How to add clang dependency to ROS package

edit

I'm trying to release one ROS package, but the automatic build of the package on Jenkins fails, with this error:

CMake Error at CMakeLists.txt:16 (project):
The CMAKE_C_COMPILER:

 clang

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:16 (project):
The CMAKE_CXX_COMPILER:

 clang++

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.

I understand that the problem is that clang is not installed in the docker container used by Jenkins to compile the package, but I don't know what to configure in the package to add this system dependency, I have tried to add both

<build_depend>clang</build_depend>

and

<buildtool_depend>clang<buildtool_depend>

but in both cases I have the error

KeyError: 'clang'

can someone please help me to understand how to add this system dependency?