INCLUDE(CheckCCompilerFlag)
INCLUDE(CheckCXXCompilerFlag)

# We want release compilation by default
IF(NOT CMAKE_BUILD_TYPE)
  SET(CMAKE_BUILD_TYPE Release CACHE STRING
      "Choose the type of build, options are: None Debug Release RelWithDebInfo MinSizeRel." FORCE)
ENDIF(NOT CMAKE_BUILD_TYPE)

# we want warnings
# we want exceptions support even when compiling c code

# C
IF(NOT MSVC)
  CHECK_C_COMPILER_FLAG(-Wall C_HAS_WALL)
  IF(C_HAS_WALL)
    SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall")
  ENDIF()
  CHECK_C_COMPILER_FLAG(-Wno-unused-but-set-variable C_HAS_WNOUNUSEDBUTSET)
  IF (C_HAS_WNOUNUSEDBUTSET)
    SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wno-unused-but-set-variable")
  ENDIF ()
ENDIF()

IF (UNIX)
  CHECK_C_COMPILER_FLAG(-fstd=c89 C_HAS_STDC89)
  IF (C_HAS_STDC89)
    SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -fstd=c89 -D_SVID_SOURCE -D_GNU_SOURCE")
  ENDIF ()
ENDIF()

CHECK_C_COMPILER_FLAG(-Wno-unused-function C_HAS_NO_UNUSED_FUNCTION)
IF(C_HAS_NO_UNUSED_FUNCTION)
  SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wno-unused-function")
ENDIF(C_HAS_NO_UNUSED_FUNCTION)

CHECK_C_COMPILER_FLAG(-fexceptions C_HAS_FEXCEPTIONS)
IF(C_HAS_FEXCEPTIONS)
  SET(CMAKE_C_FLAGS "-fexceptions ${CMAKE_C_FLAGS}")
ENDIF(C_HAS_FEXCEPTIONS)

CHECK_C_COMPILER_FLAG(-Wno-unknown-pragmas C_HAS_NO_UNKNOWN_PRAGMAS)
IF(C_HAS_NO_UNKNOWN_PRAGMAS)
  SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wno-unknown-pragmas")
ENDIF(C_HAS_NO_UNKNOWN_PRAGMAS)

# C++
IF(NOT MSVC)
  CHECK_CXX_COMPILER_FLAG(-Wall CXX_HAS_WALL)
  IF(CXX_HAS_WALL)
    SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall")
  ENDIF(CXX_HAS_WALL)
ENDIF()

CHECK_CXX_COMPILER_FLAG(-Wno-unused-function CXX_HAS_NO_UNUSED_FUNCTION)
IF(CXX_HAS_NO_UNUSED_FUNCTION)
  SET(CMAKE_CXX_FLAGS "${CMAKE_C_FLAGS} -Wno-unused-function")
ENDIF(CXX_HAS_NO_UNUSED_FUNCTION)

# When using MSVC
IF(MSVC)
  # we want to respect the standard, and we are bored of those **** .
  ADD_DEFINITIONS(-D_CRT_SECURE_NO_DEPRECATE=1)
ENDIF(MSVC)

# OpenMP support?
SET(WITH_OPENMP ON CACHE BOOL "OpenMP support if available?")
IF (APPLE AND CMAKE_COMPILER_IS_GNUCC)
  EXEC_PROGRAM (uname ARGS -v  OUTPUT_VARIABLE DARWIN_VERSION)
  STRING (REGEX MATCH "[0-9]+" DARWIN_VERSION ${DARWIN_VERSION})
  MESSAGE (STATUS "MAC OS Darwin Version: ${DARWIN_VERSION}")
  IF (DARWIN_VERSION GREATER 9)
    SET(APPLE_OPENMP_SUCKS 1)
  ENDIF (DARWIN_VERSION GREATER 9)
  EXECUTE_PROCESS (COMMAND ${CMAKE_C_COMPILER} -dumpversion
    OUTPUT_VARIABLE GCC_VERSION)
  IF (APPLE_OPENMP_SUCKS AND GCC_VERSION VERSION_LESS 4.6.2)
    MESSAGE(STATUS "Warning: Disabling OpenMP (unstable with this version of GCC)")
    MESSAGE(STATUS " Install GCC >= 4.6.2 or change your OS to enable OpenMP")
    SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wno-unknown-pragmas")
    SET(WITH_OPENMP OFF CACHE BOOL "OpenMP support if available?" FORCE)
  ENDIF ()
ENDIF ()

IF (WITH_OPENMP)
  FIND_PACKAGE(OpenMP)
  IF(OPENMP_FOUND)
    MESSAGE(STATUS "Compiling with OpenMP support")
    SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${OpenMP_C_FLAGS}")
    SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${OpenMP_CXX_FLAGS}")
    SET(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} ${OpenMP_EXE_LINKER_FLAGS}")
  ENDIF(OPENMP_FOUND)
ENDIF (WITH_OPENMP)

# ARM specific flags
FIND_PACKAGE(ARM)
IF (NEON_FOUND)
  MESSAGE(STATUS "Neon found with compiler flag : -mfpu=neon -D__NEON__")
  SET(CMAKE_C_FLAGS "-mfpu=neon -D__NEON__ ${CMAKE_C_FLAGS}")
ENDIF (NEON_FOUND)
IF (CORTEXA8_FOUND)
  MESSAGE(STATUS "Cortex-A8 Found with compiler flag : -mcpu=cortex-a8")
  SET(CMAKE_C_FLAGS "-mcpu=cortex-a8 -fprefetch-loop-arrays ${CMAKE_C_FLAGS}")
ENDIF (CORTEXA8_FOUND)
IF (CORTEXA9_FOUND)
  MESSAGE(STATUS "Cortex-A9 Found with compiler flag : -mcpu=cortex-a9")
  SET(CMAKE_C_FLAGS "-mcpu=cortex-a9 ${CMAKE_C_FLAGS}")
ENDIF (CORTEXA9_FOUND)