Issue with CMake and find_package - c++

Question

I'm very new to CMake, and I try to write a CMake file for my project.
My project consists of .h and .cpp files, generating an executable, and using the SFML library.
I've installed the findSFML script, I use the find_package function of CMake:
cmake_minimum_required(VERSION 2.6)
# Projet name
project("Witch_Blast")
file(
GLOB_RECURSE
source_files
src/*
)
add_executable(
"Witch_Blast"
${source_files}
)
# Detect and add SFML
set(CMAKE_MODULE_PATH "${CMAKE_SOURCE_DIR}/cmake_modules" ${CMAKE_MODULE_PATH})
find_package(SFML 2.1 REQUIRED system window graphics audio)
target_link_libraries(Witch_Blast ${SFML_LIBRARIES})
I try to generate a Windows Code::Blocks project.
It finds the library and generate projects files.
My problem:
It won't compile because it won't find the SFML header files, and I cannot modify the project setting...
What have I done wrong ?
Thanks !
EDIT:
CMake generation output:
-- The C compiler identification is GNU 4.7.1
-- The CXX compiler identification is GNU 4.7.1
-- Check for working C compiler: C:/Program Files (x86)/CodeBlocks/MinGW/bin/gcc.exe
-- Check for working C compiler: C:/Program Files (x86)/CodeBlocks/MinGW/bin/gcc.exe -- works
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Check for working CXX compiler: C:/Program Files (x86)/CodeBlocks/MinGW/bin/g++.exe
-- Check for working CXX compiler: C:/Program Files (x86)/CodeBlocks/MinGW/bin/g++.exe -- works
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Found SFML 2.1 in C:/Lib/SFML-2.1_TDM/include
-- Configuring done
-- Generating done
-- Build files have been written to: C:/Users/Seb/Dev/Witch Blast/cmakedir
message(SFML_LIBRARIES):
debugC:/Lib/SFML-2.1_TDM/lib/libsfml-system-d.aoptimizedC:/Lib/SFML-2.1_TDM/lib/
libsfml-system.adebugC:/Lib/SFML-2.1_TDM/lib/libsfml-window-d.aoptimizedC:/Lib/S
FML-2.1_TDM/lib/libsfml-window.adebugC:/Lib/SFML-2.1_TDM/lib/libsfml-graphics-d.
aoptimizedC:/Lib/SFML-2.1_TDM/lib/libsfml-graphics.adebugC:/Lib/SFML-2.1_TDM/lib
/libsfml-audio-d.aoptimizedC:/Lib/SFML-2.1_TDM/lib/libsfml-audio.a
(But it's not a linker error, it's an include path error)

Answer 1

You need to add the header directory to you compiler's path.
include_directories(${SFML_INCLUDE_DIR})
All variables find_package(SFML) sets can be found here.