Comment utiliser cmake_policy ?

Lors d’une compilation (un jeu), au cmake, j’ai l’erreur suivante :

Policy CMP0015 is not set: link_directories() treats paths relative to the source dir. Run "cmake --help-policy CMP0015" for policy details. Use the cmake_policy command to set the policy and suppress this warning. This warning is for project developers. Use -Wno-dev to suppress it.

Le résultat du help suggéré;

[code]root@990FX6100:/home/andre/Documents/Supertux2/supertux-0.3.3# cmake --help-policy CMP0015
cmake version 2.8.8
CMP0015
link_directories() treats paths relative to the source dir.

   In CMake 2.8.0 and lower the link_directories() command passed
   relative paths unchanged to the linker.  In CMake 2.8.1 and above the
   link_directories() command prefers to interpret relative paths with
   respect to CMAKE_CURRENT_SOURCE_DIR, which is consistent with
   include_directories() and other commands.  The OLD behavior for this
   policy is to use relative paths verbatim in the linker command.  The
   NEW behavior for this policy is to convert relative paths to absolute
   paths by appending the relative path to CMAKE_CURRENT_SOURCE_DIR.

   This policy was introduced in CMake version 2.8.1.  CMake version
   2.8.8 warns when the policy is not set and uses OLD behavior.  Use the
   cmake_policy command to set it to OLD or NEW explicitly. [/code]

Après consultation du wiki

cmake.org/Wiki/CMake_Policies

section Setting Policies (à peu près au milieu), je n’obtiens rien des commandes proposées:

root@990FX6100:/home/andre/Documents/Supertux2/supertux-0.3.3/build# cmake_policy(SET CMP0015 NEW) bash: Erreur de syntaxe près du symbole inattendu « SET »

ou bien (je suis en 2.8.8)

root@990FX6100:/home/andre/Documents/Supertux2/supertux-0.3.3/build# cmake_policy(VERSION 2.8) bash: Erreur de syntaxe près du symbole inattendu « VERSION »

Quelle erreur de syntaxe, ce sont pourtant bien les commandes proposées ?