#TESTING TIME

include(CheckCCompilerFlag)

#when you need to check for a linker flag, just leave the argument of "check_c_compiler_flag" empty

# CMAKE_C{XX}_FLAGS is for compiler flags (c and c++)

# CMAKE_EXE_LINKER_FLAGS is for linker flags (also add them to pascal_flags and haskell_flags)

# CMAKE_SHARED_LIBRARY_<lang>_FLAGS same but for shared libraries

#TODO: should there be two different checks for C and CXX?

#stack protection, when found it needs to go in the linker flags too

#it is disabled on win32 because it adds a dll and messes with linker

#some bsd installations reported problems too

#(see 822312 654424 on bugzilla.redhat.com)

check_c_compiler_flag("-fstack-protector-all -fstack-protector" HAVE_STACKPROTECTOR)

if(HAVE_STACKPROTECTOR AND ((NOT WIN32) OR (CMAKE_SYSTEM_NAME MATCHES BSD.OS)))

    add_flag_append(CMAKE_C_FLAGS "-fstack-protector-all -fstack-protector")

    add_flag_append(CMAKE_CXX_FLAGS "-fstack-protector-all -fstack-protector")

    add_flag_append(CMAKE_EXE_LINKER_FLAGS "-fstack-protector-all -fstack-protector")

    add_flag_append(CMAKE_SHARED_LIBRARY_C_FLAGS "-fstack-protector-all -fstack-protector")

    add_flag_append(CMAKE_SHARED_LIBRARY_CXX_FLAGS "-fstack-protector-all -fstack-protector")

endif()

#symbol visibility, not supported on Windows

check_c_compiler_flag("-fvisibility=hidden" HAVE_VISIBILITY)

if(HAVE_VISIBILITY AND (NOT WIN32))

    add_flag_append(CMAKE_C_FLAGS "-fvisibility=hidden")

    add_flag_append(CMAKE_CXX_FLAGS "-fvisibility=hidden")

endif()

#check for noexecstack on ELF, Gentoo security

set(CMAKE_REQUIRED_FLAGS "-Wl,-z,noexecstack")

check_c_compiler_flag("" HAVE_NOEXECSTACK)

if(HAVE_NOEXECSTACK)

    add_linker_flag("-znoexecstack")

endif()

#check for full relro on ELF, Debian security

set(CMAKE_REQUIRED_FLAGS "-Wl,-zrelro,-znow")

check_c_compiler_flag("" HAVE_RELROFULL)

if(HAVE_RELROFULL)

    add_linker_flag("-zrelro")

    add_linker_flag("-znow")

else()

    #if full relro is not available, try partial relro

    set(CMAKE_REQUIRED_FLAGS "-Wl,-zrelro")

    check_c_compiler_flag("" HAVE_RELROPARTIAL)

    if(HAVE_RELROPARTIAL)

        add_linker_flag("-zrelro")

    endif()

endif()

#check for ASLR on Windows Vista or later, requires binutils >= 2.20

set(CMAKE_REQUIRED_FLAGS "-Wl,--nxcompat")

check_c_compiler_flag("" HAVE_WINASLR)

if(HAVE_WINASLR)

    add_linker_flag("--nxcompat")

endif()

#check for DEP on Windows XP SP2 or later, requires binutils >= 2.20

set(CMAKE_REQUIRED_FLAGS "-Wl,--dynamicbase")

check_c_compiler_flag("" HAVE_WINDEP)

if(HAVE_WINDEP)

    add_linker_flag("--dynamicbase")

endif()

#this is actually an optimisation

set(CMAKE_REQUIRED_FLAGS "-Wl,--as-needed")

check_c_compiler_flag("" HAVE_ASNEEDED)

if(HAVE_ASNEEDED)

    add_linker_flag("--as-needed")

endif()

#always unset or these flags will be spread everywhere

unset(CMAKE_REQUIRED_FLAGS)