glibc/sysdeps/unix/sysv/linux/mips/configure.ac

sinclude(./aclocal.m4)dnl Autoconf lossage
GLIBC_PROVIDES dnl See aclocal.m4 in the top level source directory.
# Local configure fragment for sysdeps/unix/sysv/linux/mips.

AC_COMPILE_IFELSE(
  [AC_LANG_PROGRAM([
    #if (_MIPS_SIM != _ABIO32)
    #error Not O32 ABI
    #endif])],
  [libc_mips_abi=o32],
  [AC_COMPILE_IFELSE(
    [AC_LANG_PROGRAM([
      #if (_MIPS_SIM != _ABIN32)
      #error Not N32 ABI
      #endif])],
    [libc_mips_abi=n32],
    [AC_COMPILE_IFELSE(
      [AC_LANG_PROGRAM([
        #if (_MIPS_SIM != _ABI64)
        #error Not 64 ABI
        #endif])],
      [libc_mips_abi=n64],
      [])])])

if test -z "$libc_mips_abi"; then
  AC_MSG_ERROR([could not determine what ABI the compiler is using])
fi

AC_COMPILE_IFELSE(
  [AC_LANG_PROGRAM([
    #if !defined(__mips_soft_float)
    #error Not soft ABI
    #endif])],
  [libc_mips_float=soft],
  [AC_COMPILE_IFELSE(
    [AC_LANG_PROGRAM([
      #if !defined(__mips_hard_float)
      #error Not hard ABI
      #endif])],
    [libc_mips_float=hard],
    [])])

if test -z "$libc_mips_float"; then
  AC_MSG_ERROR([could not determine if compiler is using hard or soft floating point ABI])
fi

libc_mips_o32_fp=
libc_cv_mips_fp64=
libc_cv_mips_modd_spreg=

if test x"$libc_mips_abi" = xo32 -a x"$libc_mips_float" = xhard; then
  AC_COMPILE_IFELSE(
    [AC_LANG_PROGRAM([
      #if !defined(__mips_fpr)
      #error Missing FPR sizes
      #endif])],
    [AC_COMPILE_IFELSE(
      [AC_LANG_PROGRAM([
        #if (__mips_fpr != 32)
        #error Not FP32
        #endif])],
      [libc_mips_o32_fp=32],
      [AC_COMPILE_IFELSE(
        [AC_LANG_PROGRAM([
          #if (__mips_fpr != 0) || !defined(_MIPS_SPFPSET) || (_MIPS_SPFPSET != 16)
          #error Not FPXX (without odd single-precision registers)
          #endif])],
        [libc_mips_o32_fp=xx],
        [AC_COMPILE_IFELSE(
          [AC_LANG_PROGRAM([
            #if (__mips_fpr != 0)
            #error Not FPXX (with odd single precision registers)
            #endif])],
          [libc_mips_o32_fp=xxo],
          [AC_COMPILE_IFELSE(
            [AC_LANG_PROGRAM([
              #if (__mips_fpr != 64) || !defined(_MIPS_SPFPSET) || (_MIPS_SPFPSET != 16)
              #error Not FP64A
              #endif])],
            [libc_mips_o32_fp=64a],
            [AC_COMPILE_IFELSE(
              [AC_LANG_PROGRAM([
                #if (__mips_fpr != 64)
                #error Not FP64
                #endif])],
              [libc_mips_o32_fp=64],
              [])])])])])],
    [])

  LIBC_TRY_CC_OPTION([-mfp64], [libc_cv_mips_fp64=yes], [libc_cv_mips_fp64=no])
  LIBC_TRY_CC_OPTION([-Werror -modd-spreg], [libc_cv_mips_modd_spreg=yes], [libc_cv_mips_modd_spreg=no])
fi
LIBC_CONFIG_VAR([o32-fpabi],[${libc_mips_o32_fp}])
LIBC_CONFIG_VAR([has-mpf64],[${libc_cv_mips_fp64}])
LIBC_CONFIG_VAR([has-modd-spreg],[${libc_cv_mips_modd_spreg}])

AC_COMPILE_IFELSE(
  [AC_LANG_PROGRAM([
    #include <linux/prctl.h>
    #if !defined(PR_GET_FP_MODE) || !defined(PR_SET_FP_MODE)
    #error New prctl support for setting FP modes not found
    #endif])],
  [libc_mips_mode_switch=yes],
  [libc_mips_mode_switch=no])
LIBC_CONFIG_VAR([mips-mode-switch],[${libc_mips_mode_switch}])

AC_CACHE_CHECK([whether the compiler is using the 2008 NaN encoding],
  libc_cv_mips_nan2008, [AC_EGREP_CPP(yes, [dnl
#ifdef __mips_nan2008
yes
#endif], libc_cv_mips_nan2008=yes, libc_cv_mips_nan2008=no)])

libc_mips_nan=
if test x"$libc_cv_mips_nan2008" = xyes; then
  libc_mips_nan=_2008
fi

LIBC_CONFIG_VAR([default-abi],
  [${libc_mips_abi}_${libc_mips_float}${libc_mips_nan}])

case $machine in
mips/mips64/n64/*)
  LIBC_SLIBDIR_RTLDDIR([lib64], [lib64])
  ;;
mips/mips64/n32/*)
  LIBC_SLIBDIR_RTLDDIR([lib32], [lib32])
  ;;
esac

libc_cv_gcc_unwind_find_fde=yes

if test -z "$arch_minimum_kernel"; then
  if test x$libc_cv_mips_nan2008 = xyes; then
    arch_minimum_kernel=4.5.0
  fi
fi

# Check if we are supposed to run on kernels older than 4.8.0. If so,
# force executable stack to avoid potential runtime problems with fpu
# emulation.
# NOTE: The check below assumes that in absence of user-provided minumum_kernel
# we will default to arch_minimum_kernel which is currently less than 4.8.0 for
# all known configurations. If this changes, the check must be updated.
AC_CACHE_CHECK([whether the compiler must use executable stack],
        libc_cv_mips_force_execstack, [dnl
libc_cv_mips_force_execstack=no
  if test $libc_mips_float = hard; then
    if test -n "$minimum_kernel"; then
       changequote(,)
       min_version=$((`echo "$minimum_kernel.0.0.0" | sed 's/\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\).*/\1 \* 65536 + \2 \* 256 + \3/'`))
       changequote([,])
       if test $min_version -lt 264192; then
         libc_cv_mips_force_execstack=yes
       fi
    else
      libc_cv_mips_force_execstack=yes
    fi
  fi])

libc_mips_has_gnustack=$libc_cv_as_noexecstack

if test $libc_cv_mips_force_execstack = yes; then
  libc_mips_has_gnustack=no
  AC_MSG_WARN([forcing executable stack for pre-4.8.0 Linux kernels])
fi

LIBC_CONFIG_VAR([mips-force-execstack],[${libc_cv_mips_force_execstack}])
LIBC_CONFIG_VAR([mips-has-gnustack],[${libc_mips_has_gnustack}])