crosstool-ng/config/libc/glibc.in.2

# This file contains the common configuration options
# that apply to both glibc.

# Some architectures require the ports addon. List them one by one here:
# This list must be carefully in sync with the architectures names
# we can find in config/arch/*

# Ports were integrated into the main tarball in 2.17
config LIBC_GLIBC_PORTS_EXTERNAL
    def_bool y
    depends on !LIBC_GLIBC_2_17_or_later

config LIBC_GLIBC_NEEDS_PORTS
    def_bool y
    depends on ARCH_alpha || ARCH_arm || ARCH_m68k || ARCH_mips || ARCH_powerpc

# Ports are no longer an add-on starting with 2.20
config LIBC_GLIBC_USE_PORTS
    def_bool y
    depends on LIBC_GLIBC_NEEDS_PORTS && !LIBC_GLIBC_2_20_or_later

# Force using the BFD linker during the toolchain build
config LIBC_glibc_family
    bool
    default y
    select BINUTILS_FORCE_LD_BFD_DEFAULT

config LIBC_GLIBC_EXTRA_CONFIG_ARRAY
    string
    prompt "extra config"
    default ""
    help
      Extra flags to pass onto ./configure when configuring.

      You can enter multiple arguments here, and arguments can contain spaces
      if they are properly quoted (or escaped, but prefer quotes). Eg.:
          --with-foo="1st arg with 4 spaces" --with-bar=2nd-arg-without-space

config LIBC_GLIBC_CONFIGPARMS
    string
    prompt "Extra config params (READ HELP)"
    default "" if ! ARCH_sh
    default "no-z-defs=yes" if ARCH_sh
    help
      Some architectures need to set options in the file configparms.
      This is the case for sh3/4, which really need to set configparms
      to "no-z-defs=yes" as of gcc-3.4/glibc-2.3.2.
      
      Unless you are building a toolchain for sh3/4, you should leave that empty.
      
      Note: If you need to pass more than one value, separate them with
            '\n'. Eg.:  var1=val1\nvar2=val2

config LIBC_GLIBC_EXTRA_CFLAGS
    string
    prompt "extra target CFLAGS"
    default ""
    help
      Extra target CFLAGS to use when building.

config LIBC_ENABLE_FORTIFIED_BUILD
    bool
    prompt "Enable fortified build (EXPERIMENTAL)"
    depends on EXPERIMENTAL
    help
      If you say 'y' here, then glibc will be using fortified versions
      of functions with format arguments (eg. vsyslog, printf...), and
      do a sanity check on the format at runtime, to avoid some of the
      common format string attacks.
      
      This is currently not supported, and will most probably result in
      a broken build, with an error message like:
        ../misc/syslog.c: In function '__vsyslog_chk':
        ../misc/syslog.c:123: sorry, unimplemented: inlining failed in
        call to 'syslog': function body not available
      
      If you are brave enough and want to debug the issue, then say 'y'
      here. Otherwise, be still and say 'n' (the default). ;-)


config LIBC_DISABLE_VERSIONING
    bool
    prompt "Disable symbols versioning"
    help
      Do not include versioning information in the library objects.

config LIBC_OLDEST_ABI
    string
    prompt "Oldest supported ABI"
    default ""
    help
      Set the oldest ABI supported by the C library.
      
      Setting this option, for example, to 2.2 will provide ABI support
      back to (e)glibc-2.2.

      If this option is not set, (e)glibc will choose for you.

config LIBC_GLIBC_FORCE_UNWIND
    bool
    prompt "Force unwind support (READ HELP!)"
    default y
    help
      If your toolchain fails building while building the C library
      start files, or the complete C library, with a message like:
        configure: error: forced unwind support is required
      
      then you may try changing this option. Otherwise, leave it to
      the default 'y'.
      
      The issue seems to be related to building NPTL on old versions
      of glibc on some architectures
      (seen on s390, s390x and x86_64).

config LIBC_ADDONS_LIST
    string
    prompt "Extra addons"
    default ""
    help
      Extra addons to include. Space separated list.

      You need to specify neither linuxthreads nor nptl, as they are added
      automagically for you depending on the threading model you chose
      earlier and on libc version selected.

      Also, do not specify ports even if applicable to the selected libc
      version/architecture; it is selected automatically.

      Eg.: libidn

config LIBC_LOCALES
    bool
    prompt "Build and install locales"
    help
      Whether to build and install the libc locale files for the target,
      which is required in order to support internationalization.

if LIBC_glibc && LIBC_LOCALES
comment "WARNING!                                                     "
comment "|  The built locales will be usable if and only if the build  "
comment "|  machine and the target:                                    "
comment "|   - have the same endianness,                               "
comment "|   - and have the same alignment requirements for uint32_t.  "
comment "|  You will have to check by yourself (for now).              "
endif # LIBC_glibc && LIBC_LOCALES

if KERNEL_linux

choice LIBC_GLIBC_SUPPORTED_KERNEL
    bool
    prompt "Minimum supported kernel version"
    default LIBC_GLIBC_KERNEL_VERSION_AS_HEADERS

config LIBC_GLIBC_KERNEL_VERSION_NONE
    bool
    prompt "Let ./configure decide"
    help
      Let ./configure decide what minimum kernel version glibc will be
      able to run against.
      
      This will include legacy compatibility code for older kernels in
      the C library, thus ensuring that it will run on a large number
      of old kernels.
      
      The minimum kernel version supported will be dependent upon the
      target you build for. For example:
        alpha*-*-linux-gnu      Requires Linux 2.6.9 for NPTL
        sh[34]-*-linux-gnu      Requires Linux 2.6.11
        powerpc*                Requires Linux 2.4.19
        arm*-*-linux-*gnueabi   Requires Linux 2.6.16

config LIBC_GLIBC_KERNEL_VERSION_AS_HEADERS
    bool
    prompt "Same as kernel headers (default)"
    help
      Normally, you'll want glibc to run against the same kernel
      version as the one used for the headers.
      
      This is the default.
      
      If enabled, crosstool-ng will use the chosen version of kernel
      headers for the glibc minimum kernel version supported, which is
      what gets passed to "--enable-kernel=" when configuring glibc.
      
      Enabling this will ensure that no legacy compatibility code for
      older kernels is built into your C libraries, but it will
      be unable to run on kernel versions older than whichever kernel
      headers version you've built the toolchain for.
      
      If you know for sure that your toolchain will never need to build
      applications that will run under a kernel version older than your
      chosen kernel headers version (CT_KERNEL_VERSION), you can choose
      "y" here.

config LIBC_GLIBC_KERNEL_VERSION_CHOSEN
    bool
    prompt "Specific kernel version"
    help
      Specify the earliest Linux kernel version you want glibc to
      include support for.  This does not have to match the kernel
      headers version used for your toolchain.  This controls what is
      passed to the "--enable-kernel=" option to the glibc configure
      script.

      If you want to be able to statically link programs with your
      toolchain's C library, make sure this kernel version is lower than
      all kernels you wish to support to avoid "FATAL: kernel too old"
      errors.  The higher the version you specify, the less legacy code
      will be built into libc.

      Most people can leave this at the default value of "2.6.9".

if LIBC_GLIBC_KERNEL_VERSION_CHOSEN

config LIBC_GLIBC_MIN_KERNEL_VERSION
    string
    prompt "Minimum kernel version to support"
    default "2.6.9"
    help
      Enter here the lowest kernel version glibc will be able to run against.
      
      The minimum kernel version supported will be dependent upon the
      target you build for. For example:
        alpha*-*-linux-gnu      Requires Linux 2.6.9 for NPTL
        sh[34]-*-linux-gnu      Requires Linux 2.6.11
        powerpc*                Requires Linux 2.4.19
        arm*-*-linux-*gnueabi   Requires Linux 2.6.16
      
      Note that no sanity check is performed by crosstool-NG to ensure
      that the value you enter here is appropriate for your target.

endif # LIBC_GLIBC_KERNEL_VERSION_CHOSEN

endchoice

config LIBC_GLIBC_MIN_KERNEL
    string
    default ""                            if LIBC_GLIBC_KERNEL_VERSION_NONE
    default KERNEL_VERSION                if LIBC_GLIBC_KERNEL_VERSION_AS_HEADERS
    default LIBC_GLIBC_MIN_KERNEL_VERSION if LIBC_GLIBC_KERNEL_VERSION_CHOSEN

endif # KERNEL_linux