ $src/cmake/xenv --xml $src/InstallArea/$BINARY_TAG/Gaudi.xenv bash

(note that you may need to add the --norc option to bash).

Run from the build directory

For testing and debugging (as already mentioned) there is no need to install.

To run an application using the build directory, you can use the script xenv with the XML file Gaudi-build.xenv located in the conf subdirectory of the build directory, or the convenience script run (in the build directory), for example like this:

$ cd Gaudi-build
$ ./run gaudirun.py --help
$ ./run bash

When using Makefile the above lines should be changed in

$ build.$BINARY_TAG/run gaudirun.py --help
$ build.$BINARY_TAG/run bash

Resources

CMake documentation
FindTBB.cmake was taken from https://bitbucket.org/sergiu/tbb-cmake