dnl Process this file with autoconf to produce a configure script.
AC_INIT()
{
AC_CONFIG_AUX_DIR(tool)

AC_PREREQ(2.67)

AC_DEFUN([RUBY_PREREQ_AC],
	[m4_if(m4_version_compare(m4_defn([m4_PACKAGE_VERSION]), [$1]), [-1],
		AC_MSG_ERROR([Autoconf version ]$1[ or higher is required]$2))])

AC_DISABLE_OPTION_CHECKING

AC_ARG_VAR([cflags], [additional CFLAGS])
AC_ARG_VAR([cppflags], [additional CPPFLAGS])
AC_ARG_VAR([cxxflags], [additional CXXFLAGS])

AC_DEFUN([RUBY_RM_RECURSIVE], [
m4_if(m4_version_compare(m4_defn([m4_PACKAGE_VERSION]), [2.70]), [-1], [
# suppress error messages, rm: cannot remove 'conftest.dSYM', from
# AC_EGREP_CPP with CFLAGS=-g on Darwin.
#
# TODO: remove this hack when AC_PREREQ() becomes 2.70 or later.
AS_CASE([$build_os], [darwin*], [
rm() {
    rm_recursive=''
    for arg do
	AS_CASE("$arg",
		[--*], [],
		[-*r*], [break],
		[conftest.*], [if test -d "$arg"; then rm_recursive=-r; break; fi],
		[])
    done
    command rm $rm_recursive "[$]@"
}
])])])

{ # environment section

AC_ARG_WITH(baseruby,
	AS_HELP_STRING([--with-baseruby=RUBY], [use RUBY as baseruby; RUBY is the pathname of ruby]),
	[
		AS_CASE(["$withval"],[*ruby*],[BASERUBY=$withval],[AC_MSG_ERROR(need ruby)])
	],
	[
		AC_PATH_PROG([BASERUBY], [ruby], [false])
	])
if test "`RUBYOPT=- $BASERUBY -e 'print 42' 2>/dev/null`" = 42; then
    if test "`RUBYOPT=- $BASERUBY --disable=gems -e 'print 42' 2>/dev/null`" = 42; then
	BASERUBY="$BASERUBY --disable=gems"
    fi
    $BASERUBY -C "$srcdir/tool" downloader.rb -e gnu config.guess config.sub
    HAVE_BASERUBY=yes
else
    BASERUBY="echo executable host ruby is required.  use --with-baseruby option.; false"
    HAVE_BASERUBY=no
fi
AC_SUBST(BASERUBY)
AC_SUBST(HAVE_BASERUBY)

AC_DEFUN([RUBY_MINGW32],
[AS_CASE(["$host_os"],
[cygwin*], [
AC_CACHE_CHECK(for mingw32 environment, rb_cv_mingw32,
[AC_TRY_CPP([
#ifndef __MINGW32__
# error
#endif
], rb_cv_mingw32=yes,rb_cv_mingw32=no)
rm -f conftest*])
if test "$rb_cv_mingw32" = yes; then
    target_os="mingw32"
    : ${ac_tool_prefix:="`expr "$CC" : ['\(.*-\)g\?cc[^/]*$']`"}
fi
])
AS_CASE(["$target_os"], [mingw*msvc], [
target_os="`echo ${target_os} | sed 's/msvc$//'`"
])
AS_CASE(["$target_cpu-$target_os"], [x86_64-mingw*], [
target_cpu=x64
])
])

AC_DEFUN([RUBY_NACL],
[
 AS_CASE(["${host_os}"],
[nacl], [
  ac_cv_exeext=.nexe
  host_vendor=chromium
  ac_cv_host=chromium
  AC_MSG_CHECKING([wheather \$NACL_SDK_ROOT is set])
  if test x"${NACL_SDK_ROOT}" = x; then
    AC_MSG_RESULT([no])
    AC_MSG_ERROR([You need to set \$NACL_SDK_ROOT environment variable to build for NativeClient])
  fi
  AC_MSG_RESULT([yes])

  nacl_cv_build_variant=glibc
  AC_ARG_WITH(newlib,
              AS_HELP_STRING([--with-newlib], [uses newlib version of NativeClient SDK]),
              [AS_CASE([$withval],
                       [no], [nacl_cv_build_variant=glibc],
                       [yes], [nacl_cv_build_variant=newlib])])

  AS_CASE(["$target_cpu"],
          [x86_64], [nacl_cv_cpu_nick=x86
                     nacl_cv_cpu_nick2=x86_64],
          [i?86], [nacl_cv_cpu_nick=x86
                   nacl_cv_cpu_nick2=x86_32],
          [le32], [nacl_cv_cpu_nick=pnacl
                   nacl_cv_cpu_nick2=pnacl
                   ac_cv_exeext=.pexe],
          [nacl_cv_cpu_nick=$target_cpu])
  AS_CASE(["$build_os"],
          [linux*], [nacl_cv_os_nick=linux],
          [darwin*], [nacl_cv_os_nick=mac],
          [cygwin*|mingw*], [nacl_cv_os_nick=win],
          [nacl_cv_os_nick=$build_os])

  host="$host_cpu-chromium-$host_os-"
  ac_tool_prefix="$host_cpu-nacl-"

  AC_MSG_CHECKING([NativeClient toolchain])
  if test x"$nacl_cv_cpu_nick" = xpnacl; then
    NACL_TOOLCHAIN="${nacl_cv_os_nick}_pnacl"
    ac_tool_prefix=pnacl-
  elif test -d \
    "${NACL_SDK_ROOT}/toolchain/${nacl_cv_os_nick}_${nacl_cv_cpu_nick}_${nacl_cv_build_variant}"; then
    NACL_TOOLCHAIN="${nacl_cv_os_nick}_${nacl_cv_cpu_nick}_${nacl_cv_build_variant}"
  elif test -d \
    "${NACL_SDK_ROOT}/toolchain/${nacl_cv_os_nick}_x86_${nacl_cv_cpu_nick}/${nacl_cv_build_variant}"; then
    NACL_TOOLCHAIN="${nacl_cv_os_nick}_x86_${nacl_cv_cpu_nick}/${nacl_cv_build_variant}"
  else
    AS_CASE(
      ["${nacl_cv_build_variant}"],
      [glibc], [if test \
        -d "${NACL_SDK_ROOT}/toolchain/${nacl_cv_os_nick}_${nacl_cv_cpu_nick}_newlib" \
        -a -d "${NACL_SDK_ROOT}/toolchain/${nacl_cv_os_nick}_${nacl_cv_cpu_nick}"; then
        NACL_TOOLCHAIN="${nacl_cv_os_nick}_${nacl_cv_cpu_nick}"
      fi],
      [newlib], [ NACL_TOOLCHAIN="${nacl_cv_os_nick}_${nacl_cv_cpu_nick}" ])
  fi
  if test ! -e "${NACL_SDK_ROOT}/toolchain/${NACL_TOOLCHAIN}/${ac_tool_prefix}gcc"; then
    if test "${build_cpu}" = i686 -a -e "${NACL_SDK_ROOT}/toolchain/${NACL_TOOLCHAIN}/nacl-gcc"; then
      ac_tool_prefix=nacl-
    fi
    if test "${build_cpu}" = x86_64 -a -e "${NACL_SDK_ROOT}/toolchain/${NACL_TOOLCHAIN}/nacl-gcc"; then
      ac_tool_prefix=nacl64-
    fi
  fi
  if test -z "${NACL_TOOLCHAIN}"; then
    AC_MSG_ERROR([Unrecognized --host and --build combination or NaCl SDK is not installed])
  fi
  AC_MSG_RESULT(${NACL_TOOLCHAIN})

  AC_MSG_CHECKING([path to SDK])
  if ! echo -- "${PATH}" | grep -F "${NACL_SDK_ROOT}/toolchain/${NACL_TOOLCHAIN}/bin" > /dev/null; then
    PATH="${PATH}:${NACL_SDK_ROOT}/toolchain/${NACL_TOOLCHAIN}/bin"
  fi
  AC_MSG_RESULT(${NACL_SDK_ROOT}/toolchain/${NACL_TOOLCHAIN}/bin)

  RUBY_APPEND_OPTIONS(XCFLAGS, '-I$(NACL_SDK_ROOT)/include')
  if test x"${nacl_cv_cpu_nick}" = xpnacl; then
    RUBY_APPEND_OPTIONS(XCFLAGS, '-isystem $(NACL_SDK_ROOT)/include/pnacl')
  elif test x"${nacl_cv_build_variant}" = xnewlib; then
    RUBY_APPEND_OPTIONS(XCFLAGS, '-isystem $(NACL_SDK_ROOT)/include/newlib')
  fi

  AC_MSG_CHECKING([nacl library path])
  if test -d "${NACL_SDK_ROOT}/lib/${nacl_cv_build_variant}_${nacl_cv_cpu_nick2}/Release"; then
    nacl_cv_libpath="${nacl_cv_build_variant}_${nacl_cv_cpu_nick2}"
  elif test -d "${NACL_SDK_ROOT}/lib/${nacl_cv_cpu_nick2}/Release"; then
    nacl_cv_libpath="${nacl_cv_cpu_nick2}"
  else
    AC_MSG_ERROR([not found])
  fi
  AC_MSG_RESULT([${nacl_cv_libpath}])
  RUBY_APPEND_OPTIONS(XLDFLAGS, '-L$(NACL_SDK_ROOT)/'"lib/${nacl_cv_libpath}/Release")

  AC_SUBST(NACL_TOOLCHAIN)
  AC_SUBST(NACL_SDK_ROOT)
  AC_SUBST(NACL_SDK_VARIANT, "${nacl_cv_build_variant}")
  AC_SUBST(NACL_LIB_PATH, "${nacl_cv_libpath}")
  AC_CHECK_TOOLS(CC, [clang gcc])
  AC_CHECK_TOOLS(CXX, [clang++ g++])
])])

AC_DEFUN([RUBY_NACL_CHECK_PEPPER_TYPES],
[AS_CASE(["${host_os}"],
[nacl], [
 AC_CHECK_TYPES([struct PPB_Core, struct PPB_Messaging, struct PPB_Var,
              struct PPB_URLLoader, struct PPB_URLRequestInfo,
              struct PPB_URLResponseInfo, struct PPB_FileRef,
              struct PPP_Instance])
])
])

AC_DEFUN([RUBY_CPPOUTFILE],
[AC_CACHE_CHECK(whether ${CPP} accepts -o, rb_cv_cppoutfile,
[save_CPPFLAGS="$CPPFLAGS"
CPPFLAGS='-o conftest-1.i'
rb_cv_cppoutfile=no
AC_TRY_CPP([test-for-cppout],
	   [grep test-for-cppout conftest-1.i > /dev/null && rb_cv_cppoutfile=yes])
CPPFLAGS="$save_CPPFLAGS"
rm -f conftest*])
if test "$rb_cv_cppoutfile" = yes; then
  CPPOUTFILE='-o conftest.i'
elif test "$rb_cv_cppoutfile" = no; then
  CPPOUTFILE='> conftest.i'
elif test -n "$rb_cv_cppoutfile"; then
  CPPOUTFILE="$rb_cv_cppoutfile"
fi
AC_SUBST(CPPOUTFILE)])

AC_DEFUN([RUBY_PROG_GNU_LD],
[AC_CACHE_CHECK(whether the linker is GNU ld, rb_cv_prog_gnu_ld,
[if `$CC $CFLAGS $CPPFLAGS $LDFLAGS --print-prog-name=ld 2>&1` -v 2>&1 | grep "GNU ld" > /dev/null; then
  rb_cv_prog_gnu_ld=yes
else
  rb_cv_prog_gnu_ld=no
fi
])
GNU_LD=$rb_cv_prog_gnu_ld
AC_SUBST(GNU_LD)])

eval `sed -n ['s/^@%:@define RUBY_API_VERSION_\([A-Z][A-Z_0-9]*\) \([0-9][0-9]*\)/API_\1=\2/p'] $srcdir/include/ruby/version.h`
RUBY_PROGRAM_VERSION=`sed -n 's/^@%:@define RUBY_VERSION "\(.*\)"/\1/p' $srcdir/version.h`
MAJOR=`echo $RUBY_PROGRAM_VERSION | cut -d. -f1`
MINOR=`echo $RUBY_PROGRAM_VERSION | cut -d. -f2`
TEENY=`echo $RUBY_PROGRAM_VERSION | cut -d. -f3`
for v in MAJOR MINOR TEENY; do
    if eval "test \"\$$v\" = ''"; then
	AC_MSG_ERROR(could not determine $v number from version.h)
    fi
done
AS_IF([test "$MAJOR.$MINOR" != "$API_MAJOR.$API_MINOR"], [
    AC_MSG_ERROR([API version $API_MAJOR.$API_MINOR differs from program version $MAJOR.$MINOR])
])
AC_SUBST(MAJOR)
AC_SUBST(MINOR)
AC_SUBST(TEENY)
AC_SUBST(RUBY_PROGRAM_VERSION)
RUBY_PATCHLEVEL=`sed -n 's/^#define RUBY_PATCHLEVEL //p' $srcdir/version.h`
AC_DEFINE(CANONICALIZATION_FOR_MATHN)
dnl checks for alternative programs
AC_CANONICAL_BUILD
RUBY_RM_RECURSIVE
AC_ARG_WITH(gcc,
	AS_HELP_STRING([--without-gcc], [never use gcc]),
	[
	AS_CASE([$withval],
	    [no],  [: ${CC=cc}],
	    [yes], [: ${CC=gcc}],
	           [CC=$withval])])
dnl If the user switches compilers, we can't believe the cache
if test ! -z "$ac_cv_prog_CC" -a ! -z "$CC" -a "$CC" != "$ac_cv_prog_CC"
then
  AC_MSG_ERROR(cached CC is different -- throw away $cache_file
(it is also a good idea to do 'make clean' before compiling))
fi
test -z "$CC" || ac_cv_prog_CC="$CC"

if test "$program_prefix" = NONE; then
  program_prefix=
fi
if test "$prefix" -ef .; then
  AC_MSG_ERROR(--prefix cannot be the current working directory.)
fi
RUBY_BASE_NAME=`echo ruby | sed "$program_transform_name"`
RUBYW_BASE_NAME=`echo rubyw | sed "$program_transform_name"`
AC_SUBST(RUBY_BASE_NAME)
AC_SUBST(RUBYW_BASE_NAME)
AC_SUBST(RUBY_VERSION_NAME, '${RUBY_BASE_NAME}-${ruby_version}')

AC_CANONICAL_TARGET
test x"$target_alias" = x &&
target_os=`echo $target_os | sed 's/linux-gnu$/linux/;s/linux-gnu/linux-/'`
ac_install_sh='' # unusable for extension libraries.

AC_ARG_WITH(os-version-style,
	AS_HELP_STRING([--with-os-version-style=TYPE],
		       [OS version number for target and target_os [[full]]]
		       [(full|teeny|minor+0|minor|major+0|major|none)]),
	[os_version_style=$withval],
	[os_version_style=full
	    AS_CASE($target_os, [[*[0-9].*]],
		[AS_CASE([`/usr/bin/ruby -e 'puts RUBY_PLATFORM' 2>/dev/null`],
		    [[*-*[0-9].*.0]], [os_version_style=minor+0],
		    [[*-*[0-9].*.*]], [os_version_style=full],
		    [[*-*[0-9].0]  ], [os_version_style=major+0],
		    [[*-*[0-9].*]  ], [os_version_style=minor],
		    [[*-*[0-9]]    ], [os_version_style=major],
		)])
	])
os_version_style_transform=
AS_CASE("${os_version_style}",
	[full|teeny], [],
	[minor+0], [os_version_style_transform=['s/\([0-9]\.[0-9][0-9]*\)\.[0-9][.0-9]*$/\1.0/']],
	[minor],   [os_version_style_transform=['s/\([0-9]\.[0-9][0-9]*\)\.[0-9][.0-9]*$/\1/']],
	[major+0], [os_version_style_transform=['s/\([0-9]\)\.[0-9][.0-9]*$/\1.0/']],
	[major],   [os_version_style_transform=['s/\([0-9]\)\.[0-9][.0-9]*$/\1/']],
	[none],    [os_version_style_transform=['s/[0-9]\.[0-9][.0-9]*$//']],
	[AC_MSG_ERROR(unknown --with-os-version-style: $withval)])
AS_IF([test -z "$target_alias" -a -n "$os_version_style_transform"],
	[
	target=`echo ${target} | sed "$os_version_style_transform"`
	target_os=`echo ${target_os} | sed "$os_version_style_transform"`
	])

AC_DEFUN([RUBY_APPEND_OPTION],
	[# RUBY_APPEND_OPTION($1)
	AS_CASE([" [$]{$1-} "],
	[*" $2 "*], [], ['  '], [ $1="$2"], [ $1="[$]$1 $2"])])
AC_DEFUN([RUBY_APPEND_OPTIONS],
	[# RUBY_APPEND_OPTIONS($1)
	for rb_opt in $2; do
	AS_CASE([" [$]{$1-} "],
	[*" [$]{rb_opt} "*], [], ['  '], [ $1="[$]{rb_opt}"], [ $1="[$]$1 [$]{rb_opt}"])
	done])
AC_DEFUN([RUBY_PREPEND_OPTION],
	[# RUBY_PREPEND_OPTION($1)
	AS_CASE([" [$]{$1-} "],
	[*" $2 "*], [], ['  '], [ $1="$2"], [ $1="$2 [$]$1"])])
AC_DEFUN([RUBY_PREPEND_OPTIONS],
	[# RUBY_PREPEND_OPTIONS($1)
	unset rb_opts; for rb_opt in $2; do
	AS_CASE([" [$]{rb_opts} [$]{$1-} "],
	[*" [$]{rb_opt} "*], [], ['  '], [ $1="[$]{rb_opt}"], [ rb_opts="[$]{rb_opts}[$]{rb_opt} "])
	done
	$1="[$]{rb_opts}[$]$1"])

AC_ARG_WITH(arch,
	AS_HELP_STRING([--with-arch=ARCHS],
		       [build an Apple/NeXT Multi Architecture Binary (MAB);
                          ARCHS is a comma-delimited list of architectures for
                          which to build; if this option is disabled or omitted
			  entirely, then the package will be built only for the
			  target platform]),
       [target_archs="$withval"], [unset target_archs])

AC_DEFUN([RUBY_DEFAULT_ARCH], [
AC_MSG_CHECKING([arch option])
AS_CASE([$1],
	[*64],        [ARCH_FLAG=-m64],
	[[i[3-6]86]], [ARCH_FLAG=-m32],
	[AC_MSG_ERROR(unknown target architecture: $target_archs)]
	)
AC_MSG_RESULT([$ARCH_FLAG])
])

AC_DEFUN([RUBY_UNIVERSAL_ARCH], [
# RUBY_UNIVERSAL_ARCH begin
ARCH_FLAG=`expr " $CXXFLAGS " : ['.* \(-m[0-9][0-9]*\) ']`
test ${CXXFLAGS+set} && CXXFLAGS=`echo "$CXXFLAGS" | sed [-e 's/ *-arch  *[^ ]*//g' -e 's/ *-m32//g' -e 's/ *-m64//g']`
ARCH_FLAG=`expr " $CFLAGS " : ['.* \(-m[0-9][0-9]*\) ']`
test ${CFLAGS+set} && CFLAGS=`echo "$CFLAGS" | sed [-e 's/ *-arch  *[^ ]*//g' -e 's/ *-m32//g' -e 's/ *-m64//g']`
test ${LDFLAGS+set} && LDFLAGS=`echo "$LDFLAGS" | sed [-e 's/ *-arch  *[^ ]*//g' -e 's/ *-m32//g' -e 's/ *-m64//g']`
unset universal_binary universal_archnames
if test ${target_archs+set}; then
    AC_MSG_CHECKING([target architectures])
    target_archs=`echo $target_archs | tr , ' '`
    # /usr/lib/arch_tool -archify_list $TARGET_ARCHS
    for archs in $target_archs
    do
	AS_CASE([",$universal_binary,"],[*",$archs,"*], [],[
	    cpu=`$SHELL "$ac_aux_dir/config.sub" "${archs}-${target_os}" 2>&1` || {
	        AC_MSG_RESULT([failed])
		AC_MSG_ERROR([$cpu])
	    }
	    cpu=`echo $cpu | sed 's/-.*-.*//'`
	    universal_binary="${universal_binary+$universal_binary,}$cpu"
	    universal_archnames="${universal_archnames} ${archs}=${cpu}"
	    ARCH_FLAG="${ARCH_FLAG+$ARCH_FLAG }-arch $archs"
	    ])
    done
    target_archs="$universal_binary"
    unset universal_binary
    AS_CASE(["$target_archs"],
      [*,*], [universal_binary=yes],
             [unset universal_archnames])
    AC_MSG_RESULT([$target_archs])

    target=`echo $target | sed "s/^$target_cpu-/-/"`
    target_alias=`echo $target_alias | sed "s/^$target_cpu-/-/"`
    if test "${universal_binary-no}" = yes; then
	AC_SUBST(try_header,try_compile)
	target_cpu=universal
	real_cross_compiling=$cross_compiling
    else
	if test x"$target_cpu" != x"${target_archs}"; then
	    echo 'int main(){return 0;}' > conftest.c
	    if $CC $CFLAGS $ARCH_FLAG -o conftest conftest.c > /dev/null 2>&1; then
		rm -fr conftest.*
	    else
		RUBY_DEFAULT_ARCH("$target_archs")
	    fi
	fi
	target_cpu=${target_archs}
    fi
    AS_CASE(["$target"], [-*], [ target="$target_cpu${target}"])
    AS_CASE(["$target_alias"], [-*], [ target_alias="$target_cpu${target_alias}"])
else
    if test x"$target_alias" = x; then
	AS_CASE(["$target_os"],
	  [darwin*], [
	    AC_MSG_CHECKING([for real target cpu])
	    target=`echo $target | sed "s/^$target_cpu-/-/"`
	    target_cpu=`$CC -E - 2>/dev/null <<EOF |
#ifdef __x86_64__
"processor-name=x86_64"
#endif
#ifdef __i386__
"processor-name=i386"
#endif
#ifdef __ppc__
"processor-name=powerpc"
#endif
#ifdef __ppc64__
"processor-name=powerpc64"
#endif
EOF
	    sed -n 's/^"processor-name=\(.*\)"/\1/p'`
	    target="$target_cpu${target}"
	    AC_MSG_RESULT([$target_cpu])
	    ])
    fi
    target_archs="$target_cpu"
fi
if test "${target_archs}" != "${rb_cv_target_archs-${target_archs}}"; then
    AC_MSG_ERROR([target arch(s) has changed from ${rb_cv_target_archs-nothing} to ${target_archs}])
else
    rb_cv_target_archs=${target_archs}
fi
if test "x${ARCH_FLAG}" != x; then
    CFLAGS="${CFLAGS:+$CFLAGS }${ARCH_FLAG}"
    LDFLAGS="${LDFLAGS:+$LDFLAGS }${ARCH_FLAG}"
fi
# RUBY_UNIVERSAL_ARCH end
])

AC_ARG_ENABLE(load-relative,
       AS_HELP_STRING([--enable-load-relative], [resolve load paths at run time]),
       [load_relative=$enableval])

AC_ARG_PROGRAM

dnl Checks for programs.

cflagspat=
test -z "$optflags" ||
    cflagspat="$cflagspat;s|"`eval echo '"'"${optflags}"'"' | sed 's/[[][|.*]]/\\&/g;s/^ */ /;s/ *$/ /'`'| |g'
test -z "$debugflags" ||
    cflagspat="$cflagspat;s|"`eval echo '"'"${debugflags}"'"' | sed 's/[[][|.*]]/\\&/g;s/^ */ /;s/ *$/ /'`'| |g'
test -z "warnflags" ||
    cflagspat="$cflagspat;s|"`eval echo '"'"${warnflags}"'"' | sed 's/[[][|.*]]/\\&/g;s/^ */ /;s/ *$/ /'`'| |g'
if test -z "${CFLAGS+set}"; then
    cflags=`echo " $cflags " | sed "$cflagspat;s/^ *//;s/ *$//"`
    orig_cflags="$cflags"
    cflags="$cflags "'${optflags} ${debugflags} ${warnflags}'
fi
if test -z "${CXXFLAGS+set}"; then
    cxxflags=`echo " $cxxflags " | sed "$cflagspat;s/^ *//;s/ *$//"`
    orig_cxxflags="$cxxflags"
    cxxflags="$cxxflags "'${optflags} ${debugflags} ${warnflags}'
fi

RUBY_NACL
AS_CASE(["$host_os:$build_os"],
[darwin*:darwin*], [
    AC_CHECK_TOOLS(CC, [clang gcc cc])
    # Following Apple deployed clang are broken
    # clang version 1.0 (http://llvm.org/svn/llvm-project/cfe/tags/Apple/clang-23 exported)
    # Apple clang version 2.0 (tags/Apple/clang-137) (based on LLVM 2.9svn)
    # Apple clang version 2.1 (tags/Apple/clang-163.7.1) (based on LLVM 3.0svn)
    if ! $CC -E -xc - <<SRC >/dev/null; then
	@%:@if defined __APPLE_CC__ && defined __clang_major__ && __clang_major__ < 3
	@%:@error premature clang
	@%:@endif
SRC
	AC_MSG_ERROR([clang version 3.0 or later is required])
    fi
])
if test x"${build}" != x"${host}"; then
  AC_CHECK_TOOL(CC, gcc)
fi

AC_PROG_CC

dnl Select the appropriate C++ compiler in OS X
AS_CASE(["$build_os"],
  [darwin1*.*], [
    AS_CASE(["x$CC"],
      [xgcc-4.2|x/usr/bin/gcc-4.2], [: ${CXX=g++-4.2}],
      [xgcc|x/usr/bin/gcc],         [: ${CXX=g++}],
      [xcc|x/usr/bin/cc],           [: ${CXX=c++}],
      [xicc],                       [: ${CXX=icpc}],
      [xclang|x/usr/bin/clang],     [: ${CXX=clang++}])
  ])
test -z "$CXX" || ac_cv_prog_CXX="$CXX"

AC_PROG_CXX
RUBY_MINGW32
AC_PROG_GCC_TRADITIONAL
AC_SUBST(GCC)
AS_CASE(["$target_os"],
[solaris*], [AC_PATH_TOOL([LD], [ld], [/usr/ccs/bin/ld], [/usr/ccs/bin:$PATH])],
[AC_CHECK_TOOL([LD], [ld], [ld])])
AC_SUBST(LD)
if test "$GCC" = yes; then
    linker_flag=-Wl,
    : ${optflags=-O3}
    gcc_major=`echo =__GNUC__ | $CC -E -xc - | sed '/^=/!d;s///'`
    gcc_minor=`echo =__GNUC_MINOR__ | $CC -E -xc - | sed '/^=/!d;s///'`
    test -n "$gcc_major" || gcc_major=0
    test -n "$gcc_minor" || gcc_minor=0
    # RUBY_APPEND_OPTIONS(XCFLAGS, ["-include ruby/config.h" "-include ruby/missing.h"])
else
    linker_flag=
fi

RUBY_PROG_GNU_LD
RUBY_CPPOUTFILE

: ${OUTFLAG='-o '}
: ${COUTFLAG=${OUTFLAG}}
: ${CSRCFLAG=''}
AC_SUBST(OUTFLAG)
AC_SUBST(COUTFLAG)
AC_SUBST(CSRCFLAG)

cc_version=
for option in --version -v -V -qversion; do
    cc_version_message=`$CC $option 2>&1`
    cc_version_status=$?
    AS_CASE($cc_version_status, [0], [:], [continue])
    AS_CASE($cc_version_message, [*Warning*], [continue])
    cc_version='$(CC) '$option
    break
done
AC_SUBST(CC_VERSION, $cc_version)
AC_SUBST(CC_VERSION_MESSAGE, $cc_version_message)

RUBY_UNIVERSAL_ARCH
if test "$target_cpu" != "$host_cpu" -a "$GCC" = yes -a "$cross_compiling" = no -a "$universal_binary" = no; then
    RUBY_DEFAULT_ARCH("$target_cpu")
fi

AS_CASE(["$target_cpu-$target_os"], [[i[3-6]86*]], [
	 AC_CACHE_CHECK([for __sync_val_compare_and_swap], [rb_cv_gcc_compiler_cas], [
			 AC_TRY_LINK([unsigned long atomic_var;],
				     [
				      __sync_val_compare_and_swap(&atomic_var, 0, 1);
				      ],
				      [rb_cv_gcc_compiler_cas=yes],
				      [rb_cv_gcc_compiler_cas=no])])
	 if test "$rb_cv_gcc_compiler_cas" = no; then
		 unset rb_cv_gcc_compiler_cas
		 save_CFLAGS="$CFLAGS"
		 CFLAGS="$CFLAGS -march=i486"
		 AC_CACHE_CHECK([for __sync_val_compare_and_swap with -march=i486], [rb_cv_gcc_compiler_cas], [
				 AC_TRY_LINK([unsigned long atomic_var;],
					     [
					      __sync_val_compare_and_swap(&atomic_var, 0, 1);
					      ],
					      [rb_cv_gcc_compiler_cas=yes
					       ARCH_FLAG="-march=i486"],
					      [rb_cv_gcc_compiler_cas=no])])
		 CFLAGS="$save_CFLAGS"
	 fi])

AS_CASE(["$target_os"], [darwin*], [
if libtool 2>&1 | grep no_warning_for_no_symbols > /dev/null; then
  ac_cv_prog_ac_ct_RANLIB=:
  ac_cv_prog_ac_ct_AR='libtool -static'
  rb_cv_arflags='-no_warning_for_no_symbols -o'
fi
])
AC_CHECK_TOOL(RANLIB, ranlib, :)
AC_CHECK_TOOL(AR, ar)
if test -z "$AR"; then
  AC_CHECK_PROGS(AR, aal, ar)
fi
AC_CACHE_CHECK([for $AR flags], [rb_cv_arflags], [
    AS_IF([$AR rcD conftest.a > /dev/null 2>&1 && rm conftest.a],
	[rb_cv_arflags=rcD], [rb_cv_arflags=rcu])
])
AC_SUBST(ARFLAGS, ["$rb_cv_arflags "])

AC_CHECK_TOOL(AS, as)
ASFLAGS=$ASFLAGS
AC_SUBST(ASFLAGS)

AS_CASE(["$target_os"],[cygwin*|mingw*], [ac_cv_prog_ac_ct_OBJCOPY=":"])

# BSD's ports and MacPorts prefix GNU binutils with 'g'
AC_CHECK_TOOLS(OBJDUMP, [objdump gobjdump])
AC_CHECK_TOOLS(OBJCOPY, [objcopy gobjcopy])

AS_CASE(["$target_os"],
[cygwin*|mingw*], [
    AC_CHECK_TOOL(WINDRES, windres)
    AC_CHECK_TOOL(DLLWRAP, dllwrap)
    target=`echo $target | sed "s/^$target_cpu-/-/"`
    target_alias=`echo $target_alias | sed "s/^$target_cpu-/-/"`
    target_cpu=`echo $target_cpu | sed s/i.86/i386/`
    AS_CASE(["$target"], [-*], [ target="$target_cpu${target}"])
    AS_CASE(["$target_alias"], [-*], [ target_alias="$target_cpu${target_alias}"])
    AS_CASE(["$target_os"],
    [mingw*], [
	test "$rb_cv_msvcrt" = "" && unset rb_cv_msvcrt
	AC_CACHE_CHECK(for mingw32 runtime DLL, rb_cv_msvcrt, [
	AC_TRY_LINK([@%:@include <stdio.h>],
		    [FILE* volatile f = stdin; return 0;],
		    [rb_cv_msvcrt=`$OBJDUMP -p conftest$ac_exeext |
				   tr A-Z a-z |
				   sed -n '/^[[ 	]]*dll name: \(msvc.*\)\.dll$/{s//\1/p;q;}'`],
		    [rb_cv_msvcrt=msvcrt])
	test "$rb_cv_msvcrt" = "" && rb_cv_msvcrt=msvcrt])
	RT_VER=`echo "$rb_cv_msvcrt" | tr -cd [0-9]`
	test "$RT_VER" = "" && RT_VER=60
	AC_DEFINE_UNQUOTED(RUBY_MSVCRT_VERSION, $RT_VER)
    ])
    : ${enable_shared=yes}
    ],
[aix*],     [AC_CHECK_TOOL(NM, nm, /usr/ccs/bin/nm, /usr/ccs/bin:$PATH)],
[hiuxmpp*], [AC_DEFINE(__HIUX_MPP__)])    # by TOYODA Eizi <toyoda@npd.kishou.go.jp>
AC_CHECK_TOOL(NM, nm)

AC_PROG_LN_S
AC_PROG_MAKE_SET
AC_PROG_INSTALL
AC_PROG_MKDIR_P
if test "x$MKDIR_P" = "x -d"; then
  if test x"$as_mkdir_p" != xfalse; then
    MKDIR_P='mkdir -p'
    echo "use 'mkdir -p' as MKDIR_P"
  else
    AC_MSG_ERROR([mkdir -p is required])
  fi
fi
MAKEDIRS="$MKDIR_P"
AC_SUBST(MAKEDIRS)

AC_DEFUN([RUBY_DTRACE_AVAILABLE],
[AC_CACHE_CHECK(whether dtrace USDT is available, rb_cv_dtrace_available,
[
    echo "provider conftest{ probe fire(); };" > conftest_provider.d
    rb_cv_dtrace_available=no
    AS_FOR(opt, rb_dtrace_opt, ["-xnolibs" ""], [dnl
	AS_IF([$DTRACE opt -h -o conftest_provider.h -s conftest_provider.d >/dev/null 2>/dev/null],
	    [], [continue])
	AC_TRY_COMPILE([@%:@include "conftest_provider.h"], [CONFTEST_FIRE();],
	    [], [continue])
	# DTrace is available on the system
	rb_cv_dtrace_available=yes${rb_dtrace_opt:+"(opt)"}
	break
    ])
    rm -f conftest.[co] conftest_provider.[dho]
])
AS_CASE(["$rb_cv_dtrace_available"], ["yes("*")"],
    [DTRACE_OPT=`expr "$rb_cv_dtrace_available" : "yes(\(.*\))"`])
])

AC_DEFUN([RUBY_DTRACE_POSTPROCESS],
[AC_CACHE_CHECK(whether $DTRACE needs post processing, rb_cv_prog_dtrace_g,
[
  rb_cv_prog_dtrace_g=no
  if {
    cat >conftest_provider.d <<_PROBES &&
    provider conftest {
      probe fire();
    };
_PROBES
    $DTRACE ${DTRACE_OPT} -h -o conftest_provider.h -s conftest_provider.d >/dev/null 2>/dev/null &&
    :
  }; then
    AC_TRY_COMPILE([@%:@include "conftest_provider.h"], [CONFTEST_FIRE();], [
	if {
	    cp -p conftest.${ac_objext} conftest.${ac_objext}.save &&
	    $DTRACE ${DTRACE_OPT} -G -s conftest_provider.d conftest.${ac_objext} 2>/dev/null &&
	    :
	}; then
	    if cmp -s conftest.o conftest.${ac_objext}.save; then
		rb_cv_prog_dtrace_g=yes
	    else
		rb_cv_prog_dtrace_g=rebuild
	    fi
	fi])
  fi
  rm -f conftest.[co] conftest_provider.[dho]
])
])

AC_CHECK_PROG([DTRACE], [${ac_tool_prefix}dtrace], [${ac_tool_prefix}dtrace])
if test "$cross_compiling:$ac_cv_prog_DTRACE" = no: -a -n "$ac_tool_prefix"; then
    AC_CHECK_PROG([DTRACE], [dtrace], [dtrace])
fi

AC_CHECK_PROGS(DOT, dot)
AC_CHECK_PROGS(DOXYGEN, doxygen)
AS_CASE(["${host_os}"], [nacl], [AC_PATH_PROG(PYTHON, python)])

AC_CHECK_PROG(PKG_CONFIG, pkg-config, [pkg-config], [], [],
    [`"$as_dir/$ac_word$ac_exec_ext" --print-errors --version > /dev/null 2>&1 || echo "$as_dir/$ac_word$ac_exec_ext"`])

# checks for UNIX variants that set C preprocessor variables
AC_USE_SYSTEM_EXTENSIONS

AC_SUBST(RM, ['rm -f'])
AC_SUBST(CP, ['cp'])
RMDIRS='$(top_srcdir)/tool/rmdirs'
RMDIR=rmdir
mkdir "rmdirs_$$_test" "rmdirs_$$_test/a"
rmdir --ignore-fail-on-non-empty "rmdirs_$$_test" 2>/dev/null &&
RMDIR='rmdir --ignore-fail-on-non-empty'
$RMDIR -p "rmdirs_$$_test/a" 2>/dev/null &&
{ test -d "rmdirs_$$_test" || RMDIRS="$RMDIR -p"; }
rmdir "rmdirs_$$_test/a" "rmdirs_$$_test" 2>/dev/null
AC_SUBST(RMDIR)
AC_SUBST(RMDIRS)
AC_SUBST(RMALL, ['rm -fr'])

AC_MSG_CHECKING([for cd using physical directory])
rm -fr conf$$.dir
mkdir conf$$.dir &&
(cd conf$$.dir && mkdir src build && cd src &&
$as_ln_s ../build . > /dev/null 2>&1 && cd build &&
for chdir in 'cd -P' 'PWD= cd'; do
    /bin/sh -c "$chdir ../src && echo '$chdir' > cdcmd" 2> /dev/null && break
done)
if test -f conf$$.dir/src/cdcmd; then
    read CHDIR < conf$$.dir/src/cdcmd 2> /dev/null
else
    CHDIR=cd
fi
rm -fr conf$$.dir
AC_MSG_RESULT([$CHDIR])
AC_SUBST(CHDIR)

}
{ # compiler section

AC_DEFUN([RUBY_WERROR_FLAG], [dnl
save_CFLAGS="$CFLAGS"
CFLAGS="$CFLAGS $rb_cv_warnflags"
if test "${ac_c_werror_flag+set}"; then
  rb_c_werror_flag="$ac_c_werror_flag"
else
  unset rb_c_werror_flag
fi
ac_c_werror_flag=yes
$1
CFLAGS="$save_CFLAGS"
save_CFLAGS=
if test "${rb_c_werror_flag+set}"; then
  ac_c_werror_flag="$rb_c_werror_flag"
else
  unset ac_c_werror_flag
fi])

RUBY_WERROR_FLAG([
    AC_MSG_CHECKING([whether CFLAGS is valid])
    AC_TRY_COMPILE([], [],
	[AC_MSG_RESULT(yes)],
	[
	AC_MSG_RESULT(no)
	AC_MSG_ERROR([something wrong with CFLAGS="$CFLAGS"])
	]
    )
    AC_MSG_CHECKING([whether LDFLAGS is valid])
    {
	mkdir tmp.$$.try_link &&
	cd tmp.$$.try_link &&
	cp ../confdefs.h . &&
	echo '<?xml?><plist><dict><key>CFBundleIdentifier</key><string></string></dict></plist>' > Info.plist &&
	:
    } || AC_MSG_ERROR([failed to make temporary directory])
    AC_TRY_LINK([], [],
	[AC_MSG_RESULT(yes)],
	[
	cd .. && rm -fr tmp.$$.try_link
	AC_MSG_RESULT(no)
	AC_MSG_ERROR([something wrong with LDFLAGS="$LDFLAGS"])
	]
    )
    cd .. && rm -fr tmp.$$.try_link
])

AC_DEFUN([RUBY_TRY_CFLAGS], [
    AC_MSG_CHECKING([whether ]$1[ is accepted as CFLAGS])
    RUBY_WERROR_FLAG([
    CFLAGS="[$]CFLAGS $1"
    AC_TRY_COMPILE([$4], [$5],
	[$2
	AC_MSG_RESULT(yes)],
	[$3
	AC_MSG_RESULT(no)])
    ])
])

AC_DEFUN([RUBY_TRY_LDFLAGS], [
    save_LDFLAGS="$LDFLAGS"
    LDFLAGS="[$]LDFLAGS $1"
    AC_MSG_CHECKING([whether $1 is accepted as LDFLAGS])
    RUBY_WERROR_FLAG([
    AC_TRY_LINK([$4], [$5],
	[$2
	AC_MSG_RESULT(yes)],
	[$3
	AC_MSG_RESULT(no)])
    ])
    LDFLAGS="$save_LDFLAGS"
    save_LDFLAGS=
])

: ${DLDFLAGS="$LDFLAGS"}
: ${RPATHFLAG=''}
rpathflag=''
AS_IF([test x"${RPATHFLAG}" = x], [
    AS_CASE(["$target_os"],
	[hpux*], [AS_IF([test "$rb_cv_prog_gnu_ld" = no], [rpathflag='+b '])],
	[aix*], [rpathflag='-blibpath:'],
	[for rpathflag in -R "-rpath "; do
	    AS_CASE("$rpathflag",
		    [*" "], [AS_CASE(["${linker_flag}"],
				     [*,], [rpathflag=`echo "$rpathflag" | tr ' ' ,`])])
	    rpathflag="${linker_flag}${rpathflag}"
	    RUBY_TRY_LDFLAGS([${rpathflag}.], [], [rpathflag=])
	    AS_IF([test "x${rpathflag}" != x], [])
        done])
], [
    rpathflag=`echo "$RPATHFLAG" | sed 's/%.*//'`
])

AS_CASE([$RUBY_PATCHLEVEL], [-*],
	[particular_werror_flags=yes], [particular_werror_flags=no])
AC_ARG_ENABLE(werror,
	AS_HELP_STRING([--disable-werror],
		       [don't make warnings into errors
		       even if a compiler support -Werror feature
		       [[disabled by default unless development version]]]),
	[particular_werror_flags=$enableval])

rb_cv_warnflags="$warnflags"
if test "$GCC:${warnflags+set}:no" = yes::no; then
    if test $gcc_major -ge 4; then
	extra_warning=-Werror=extra-tokens
    else
	extra_warning=
    fi
    if test $gcc_major -ge 5 -a $gcc_major -le 6; then
	extra_warning="$extra_warning -Wno-maybe-uninitialized"
    fi
    for wflag in -Wno-unused-parameter -Wno-parentheses -Wno-long-long \
                 -diag-disable=2259 \
		 -Wno-missing-field-initializers \
		 -Wno-tautological-compare \
		 -Wno-parentheses-equality \
		 -Wno-constant-logical-operand \
		 -Wno-self-assign \
		 -Wunused-variable \
		 -Werror=implicit-int \
		 -Werror=pointer-arith \
		 -Werror=write-strings \
		 -Werror=declaration-after-statement \
		 -Werror=shorten-64-to-32 \
		 -Werror=implicit-function-declaration \
		 -Werror=division-by-zero \
		 -Werror=deprecated-declarations \
		 -Wno-packed-bitfield-compat \
		 -Wsuggest-attribute=noreturn \
		 -Wsuggest-attribute=format \
		 -Wimplicit-fallthrough=0 \
		 $extra_warning \
		 ; do
	if test "$particular_werror_flags" != yes; then
	    wflag=`echo x$wflag | sed 's/^x-Werror=/-W/;s/^x//'`
	fi
	ok=no
	RUBY_TRY_CFLAGS($wflag, [
	    RUBY_APPEND_OPTIONS(warnflags, $wflag)
	    ok=yes
	])
	AS_CASE([$ok:$wflag], [no:-Werror=*], [
	    wflag=`echo x$wflag | sed 's/^x-Werror=/-W/'`
	    RUBY_TRY_CFLAGS($wflag, [
		RUBY_APPEND_OPTIONS(warnflags, $wflag)
		particular_werror_flags=no
	    ])
	])
    done
    AS_CASE([" $warnflags "],[*" -Wno-missing-field-initializers "*], [wflag="-Wall -Wextra"],
                             [wflag=-Wall])
    RUBY_TRY_CFLAGS($wflag, [warnflags="$wflag${warnflags+ $warnflags}"])
    # Disable warnflags while conftest. -Werror=* flags might make bad OS capability guess.
    rb_cv_warnflags="$warnflags"
    warnflags=
fi
RUBY_TRY_CFLAGS(-Qunused-arguments, [RUBY_APPEND_OPTIONS(rb_cv_wsuppress_flags, -Qunused-arguments)])

for n in infinity nan; do
    m=AS_TR_CPP($n)
    AC_CACHE_CHECK([whether $m is available without C99 option], rb_cv_$n,
	[AC_COMPILE_IFELSE(
	    [AC_LANG_BOOL_COMPILE_TRY(AC_INCLUDES_DEFAULT([@%:@include <math.h>
@%:@ifndef $m
@%:@error no $m
@%:@endif
]), [1])], [eval rb_cv_$n=yes], [eval rb_cv_$n=no])])
    if eval test '"$rb_cv_'$n'"' = yes; then
	AC_DEFINE_UNQUOTED([HAVE_]$m)
    fi
done

AC_ARG_WITH(compress-debug-sections,
	AS_HELP_STRING([--with-compress-debug-sections=type],
	    [enable debug section compression]),
	[compress_debug_sections=$withval], [compress_debug_sections=])

if test "$GCC" = yes; then
    # NaCl's glibc build generates undefined references to __memset_chk.
    # TODO(sbc): Remove this once NaCl's glibc is fixed.
    AS_CASE(["$target_os"], [nacl], [], [
      # -D_FORTIFY_SOURCE
      # When defined _FORTIFY_SOURCE, glibc enables some additional sanity
      # argument check. The performance drop is very little and Ubuntu enables
      # _FORTIFY_SOURCE=2 by default. So, let's support it for protecting us from
      # a mistake of silly C extensions.
      RUBY_TRY_CFLAGS(-D_FORTIFY_SOURCE=2, [RUBY_APPEND_OPTION(XCFLAGS, -D_FORTIFY_SOURCE=2)])
   ])

    # -fstack-protector
    AS_CASE(["$target_os"],
    [mingw*|nacl], [
	stack_protector=no
    ])
    if test -z "${stack_protector+set}"; then
	RUBY_TRY_CFLAGS(-fstack-protector, [stack_protector=yes], [stack_protector=no])
	if test "x$stack_protector" = xyes; then
	    RUBY_TRY_LDFLAGS(-fstack-protector, [], [stack_protector=broken])
	fi
    fi
    if test "x$stack_protector" = xyes; then
	RUBY_APPEND_OPTION(XCFLAGS, -fstack-protector)
	RUBY_APPEND_OPTION(XLDFLAGS, -fstack-protector)
	RUBY_APPEND_OPTION(LDFLAGS, -fstack-protector)
    fi

    AS_CASE("${compress_debug_sections:-zlib}",
    [none|no], [], [
    RUBY_TRY_LDFLAGS(${linker_flag}--compress-debug-sections=${compress_debug_sections:-zlib},
		     [compress_debug_sections=${compress_debug_sections:-zlib}],
		     [compress_debug_sections=no])
    ])
    if test "x$compress_debug_sections" != xno; then
	RUBY_APPEND_OPTION(DLDFLAGS, ${linker_flag}--compress-debug-sections=$compress_debug_sections)
    fi

    AS_CASE(["$target_os"],[mingw*], [
      # On  Windows  platforms,   system  provided  headers  are  VC++
      # optimized.  That  is, C++  habits are often  contaminated into
      # various  headers.  Most frequent  situation is  the use  of //
      # comments.   We  bypass  ANSI   C  mode  for  them.   Otherwise
      # extension libs cannot include those headers.

      # Since math.h in some mingw64 wrongly delcares frexp and modf
      # to be pure, the variables pointed by the second arguments are
      # considered uninitialized unexpectedly.
      AC_CACHE_CHECK([whether frexp and modf are broken],
	rb_cv_mingw64_broken_frexp_modf,
	[
	  save_CFLAGS="$CFLAGS"
	  if test "$particular_werror_flags" = "yes"; then
	    CFLAGS="$CFLAGS -Werror=uninitialized"
	  else
	    CFLAGS="$CFLAGS -Werror -Wuninitialized"
	  fi
	  AC_TRY_COMPILE([@%:@include <math.h>
	    int foo(double x)
	    {
	      int exp;
	      frexp(x, &exp);
	      return exp;
	    }], [if (foo(0.0)) return 1;],
	    [rb_cv_mingw64_broken_frexp_modf=no],
	    [rb_cv_mingw64_broken_frexp_modf=yes])
	  CFLAGS="$save_CFLAGS"
	])
      if test "$rb_cv_mingw64_broken_frexp_modf" = yes; then
	AC_DEFINE(RUBY_MINGW64_BROKEN_FREXP_MODF)
      fi
    ],
    [cygwin*|darwin*|netbsd*|nacl], [
      # need lgamma_r(), finite()
    ],
    [
      # ANSI (no XCFLAGS because this is C only)
	for ansi_options in -std=gnu99; do
	    RUBY_TRY_CFLAGS(${ansi_options}, [
		RUBY_APPEND_OPTIONS(warnflags, ${ansi_options})
		RUBY_APPEND_OPTIONS(strict_warnflags, ${ansi_options})
	    ], [ansi_options=])
	    test "x${ansi_options}" = x || break
	done
    ])

    # suppress annoying -Wstrict-overflow warnings
    RUBY_TRY_CFLAGS(-fno-strict-overflow, [RUBY_APPEND_OPTION(XCFLAGS, -fno-strict-overflow)])

    test "${debugflags+set}" || {RUBY_TRY_CFLAGS(-ggdb3, [debugflags=-ggdb3])}
    test "${debugflags+set}" || {RUBY_TRY_CFLAGS(-ggdb, [debugflags=-ggdb])}
    test "${debugflags+set}" || {RUBY_TRY_CFLAGS(-g3, [debugflags=-g3])}
fi
test $ac_cv_prog_cc_g = yes && : ${debugflags=-g}

if test "$GCC" = ""; then
    AS_CASE(["$target_os"],[aix*],[warnflags="$warnflags -qinfo=por" rb_cv_warnflags="$rb_cv_warnflags -qinfo=por"])
fi
if test "$GCC" = yes; then
    if test "$gcc_major" -ge 4; then
	RUBY_TRY_CFLAGS(-fvisibility=hidden, [visibility_option=yes], [visibility_option=no])
    fi
    AC_SUBST(WERRORFLAG, "-Werror")
    if test "$visibility_option" = yes; then
	RUBY_APPEND_OPTION(XCFLAGS, -fvisibility=hidden)
	AC_DEFINE(RUBY_SYMBOL_EXPORT_BEGIN, [_Pragma("GCC visibility push(default)")])
	AC_DEFINE(RUBY_SYMBOL_EXPORT_END,   [_Pragma("GCC visibility pop")])
    else
	RUBY_TRY_LDFLAGS([-Wl,-unexported_symbol,_Init_*], [visibility_option=ld], [visibility_option=no])
    fi
    test "$visibility_option" = no -o "$host_os" = nacl || OBJCOPY=:
fi

if test "$GCC" = yes; then
    # optflags

    AS_CASE(["$target_os"], [mingw*], [
	RUBY_TRY_CFLAGS(-fno-omit-frame-pointer, [optflags="${optflags+$optflags }-fno-omit-frame-pointer"])
	RUBY_TRY_CFLAGS(-static-libgcc, [static_libgcc=yes], [static_libgcc=no])
	if test "$static_libgcc" = yes; then
	    RUBY_APPEND_OPTION(EXTLDFLAGS, -static-libgcc)
	fi
    ])

    # disable fast-math
    for oflag in -fno-fast-math; do
	RUBY_TRY_CFLAGS($oflag, [RUBY_APPEND_OPTION(optflags, $oflag)])
    done
    for oflag in -fexcess-precision=standard -fp-model\ precise; do
	RUBY_TRY_CFLAGS($oflag, [RUBY_APPEND_OPTION(XCFLAGS, $oflag)])
    done
fi

AC_ARG_WITH(opt-dir,
	AS_HELP_STRING([--with-opt-dir=DIR-LIST],
		       [add optional headers and libraries directories separated by $PATH_SEPARATOR]),
	[
		val=`echo "$PATH_SEPARATOR$withval" | sed "s|$PATH_SEPARATOR\([[^$PATH_SEPARATOR]*]\)| -I\1/include|g;s/^ //"`
		CPPFLAGS="$CPPFLAGS $val"
		val=`echo "$PATH_SEPARATOR$withval" | sed "s|$PATH_SEPARATOR\([[^$PATH_SEPARATOR]*]\)| -L\1/lib${rpathflag:+ $rpathflag\\\\1/lib}|g;s/^ //"`
		LDFLAGS="$LDFLAGS $val"
		LDFLAGS_OPTDIR="$val"
		OPT_DIR="$withval"
	], [OPT_DIR=])

test -z "${ac_env_CFLAGS_set}" -a -n "${cflags+set}" && eval CFLAGS="\"$cflags $ARCH_FLAG\""
test -z "${ac_env_CXXFLAGS_set}" -a -n "${cxxflags+set}" && eval CXXFLAGS="\"$cxxflags $ARCH_FLAG\""

}
{ # header and library section

AC_ARG_WITH(winnt-ver,
  AS_HELP_STRING([--with-winnt-ver=0xXXXX], [target Windows NT version (default to 0x0501)]),
  [with_winnt_ver="$withval"], [with_winnt_ver="0x0501"])
AS_CASE(["$target_os"],
[mingw*], [
  RUBY_APPEND_OPTION(CPPFLAGS, -D_WIN32_WINNT=$with_winnt_ver)
  RUBY_APPEND_OPTION(CPPFLAGS, -D__MINGW_USE_VC2005_COMPAT)
])

AS_CASE(["$target_os"],
[freebsd*], [
  AC_CACHE_CHECK([whether pthread should be enabled by default],
    rb_cv_enable_pthread_default,
    [AC_TRY_CPP([
#include <osreldate.h>
#if __FreeBSD_version < 502102
#error pthread should be disabled on this platform
#endif
      ],
      rb_cv_enable_pthread_default=yes,
      rb_cv_enable_pthread_default=no)])
  enable_pthread=$rb_cv_enable_pthread_default
  ],
[mingw*], [
  enable_pthread=no
  ],
[
  enable_pthread=yes
  ])

AC_ARG_ENABLE(pthread,
       AS_HELP_STRING([--enable-pthread], [obsolete, and ignored]))

dnl Checks for libraries.
AS_CASE(["$target_os"],[*bsd*|dragonfly*],[],[ac_cv_func_daemon=no])

POSTLINK=:
AC_SUBST(POSTLINK)
AS_CASE(["$target_os"],
[nextstep*], [	],
[openstep*], [	],
[rhapsody*], [	],
[darwin*], [	RUBY_PREPEND_OPTION(LIBS, -lobjc)
		RUBY_APPEND_OPTIONS(CPPFLAGS, -D_XOPEN_SOURCE -D_DARWIN_C_SOURCE -D_DARWIN_UNLIMITED_SELECT -D_REENTRANT)
		AC_MSG_CHECKING(whether Mac OS X 10.5 or later)
		AC_TRY_CPP([#include <AvailabilityMacros.h>
		    #if MAC_OS_X_VERSION_MAX_ALLOWED <= 1040
		    #error pre OS X 10.4
		    [!<===== pre OS X 10.4 =====>]
		    #endif
		    ],
		    [macosx_10_5=yes], [macosx_10_5=no])
		AC_MSG_RESULT($macosx_10_5)
		AS_IF([test "${target_os@%:@darwin}" -ge 16], [
		    ac_cv_func___syscall=no
		    ac_cv_func_syscall=no
		    ac_cv_header_sys_syscall_h=no
		    ac_cv_header_syscall_h=no
		])
		if test $macosx_10_5 = yes; then
		    ac_cv_func_getcontext=no
		    ac_cv_func_setcontext=no
		else
		    AC_DEFINE(BROKEN_SETREUID, 1)
		    AC_DEFINE(BROKEN_SETREGID, 1)
		fi
		incs=`$CC -v -E -xc - < /dev/null 2>&1 | sed ['1,/^@%:@include </d;s/^ *//;s|[^./][^/]*/\.\./||g;/\/include$/!d;s||/lib|;/\/usr\/lib/d']`
		for d in `$CC -print-search-dirs | sed -e '/^libraries: */!d;s///' | tr : '\012' | fgrep -v /../ | sed -n 's|^\(/.*/lib\)/$|\1|p'`; do
		    incs=`echo "$incs" | fgrep -v "$d"`
		done
		for d in $incs; do
		    test -d "$d" && RUBY_APPEND_OPTIONS(LDFLAGS, "-L$d")
		done
		ac_cv_type_getgroups=gid_t # getgroups() on Rosetta fills garbage
		ac_cv_lib_crypt_crypt=no
		ac_cv_func_fdatasync=no # Mac OS X wrongly reports it has fdatasync()
		ac_cv_func_vfork=no
		if test $gcc_major -lt 4 -o \( $gcc_major -eq 4 -a $gcc_minor -lt 3 \); then
		    ac_cv_func___builtin_setjmp=no
		fi
		AC_CACHE_CHECK(for broken crypt with 8bit chars, rb_cv_broken_crypt,
		    [AC_TRY_RUN([
#include <stdio.h>
#include <unistd.h>
#include <string.h>

void
broken_crypt(const char *salt, const char *buf1, const char *buf2)
{
#if 0
    printf("%.2x%.2x: %s -> %s\n", (unsigned char)salt[0], (unsigned char)salt[1],
	   buf1+2, buf2+2);
#endif
}

int
main()
{
    int i;
    char salt[2], buf[256], *s;
    for (i = 0; i < 128*128; i++) {
	salt[0] = 0x80 | (i & 0x7f);
	salt[1] = 0x80 | (i >> 7);
	strcpy(buf, crypt("", salt));
	if (strcmp(buf, s = crypt("", salt))) {
	    broken_crypt(salt, buf, s);
	    return 1;
	}
    }
    salt[0] = salt[1] = ' ';
    strcpy(buf, crypt("", salt));
    salt[0] = salt[1] = 0x80 | ' ';
    if (strcmp(buf, s = crypt("", salt))) {
	broken_crypt(salt, buf, s);
	return 1;
    }
    return 0;
}
],
		    rb_cv_broken_crypt=no,
		    rb_cv_broken_crypt=yes,
		    rb_cv_broken_crypt=yes)])
		if test "$rb_cv_broken_crypt" = yes; then
		   AC_DEFINE(BROKEN_CRYPT, 1)
		fi
		AC_CHECK_PROGS(codesign, codesign)
		if test -n "$codesign"; then
		    POSTLINK="test -z '\$(RUBY_CODESIGN)' || $codesign -s '\$(RUBY_CODESIGN)' -f \$@"
		    LINK_SO="$LINK_SO
\$(POSTLINK)"
		fi
		AC_CHECK_HEADERS(crt_externs.h, [], [], [
		    #include <crt_externs.h>
		])
		],
[hpux*], [	LIBS="-lm $LIBS"
		ac_cv_c_inline=no],
[solaris*], [	LIBS="-lm $LIBS"
		ac_cv_func_vfork=no
		AC_MSG_CHECKING(whether _XOPEN_SOURCE is already given)
		AC_TRY_COMPILE([#include <unistd.h>
		    #ifndef _XOPEN_SOURCE
		    #error _XOPEN_SOURCE is not defined
		    #endif
		    ], [],
		    [given_xopen_source=yes], [given_xopen_source=no])
		AC_MSG_RESULT($given_xopen_source)
		if test $given_xopen_source = no; then
		  # On Solaris, with gcc, -std=iso9899:1999 in $ansi_options
		  # is often also needed in CPPFLAGS, because some feature
		  # definitions vary depending on such standards options.
		  AS_CASE(["${ansi_options}"],
		  [*-std=iso9899:1999*], [
		    RUBY_APPEND_OPTIONS(CPPFLAGS, ${ansi_options})
		  ])
		  AC_MSG_CHECKING(appropriate _XOPEN_SOURCE value to define)
		  define_xopen_source=""
		  for tmp_xpg in 7 6 5; do
		    if test x"$define_xopen_source" != x; then
		        break
		    fi
		    # Both AC_TRY_CPP and AC_TRY_COMPILE should pass
		    # because some options may not be set to CPPFLAGS.
		    AC_TRY_CPP([
			#define _XOPEN_SOURCE ${tmp_xpg}00
			#include <unistd.h>
			#ifndef _XPG${tmp_xpg}
			#error _XPG${tmp_xpg} should be defined by _XOPEN_SOURCE=${tmp_xpg}00
			#endif
			], [
			AC_TRY_COMPILE([
			#define _XOPEN_SOURCE ${tmp_xpg}00
			#include <unistd.h>
			#ifndef _XPG${tmp_xpg}
			#error _XPG${tmp_xpg} should be defined by _XOPEN_SOURCE=${tmp_xpg}00
			#endif
			], [],
			[define_xopen_source=${tmp_xpg}00], [])
			], [])
		  done
		  if test x"$define_xopen_source" = x; then
		    define_xopen_source=no
		  fi
		  AC_MSG_RESULT($define_xopen_source)
		  if test x"$define_xopen_source" != xno; then
		    RUBY_APPEND_OPTIONS(CPPFLAGS, -D_XOPEN_SOURCE=$define_xopen_source)
		  fi
		fi
		],
[haiku*], [
		LIBS="$LIBS" # m lib is include in root
		],
[cygwin*], [	ac_cv_header_langinfo_h=yes
		RUBY_APPEND_OPTIONS(CPPFLAGS, -D_XOPEN_SOURCE -D_GNU_SOURCE)
		AC_CHECK_FUNCS(cygwin_conv_path)
		AC_LIBOBJ([langinfo])
		],
[mingw*], [	LIBS="-lshell32 -lws2_32 -liphlpapi -limagehlp -lshlwapi $LIBS"
		ac_cv_header_a_out_h=no
		ac_cv_header_pwd_h=no
		ac_cv_header_utime_h=no
		ac_cv_header_sys_ioctl_h=no
		ac_cv_header_sys_param_h=no
		ac_cv_header_sys_resource_h=no
		ac_cv_header_sys_select_h=no
		ac_cv_header_sys_time_h=no
		ac_cv_header_sys_times_h=no
		ac_cv_header_sys_socket_h=no
		ac_cv_func_lstat=yes
		ac_cv_func_times=yes
		ac_cv_func_waitpid=yes
		ac_cv_func_fsync=yes
		ac_cv_func_seekdir=yes
		ac_cv_func_telldir=yes
		ac_cv_func_isinf=yes
		ac_cv_func_isnan=yes
		ac_cv_func_finite=yes
		ac_cv_func_lchown=yes
		ac_cv_func_link=yes
		ac_cv_func_readlink=yes
		ac_cv_func_symlink=yes
		ac_cv_lib_crypt_crypt=no
		ac_cv_func_getpgrp_void=no
		ac_cv_func_memcmp_working=yes
		ac_cv_lib_dl_dlopen=no
		rb_cv_binary_elf=no
		rb_cv_negative_time_t=no
		ac_cv_func_fcntl=yes
		ac_cv_func_flock=yes
		ac_cv_func_gmtime_r=yes
		rb_cv_large_fd_select=yes
		ac_cv_type_struct_timeval=yes
                ac_cv_func_clock_gettime=yes
                ac_cv_func_clock_getres=yes
		ac_cv_func_malloc_usable_size=no
		AS_IF([test "$target_cpu" = x64], [
		    ac_cv_func___builtin_setjmp=no
		    ac_cv_func_round=no
		])
		AC_CHECK_TYPE([NET_LUID], [], [],
			      [@%:@include <winsock2.h>
			      @%:@include <iphlpapi.h>])
		if test x"$ac_cv_type_NET_LUID" = xyes; then
		    AC_DEFINE(HAVE_TYPE_NET_LUID, 1)
		fi
		AC_CHECK_FUNCS(_gmtime64_s)
		AC_CHECK_FUNCS(_wfreopen_s)
		AC_LIBOBJ([langinfo])
		],
[bsdi*], [	LIBS="-lm $LIBS"
		AC_DEFINE(BROKEN_SETREUID, 1)
		AC_DEFINE(BROKEN_SETREGID, 1)
                ac_cv_sizeof_rlim_t=8],
[freebsd*], [	LIBS="-lm $LIBS"
		ac_cv_func_getpeername=no
		ac_cv_func_getsockname=no
		ac_cv_func_shutdown=no
		ac_cv_func_close=no
		],
[netbsd*], [	LIBS="-lm $LIBS"
		],
[dragonfly*], [	LIBS="-lm $LIBS"
		# isinf() and isnan() are macros on DragonFly.
		ac_cv_func_isinf=yes
		ac_cv_func_isnan=yes
		],
[aix*],[	LIBS="-lm $LIBS"
		ac_cv_func_round=no
		],
[nacl], [
  LIBS="-lm $LIBS"
  if test "${nacl_cv_build_variant}" = "newlib"; then
    RUBY_APPEND_OPTION(CPPFLAGS, -DNACL_NEWLIB)
  else
    RUBY_APPEND_OPTION(XCFLAGS, -fPIC)
  fi
  ],
[	LIBS="-lm $LIBS"])

AC_CHECK_LIB(crypt, crypt)      # glibc (GNU/Linux, GNU/Hurd, GNU/kFreeBSD)
AC_CHECK_LIB(dl, dlopen)	# Dynamic linking for SunOS/Solaris and SYSV
AC_CHECK_LIB(dld, shl_load)	# Dynamic linking for HP-UX
AC_CHECK_LIB(socket, shutdown)  # SunOS/Solaris

dnl Checks for header files.
AC_HEADER_DIRENT
dnl AC_HEADER_STDC has been checked in AC_USE_SYSTEM_EXTENSIONS
AC_HEADER_STDBOOL
AC_HEADER_SYS_WAIT

AC_CHECK_HEADERS(a.out.h)
AC_CHECK_HEADERS(atomic.h)
AC_CHECK_HEADERS(direct.h)
AC_CHECK_HEADERS(grp.h)
AC_CHECK_HEADERS(fcntl.h)
AC_CHECK_HEADERS(float.h)
AC_CHECK_HEADERS(ieeefp.h)
AC_CHECK_HEADERS(intrinsics.h)
AC_CHECK_HEADERS(langinfo.h)
AC_CHECK_HEADERS(limits.h)
AC_CHECK_HEADERS(locale.h)
AC_CHECK_HEADERS(malloc.h)
AC_CHECK_HEADERS(malloc/malloc.h)
AC_CHECK_HEADERS(malloc_np.h)
AC_CHECK_HEADERS(net/socket.h)
AC_CHECK_HEADERS(process.h)
AC_CHECK_HEADERS(pwd.h)
AC_CHECK_HEADERS(setjmpex.h)
AC_CHECK_HEADERS(sys/attr.h)
AC_CHECK_HEADERS(sys/fcntl.h)
AC_CHECK_HEADERS(sys/file.h)
AC_CHECK_HEADERS(sys/id.h)
AC_CHECK_HEADERS(sys/ioctl.h)
AC_CHECK_HEADERS(sys/mkdev.h)
AC_CHECK_HEADERS(sys/param.h)
AC_CHECK_HEADERS(sys/prctl.h)
AC_CHECK_HEADERS(sys/resource.h)
AC_CHECK_HEADERS(sys/select.h)
AC_CHECK_HEADERS(sys/sendfile.h)
AC_CHECK_HEADERS(sys/socket.h)
AC_CHECK_HEADERS(sys/syscall.h)
AC_CHECK_HEADERS(sys/sysmacros.h)
AC_CHECK_HEADERS(sys/time.h)
AC_CHECK_HEADERS(sys/times.h)
AC_CHECK_HEADERS(sys/uio.h)
AC_CHECK_HEADERS(sys/utime.h)
AC_CHECK_HEADERS(syscall.h)
AC_CHECK_HEADERS(time.h)
AC_CHECK_HEADERS(ucontext.h)
AC_CHECK_HEADERS(utime.h)

AC_ARG_WITH([gmp],
  [AS_HELP_STRING([--without-gmp],
    [disable GNU GMP to accelerate Bignum operations])],
  [],
  [with_gmp=yes])
AS_IF([test "x$with_gmp" != xno],
  [AC_CHECK_HEADERS(gmp.h)
   AS_IF([test "x$ac_cv_header_gmp_h" != xno],
     AC_SEARCH_LIBS([__gmpz_init], [gmp],
       [AC_DEFINE(HAVE_LIBGMP, 1)]))])

AC_ARG_WITH([jemalloc],
  [AS_HELP_STRING([--with-jemalloc],[use jemalloc allocator])],
  [with_jemalloc=$withval], [with_jemalloc=no])
AS_IF([test "x$with_jemalloc" = xyes],[
  AC_SEARCH_LIBS([malloc_conf], [jemalloc],
    [AC_DEFINE(HAVE_LIBJEMALLOC, 1)], [with_jemalloc=no])
  AC_CHECK_HEADER(jemalloc/jemalloc.h, [
    AC_DEFINE(RUBY_ALTERNATIVE_MALLOC_HEADER, [<jemalloc/jemalloc.h>])
  ])
  AS_IF([test "x$with_jemalloc" = xno], [
    AC_CACHE_CHECK([for jemalloc with JEMALLOC_MANGLE], rb_cv_jemalloc_demangle,
      [AC_LINK_IFELSE([AC_LANG_PROGRAM([@%:@define JEMALLOC_MANGLE 1
      @%:@ifdef RUBY_ALTERNATIVE_MALLOC_HEADER
      @%:@include RUBY_ALTERNATIVE_MALLOC_HEADER
      @%:@else
      @%:@include <jemalloc.h>
      @%:@endif], [return !&malloc_conf])],
      [rb_cv_jemalloc_demangle=yes],
      [rb_cv_jemalloc_demangle=no])
    ])
  ])
  AS_IF([test "x$rb_cv_jemalloc_demangle" = xyes], [
    AC_DEFINE(JEMALLOC_MANGLE)
    with_jemalloc=yes
  ])
  AS_IF([test "x$with_jemalloc" = xyes],
    [
      ac_cv_func_malloc_usable_size=yes
    ],
    [AC_MSG_ERROR([jemalloc requested but not found])
  ])
])

dnl check for large file stuff
mv confdefs.h confdefs1.h
: > confdefs.h
AC_SYS_LARGEFILE
# On 32-bit Solaris, it is safe to define _LARGEFILE_SOURCE
# which is not added by AC_SYS_LARGEFILE.
if test x"$enable_largefile" != xno; then
  AS_CASE(["$target_os"], [solaris*], [
    AC_MSG_CHECKING([wheather _LARGEFILE_SOURCE should be defined])
    AS_CASE(["${ac_cv_sys_file_offset_bits}:${ac_cv_sys_large_files}"],
      ["64:"|"64:no"|"64:unknown"], [
	# insert _LARGEFILE_SOURCE before _FILE_OFFSET_BITS line
	# that is the same order as "getconf LFS_CFLAGS" output
	mv confdefs.h largefile0.h
	: > confdefs.h
	AC_DEFINE(_LARGEFILE_SOURCE)
	cat largefile0.h >> confdefs.h
	rm largefile0.h
	AC_MSG_RESULT([yes])
      ], [AC_MSG_RESULT([no])])
  ])
fi
mv confdefs.h largefile.h
mv confdefs1.h confdefs.h
cat largefile.h >> confdefs.h

AS_CASE(["$target_os"],
    [mingw*], [ac_cv_type_off_t=yes;ac_cv_sizeof_off_t=8],
    [aix*], [
    AS_CASE(["$target_cpu:$ac_cv_sys_large_files"],
	[ppc64:*|powerpc64:*], [],
	[*:no|*:unknown], [],
	[
	    # AIX currently does not support a 32-bit call to posix_fadvise()
	    # if _LARGE_FILES is defined.
	    ac_cv_func_posix_fadvise=no
	])
    ])

AC_C_BIGENDIAN
AC_C_CONST
AC_C_CHAR_UNSIGNED
AC_C_INLINE
AC_C_VOLATILE
AC_C_TYPEOF

AS_CASE(":$ac_cv_c_const:$ac_cv_c_volatile:",
    [*:no:*], [AC_MSG_ERROR(ANSI C-conforming const and volatile are mandatory)])

AC_CHECK_TYPES([long long, off_t])

AC_CACHE_CHECK([char bit], [rb_cv_char_bit],
    [test "$universal_binary" = yes && cross_compiling=yes
    AC_COMPUTE_INT([rb_cv_char_bit], [CHAR_BIT],
	[AC_INCLUDES_DEFAULT([@%:@include <limits.h>])], [rb_cv_char_bit=8])
    test "$universal_binary" = yes && cross_compiling=$real_cross_compiling])

dnl RUBY_CHECK_SIZEOF [typename], [maybe same size types], [macros], [include]
AC_DEFUN([RUBY_CHECK_SIZEOF],
[dnl
AS_VAR_PUSHDEF([rbcv_var], [rbcv_sizeof_var])dnl
AS_VAR_PUSHDEF([cond], [rbcv_sizeof_cond])dnl
AS_VAR_PUSHDEF([t], [rbcv_sizeof_type])dnl
AS_VAR_PUSHDEF([s], [rbcv_sizeof_size])dnl
]
[m4_bmatch([$1], [\.], [], [if test "$universal_binary" = yes; then])
AC_CACHE_CHECK([size of $1], [AS_TR_SH([ac_cv_sizeof_$1])], [
    unset AS_TR_SH(ac_cv_sizeof_$1)
    rbcv_var="
typedef m4_bpatsubst([$1], [\..*]) ac__type_sizeof_;
static ac__type_sizeof_ *rbcv_ptr;
@%:@define AS_TR_CPP(SIZEOF_$1) sizeof((*rbcv_ptr)[]m4_bmatch([$1], [\.], .m4_bpatsubst([$1], [^[^.]*\.])))
"
    m4_ifval([$2], [test -z "${AS_TR_SH(ac_cv_sizeof_$1)+set}" && {
    for t in $2; do
	AC_COMPILE_IFELSE(
	    [AC_LANG_BOOL_COMPILE_TRY(AC_INCLUDES_DEFAULT([$4]
		[$rbcv_var]),
		[AS_TR_CPP(SIZEOF_$1) == sizeof($t)])], [
		AS_TR_SH(ac_cv_sizeof_$1)=AS_TR_CPP([SIZEOF_]$t)
		break])
    done
    }], [
	AC_COMPUTE_INT([AS_TR_SH(ac_cv_sizeof_$1)], [AS_TR_CPP(SIZEOF_$1)],
	    [AC_INCLUDES_DEFAULT([$4])
$rbcv_var],
	    [AS_TR_SH(ac_cv_sizeof_$1)=])
    ])
    unset cond
    m4_ifval([$3], [test -z "${AS_TR_SH(ac_cv_sizeof_$1)+set}" && {
    for s in 32 64 128; do
	for t in $3; do
	    cond="${cond}
@%:@${cond+el}if defined(__${t}${s}__) || defined(__${t}${s}) || defined(_${t}${s}) || defined(${t}${s})"
	    hdr="AC_INCLUDES_DEFAULT([$4
@%:@if defined(__${t}${s}__) || defined(__${t}${s}) || defined(_${t}${s}) || defined(${t}${s})
@%:@ define AS_TR_CPP(HAVE_$1) 1
@%:@else
@%:@ define AS_TR_CPP(HAVE_$1) 0
@%:@endif])"
	    AC_COMPILE_IFELSE([AC_LANG_BOOL_COMPILE_TRY([$hdr], [!AS_TR_CPP(HAVE_$1)])], [continue])
	    AC_COMPILE_IFELSE([AC_LANG_BOOL_COMPILE_TRY([$hdr]
				[$rbcv_var],
				[AS_TR_CPP(HAVE_$1) == (AS_TR_CPP(SIZEOF_$1) == ($s / $rb_cv_char_bit))])],
		[AS_TR_SH(ac_cv_sizeof_$1)="${AS_TR_SH(ac_cv_sizeof_$1)+${AS_TR_SH(ac_cv_sizeof_$1)-} }${t}${s}"; continue])
	    AC_COMPILE_IFELSE([AC_LANG_BOOL_COMPILE_TRY([$hdr]
[
@%:@if AS_TR_CPP(HAVE_$1)
$rbcv_var
@%:@else
@%:@define AS_TR_CPP(SIZEOF_$1) 0
@%:@endif
],
		    [AS_TR_CPP(HAVE_$1) == (AS_TR_CPP(SIZEOF_$1) == (m4_bmatch([$2], [^[0-9][0-9]*$], [$2], [($s / $rb_cv_char_bit)])))])],
		[AS_TR_SH(ac_cv_sizeof_$1)="${AS_TR_SH(ac_cv_sizeof_$1)+${AS_TR_SH(ac_cv_sizeof_$1)-} }${t}${s}m4_bmatch([$2], [^[0-9][0-9]*$], [:$2])"])
	done
    done
    }])
    test "${AS_TR_SH(ac_cv_sizeof_$1)@%:@@<:@1-9@:>@}" = "${AS_TR_SH(ac_cv_sizeof_$1)}" &&
    m4_ifval([$2][$3],
	[test "${AS_TR_SH(ac_cv_sizeof_$1)@%:@SIZEOF_}" = "${AS_TR_SH(ac_cv_sizeof_$1)}" && ]){
    test "$universal_binary" = yes && cross_compiling=yes
    AC_COMPUTE_INT([t], AS_TR_CPP(SIZEOF_$1), [AC_INCLUDES_DEFAULT([$4])]
[${cond+$cond
@%:@else}
$rbcv_var
${cond+@%:@endif}
@%:@ifndef AS_TR_CPP(SIZEOF_$1)
@%:@define AS_TR_CPP(SIZEOF_$1) 0
@%:@endif], [t=0])
    test "$universal_binary" = yes && cross_compiling=$real_cross_compiling
    if test ${t-0} != 0; then
	AS_TR_SH(ac_cv_sizeof_$1)="${AS_TR_SH(ac_cv_sizeof_$1)+${AS_TR_SH(ac_cv_sizeof_$1)-} }${t}"
    fi
    }
    : ${AS_TR_SH(ac_cv_sizeof_$1)=0}
])
{
    unset cond
    for t in ${AS_TR_SH(ac_cv_sizeof_$1)-}; do
	AS_CASE(["$t"],
	[[[0-9]*|SIZEOF_*]], [
	    ${cond+echo "@%:@else"}
	    echo "[@%:@define ]AS_TR_CPP(SIZEOF_$1) $t"
	    break
	    ],
	[
	    s=`expr $t : ['.*[^0-9]\([0-9][0-9]*\)$']`
	    AS_CASE([$t], [*:*], [t="${t%:*}"], [s=`expr $s / $rb_cv_char_bit`])
	    echo "@%:@${cond+el}if defined(__${t}__) || defined(__${t}) || defined(_${t}) || defined($t)"
	    echo "@%:@define AS_TR_CPP(SIZEOF_$1) $s"
	    cond=1
	    ])
    done
    ${cond+echo "@%:@endif"}
} >> confdefs.h
m4_bmatch([$1], [\.], [], [else
AC_CHECK_SIZEOF([$1], 0, [$4])
fi])
AS_VAR_POPDEF([rbcv_var])dnl
AS_VAR_POPDEF([cond])dnl
AS_VAR_POPDEF([t])dnl
AS_VAR_POPDEF([s])dnl
])

RUBY_CHECK_SIZEOF(int, [], [ILP])
RUBY_CHECK_SIZEOF(short)
RUBY_CHECK_SIZEOF(long, [int], [ILP LP])
RUBY_CHECK_SIZEOF(long long)
RUBY_CHECK_SIZEOF(__int64, [8], [ILP LP])
RUBY_CHECK_SIZEOF(__int128, [16], [ILP LP])
RUBY_CHECK_SIZEOF(off_t)
RUBY_CHECK_SIZEOF(void*, [int long "long long"], [ILP LP LLP])
RUBY_CHECK_SIZEOF(float)
RUBY_CHECK_SIZEOF(double)
RUBY_CHECK_SIZEOF(time_t, [long "long long"], [], [@%:@include <time.h>])
RUBY_CHECK_SIZEOF(clock_t, [], [], [@%:@include <time.h>])

AC_CACHE_CHECK(packed struct attribute, rb_cv_packed_struct,
    [rb_cv_packed_struct=no
    for mac in \
	"__pragma(pack(push, 1)) x __pragma(pack(pop))" \
	"x __attribute__((packed))" \
	; do
	AC_TRY_COMPILE([@%:@define PACKED_STRUCT(x) $mac
			PACKED_STRUCT(struct { int a; });], [],
		[rb_cv_packed_struct=$mac; break])
    done])
packed_struct_unaligned=x
if test "$rb_cv_packed_struct" != no; then
    AC_DEFINE_UNQUOTED([PACKED_STRUCT(x)], [$rb_cv_packed_struct])
else
    AC_DEFINE_UNQUOTED([PACKED_STRUCT(x)], x)
fi
AC_DEFINE_UNQUOTED(PACKED_STRUCT_UNALIGNED(x), $packed_struct_unaligned)

AC_DEFUN([RUBY_CHECK_PRINTF_PREFIX], [
AC_CACHE_CHECK([for printf prefix for $1], [rb_cv_pri_prefix_]AS_TR_SH($1),[
    [rb_cv_pri_prefix_]AS_TR_SH($1)=[NONE]
    RUBY_WERROR_FLAG(RUBY_APPEND_OPTIONS(CFLAGS, $rb_cv_wsuppress_flags)
    for pri in $2; do
        AC_TRY_COMPILE(
            [@%:@include <stdio.h>
	    @%:@include <stddef.h>
            @%:@ifdef __GNUC__
            @%:@define PRINTF_ARGS(decl, string_index, first_to_check) \
              decl __attribute__((format(printf, string_index, first_to_check)))
            @%:@else
            @%:@define PRINTF_ARGS(decl, string_index, first_to_check) decl
            @%:@endif
	    PRINTF_ARGS(void test_sprintf(const char*, ...), 1, 2);],
            [printf("%]${pri}[d", (]$1[)42);
            test_sprintf("%]${pri}[d", (]$1[)42);],
            [rb_cv_pri_prefix_]AS_TR_SH($1)[=[$pri]; break])
    done)])
if test "[$rb_cv_pri_prefix_]AS_TR_SH($1)" != NONE; then
    AC_DEFINE_UNQUOTED([PRI_]m4_ifval($3,$3,AS_TR_CPP(m4_bpatsubst([$1],[_t$])))[_PREFIX],
        "[$rb_cv_pri_prefix_]AS_TR_SH($1)")
fi
])

if test "x$ac_cv_type_long_long" = xyes; then
    RUBY_CHECK_PRINTF_PREFIX(long long, ll I64, LL)
elif test "x$ac_cv_type___int64" = xyes; then
    RUBY_CHECK_PRINTF_PREFIX(__int64, ll I64, LL)
fi

dnl RUBY_CHECK_SIGNEDNESS [typename] [if-signed] [if-unsigned] [included]
AC_DEFUN([RUBY_CHECK_SIGNEDNESS], [dnl
    AC_COMPILE_IFELSE([AC_LANG_BOOL_COMPILE_TRY([AC_INCLUDES_DEFAULT([$4])], [($1)-1 > 0])],
		      [$3], [$2])])

dnl RUBY_REPLACE_TYPE [typename] [default type] [macro type] [included]
AC_DEFUN([RUBY_REPLACE_TYPE], [dnl
    AC_CHECK_TYPE([$1],
		  [n="patsubst([$1],["],[\\"])"],
		  [n="patsubst([$2],["],[\\"])"],
		  [$4])
    AC_CACHE_CHECK([for convertible type of [$1]], rb_cv_[$1]_convertible, [
	u= t=
	AS_CASE(["$n "],
	  [*" signed "*], [ ],
	  [*" unsigned "*], [
	    u=U],
	  [RUBY_CHECK_SIGNEDNESS($n, [], [u=U], [$4])])
	if test x"$t" = x; then
	    for t in "long long" long int short; do
		test -n "$u" && t="unsigned $t"
		AC_COMPILE_IFELSE(
		    [AC_LANG_BOOL_COMPILE_TRY([AC_INCLUDES_DEFAULT([$4])]
			[typedef $n rbcv_conftest_target_type;
			typedef $t rbcv_conftest_replace_type;
			extern rbcv_conftest_target_type rbcv_conftest_var;
			extern rbcv_conftest_replace_type rbcv_conftest_var;
			extern rbcv_conftest_target_type rbcv_conftest_func(void);
			extern rbcv_conftest_replace_type rbcv_conftest_func(void);
			], [sizeof(rbcv_conftest_target_type) == sizeof(rbcv_conftest_replace_type)])],
		    [n="$t"; break])
	    done
	fi
	AS_CASE([" $n "],
	  [*" long long "*], [
	    t=LL],
	  [*" long "*], [
	    t=LONG],
	  [
	    t=INT])
	rb_cv_[$1]_convertible=${u}${t}])
    if test "${AS_TR_SH(ac_cv_type_[$1])}" = "yes"; then
	n="$1"
    else
	AS_CASE(["${rb_cv_[$1]_convertible}"],
		[*LL], [n="long long"],
		[*LONG], [n="long"],
		[n="int"])
	AS_CASE(["${rb_cv_[$1]_convertible}"],
		[U*], [n="unsigned $n"])
    fi
    AS_CASE("${rb_cv_[$1]_convertible}", [U*], [u=+1], [u=-1])
    AC_DEFINE_UNQUOTED(rb_[$1], $n)
    AC_DEFINE_UNQUOTED([SIGNEDNESS_OF_]AS_TR_CPP($1), $u)
    AC_DEFINE_UNQUOTED([$3]2NUM[(v)], [${rb_cv_[$1]_convertible}2NUM(v)])
    AC_DEFINE_UNQUOTED(NUM2[$3][(v)], [NUM2${rb_cv_[$1]_convertible}(v)])
    AC_DEFINE_UNQUOTED(PRI_[$3]_PREFIX,
	[PRI_`echo ${rb_cv_[$1]_convertible} | sed ['s/^U//']`_PREFIX])
])
RUBY_REPLACE_TYPE(pid_t, int, PIDT)
RUBY_REPLACE_TYPE(uid_t, int, UIDT)
RUBY_REPLACE_TYPE(gid_t, int, GIDT)
RUBY_REPLACE_TYPE(time_t, [], TIMET, [@%:@include <time.h>])
RUBY_REPLACE_TYPE(dev_t, [int long "long long"], DEVT)
RUBY_REPLACE_TYPE(mode_t, ["unsigned int" long], MODET, [@%:@include <sys/stat.h>])
RUBY_REPLACE_TYPE(rlim_t, [int long "long long"], RLIM, [
@%:@ifdef HAVE_SYS_TYPES_H
@%:@include <sys/types.h>
@%:@endif
@%:@ifdef HAVE_SYS_TYPES_H
@%:@include <sys/time.h>
@%:@endif
@%:@include <sys/resource.h>
])
RUBY_REPLACE_TYPE(off_t, [], OFFT)
RUBY_REPLACE_TYPE(clockid_t, [], CLOCKID)

AC_CACHE_CHECK(for prototypes, rb_cv_have_prototypes,
  [AC_TRY_COMPILE([int foo(int x) { return 0; }], [return foo(10);],
	rb_cv_have_prototypes=yes,
	rb_cv_have_prototypes=no)])
if test "$rb_cv_have_prototypes" = yes; then
  AC_DEFINE(HAVE_PROTOTYPES)
fi

AC_CACHE_CHECK(token paste string, rb_cv_tokenpaste,
  [AC_TRY_COMPILE([@%:@define paste(a,b) a@%:@@%:@b],
		  [int xy = 1; return paste(x,y);],
		  rb_cv_tokenpaste=ansi,
		  rb_cv_tokenpaste=knr)])
if test "$rb_cv_tokenpaste" = ansi; then
  AC_DEFINE(TOKEN_PASTE(x,y),[x@%:@@%:@y])
else
  AC_DEFINE(TOKEN_PASTE(x,y),[x/**/y])
fi

AC_CACHE_CHECK(stringization, rb_cv_stringization, [
  rb_cv_stringization=no
  for string in "#expr" '"expr"'; do
    AC_COMPILE_IFELSE([
      AC_LANG_BOOL_COMPILE_TRY([
#define STRINGIZE0(expr) $string
#define STRINGIZE(expr) STRINGIZE0(expr)
#undef real_test_for_stringization
#define test_for_stringization -.real_test_for_stringization.-
const char stringized[[]] = STRINGIZE(test_for_stringization);
], [sizeof(stringized) == 32])],
      [rb_cv_stringization="$string"; break],
      [rb_cv_stringization=no])
  done]
)
AC_DEFINE(STRINGIZE(expr),STRINGIZE0(expr))
if test x"$rb_cv_stringization" != xno -a "$rb_cv_stringization" != "#expr"; then
  AC_DEFINE_UNQUOTED(STRINGIZE0(expr),$rb_cv_stringization)
  AC_DEFINE(OLD_FASHIONED_STRINGIZATION,1)
fi

AC_CACHE_CHECK([string literal concatenation],
  rb_cv_string_literal_concatenation, [
  AC_COMPILE_IFELSE([
    AC_LANG_BOOL_COMPILE_TRY([
const char concatenated_literal[[]] = "literals" "to"
  "be" "concatenated.";
], [sizeof(concatenated_literal) == 26])],
    [rb_cv_string_literal_concatenation=yes],
    [rb_cv_string_literal_concatenation=no])]
)
if test "$rb_cv_string_literal_concatenation" = no; then
  AC_DEFINE(NO_STRING_LITERAL_CONCATENATION,1)
fi

AC_CACHE_CHECK(for variable length prototypes and stdarg.h, rb_cv_stdarg,
  [AC_TRY_COMPILE([
#include <stdarg.h>
int foo(int x, ...) {
	va_list va;
	va_start(va, x);
	va_arg(va, int);
	va_arg(va, char *);
	va_arg(va, double);
	return 0;
}
], [return foo(10, "", 3.14);],
	rb_cv_stdarg=yes,
	rb_cv_stdarg=no)])
if test "$rb_cv_stdarg" = yes; then
  AC_DEFINE(HAVE_STDARG_PROTOTYPES)
fi

AC_CACHE_CHECK(for variable length macro, rb_cv_va_args_macro,
  [AC_TRY_COMPILE([
int foo(int x, ...);
@%:@define FOO(a, ...) foo(a, @%:@@%:@__VA_ARGS__)
], [FOO(1);FOO(1,2);FOO(1,2,3);],
  rb_cv_va_args_macro=yes,
  rb_cv_va_args_macro=no)])
if test "$rb_cv_va_args_macro" = yes; then
  AC_DEFINE(HAVE_VA_ARGS_MACRO)
fi

AC_DEFUN([RUBY_DEFINE_IF], [dnl
    m4_ifval([$1], [AS_LITERAL_IF([$1], [], [test "X$1" = X || ])cat <<EOH >> confdefs.h
@%:@if $1
EOH
])dnl
AC_DEFINE_UNQUOTED($2, $3)dnl
    m4_ifval([$1], [AS_LITERAL_IF([$1], [], [test "X$1" = X || ])cat <<EOH >> confdefs.h
@%:@endif /* $1 */
EOH
])dnl
])dnl

dnl RUBY_DECL_ATTRIBUTE(attrib, macroname, cachevar, condition, type, code)
AC_DEFUN([RUBY_DECL_ATTRIBUTE], [dnl
m4_ifval([$2], dnl
  [AS_VAR_PUSHDEF([attrib], m4_bpatsubst([$2], [(.*)], []))], dnl
  [AS_VAR_PUSHDEF([attrib], m4_toupper(m4_format(%.4s, [$5]))[_]AS_TR_CPP($1))] dnl
)dnl
m4_ifval([$3], dnl
  [AS_VAR_PUSHDEF([rbcv],[$3])], dnl
  [AS_VAR_PUSHDEF([rbcv],[rb_cv_]m4_format(%.4s, [$5])[_][$1])]dnl
)dnl
m4_pushdef([attrib_code],[m4_bpatsubst([$1],["],[\\"])])dnl
m4_pushdef([attrib_params],[m4_bpatsubst([$2(x)],[^[^()]*(\([^()]*\)).*],[\1])])dnl
m4_ifval([$4], [rbcv_cond=["$4"]; test "$rbcv_cond" || unset rbcv_cond])
AC_CACHE_CHECK(for m4_ifval([$2],[m4_bpatsubst([$2], [(.*)], [])],[$1]) [$5] attribute, rbcv, dnl
[rbcv=x
RUBY_WERROR_FLAG([
for mac in \
    "__attribute__ ((attrib_code)) x" \
    "x __attribute__ ((attrib_code))" \
    "__declspec(attrib_code) x" \
    x; do
  m4_ifval([$4],mac="$mac"${rbcv_cond+" /* only if $rbcv_cond */"})
  AC_TRY_COMPILE(
    m4_ifval([$4],${rbcv_cond+[@%:@if ]$rbcv_cond})
[@%:@define ]attrib[](attrib_params)[ $mac]
m4_ifval([$4],${rbcv_cond+[@%:@else]}
${rbcv_cond+[@%:@define ]attrib[](attrib_params)[ x]}
${rbcv_cond+[@%:@endif]})
$6
@%:@define mesg ("")
    attrib[](attrib_params)[;], [],
    [rbcv="$mac"; break])
done
])])
if test "$rbcv" != x; then
    RUBY_DEFINE_IF(m4_ifval([$4],[${rbcv_cond}]), attrib[](attrib_params)[], $rbcv)
fi
m4_ifval([$4], [unset rbcv_cond]) dnl
m4_popdef([attrib_params])dnl
m4_popdef([attrib_code])dnl
AS_VAR_POPDEF([attrib])dnl
AS_VAR_POPDEF([rbcv])dnl
])

dnl RUBY_FUNC_ATTRIBUTE(attrib, macroname, cachevar, condition)
AC_DEFUN([RUBY_FUNC_ATTRIBUTE], [dnl
    RUBY_DECL_ATTRIBUTE([$1], [$2], [$3], [$4],
	[function], [@%:@define x int conftest_attribute_check(void)]
    )
])

dnl RUBY_TYPE_ATTRIBUTE(attrib, macroname, cachevar, condition)
AC_DEFUN([RUBY_TYPE_ATTRIBUTE], [dnl
    RUBY_DECL_ATTRIBUTE([$1], [$2], [$3], [$4],
	[type], [
@%:@define x struct conftest_attribute_check {int i;}
])
])

RUBY_FUNC_ATTRIBUTE(__const__, CONSTFUNC)
RUBY_FUNC_ATTRIBUTE(__pure__, PUREFUNC)
RUBY_FUNC_ATTRIBUTE(__noreturn__, NORETURN)
RUBY_FUNC_ATTRIBUTE(__deprecated__, DEPRECATED)
RUBY_FUNC_ATTRIBUTE(__deprecated__("by "@%:@n), DEPRECATED_BY(n,x), rb_cv_func_deprecated_by)
RUBY_TYPE_ATTRIBUTE(__deprecated__ mesg, DEPRECATED_TYPE(mesg,x), rb_cv_type_deprecated)
RUBY_FUNC_ATTRIBUTE(__noinline__, NOINLINE)
RUBY_FUNC_ATTRIBUTE(__always_inline__, ALWAYS_INLINE)
RUBY_FUNC_ATTRIBUTE(__warn_unused_result__, WARN_UNUSED_RESULT)
RUBY_FUNC_ATTRIBUTE(__unused__, MAYBE_UNUSED)
RUBY_FUNC_ATTRIBUTE(__error__ mesg, ERRORFUNC(mesg,x), rb_cv_func___error__)
RUBY_FUNC_ATTRIBUTE(__warning__ mesg, WARNINGFUNC(mesg,x), rb_cv_func___warning__)
RUBY_FUNC_ATTRIBUTE(__weak__, WEAK, rb_cv_func_weak)
if test "$rb_cv_func_weak" != x; then
   AC_DEFINE(HAVE_FUNC_WEAK)
fi

if_i386=${universal_binary+[defined __i386__]}
RUBY_FUNC_ATTRIBUTE(__stdcall__,  FUNC_STDCALL,  rb_cv_func_stdcall,  ${if_i386})
RUBY_FUNC_ATTRIBUTE(__cdecl__,    FUNC_CDECL,    rb_cv_func_cdecl,    ${if_i386})
RUBY_FUNC_ATTRIBUTE(__fastcall__, FUNC_FASTCALL, rb_cv_func_fastcall, ${if_i386})
RUBY_FUNC_ATTRIBUTE(__optimize__("O0"), FUNC_UNOPTIMIZED, rb_cv_func_unoptimized)
RUBY_FUNC_ATTRIBUTE(__optimize__("-Os","-fomit-frame-pointer"), FUNC_MINIMIZED, rb_cv_func_minimized)

if test "$GCC" = yes; then
    AC_CACHE_CHECK([for function alias], [rb_cv_gcc_function_alias],
	[rb_cv_gcc_function_alias=no
	for a in alias weak,alias; do
	    AC_TRY_LINK([void foo(void) {}
		void bar(void) __attribute__(($a("foo")));], [bar()],
		[rb_cv_gcc_function_alias=$a; break])
	done])
    if test "$rb_cv_gcc_function_alias" != no; then
	AC_DEFINE(HAVE_ATTRIBUTE_FUNCTION_ALIAS)
	AC_DEFINE_UNQUOTED([RUBY_ALIAS_FUNCTION_TYPE(type, prot, name, args)],
			   [type prot __attribute__(($rb_cv_gcc_function_alias(@%:@name)));])
	AC_DEFINE_UNQUOTED([RUBY_ALIAS_FUNCTION_VOID(prot, name, args)],
			   [RUBY_ALIAS_FUNCTION_TYPE(void, prot, name, args)])
    fi

    AC_CACHE_CHECK([for __atomic builtins], [rb_cv_gcc_atomic_builtins], [
	AC_TRY_LINK([unsigned char atomic_var;],
		    [
			__atomic_exchange_n(&atomic_var, 0, __ATOMIC_SEQ_CST);
			__atomic_exchange_n(&atomic_var, 1, __ATOMIC_SEQ_CST);
			__atomic_fetch_add(&atomic_var, 1, __ATOMIC_SEQ_CST);
			__atomic_fetch_sub(&atomic_var, 1, __ATOMIC_SEQ_CST);
			__atomic_or_fetch(&atomic_var, 1, __ATOMIC_SEQ_CST);
		    ],
		    [rb_cv_gcc_atomic_builtins=yes],
		    [rb_cv_gcc_atomic_builtins=no])])
    if test "$rb_cv_gcc_atomic_builtins" = yes; then
	AC_DEFINE(HAVE_GCC_ATOMIC_BUILTINS)
    fi

    AC_CACHE_CHECK([for __sync builtins], [rb_cv_gcc_sync_builtins], [
	AC_TRY_LINK([unsigned char atomic_var;],
		    [
			__sync_lock_test_and_set(&atomic_var, 0);
			__sync_lock_test_and_set(&atomic_var, 1);
			__sync_fetch_and_add(&atomic_var, 1);
			__sync_fetch_and_sub(&atomic_var, 1);
			__sync_or_and_fetch(&atomic_var, 1);
			__sync_val_compare_and_swap(&atomic_var, 0, 1);
		    ],
		    [rb_cv_gcc_sync_builtins=yes],
		    [rb_cv_gcc_sync_builtins=no])])
    if test "$rb_cv_gcc_sync_builtins" = yes; then
	AC_DEFINE(HAVE_GCC_SYNC_BUILTINS)
    fi

    AC_CACHE_CHECK(for __builtin_unreachable, rb_cv_func___builtin_unreachable,
    [RUBY_WERROR_FLAG(
    [AC_TRY_LINK([volatile int zero;],
	[if (zero) __builtin_unreachable();],
	[rb_cv_func___builtin_unreachable=yes],
	[rb_cv_func___builtin_unreachable=no])
    ])
    ])
    if test "$rb_cv_func___builtin_unreachable" = yes; then
	AC_DEFINE_UNQUOTED(UNREACHABLE, [__builtin_unreachable()])
    fi
fi

AC_CACHE_CHECK(for exported function attribute, rb_cv_func_exported, [
rb_cv_func_exported=no
RUBY_WERROR_FLAG([
for mac in '__attribute__ ((__visibility__("default")))' '__declspec(dllexport)'; do
  AC_TRY_COMPILE([@%:@define RUBY_FUNC_EXPORTED $mac extern
    RUBY_FUNC_EXPORTED void conftest_attribute_check(void);], [],
    [rb_cv_func_exported="$mac"; break])
done
])])
if test "$rb_cv_func_exported" != no; then
    AC_DEFINE_UNQUOTED(RUBY_FUNC_EXPORTED, [$rb_cv_func_exported extern])
fi

RUBY_APPEND_OPTION(XCFLAGS, -DRUBY_EXPORT)

AC_CACHE_CHECK(for function name string predefined identifier,
    rb_cv_function_name_string,
    [rb_cv_function_name_string=no
    RUBY_WERROR_FLAG([
	for func in __func__ __FUNCTION__; do
	    AC_TRY_LINK([@%:@include <stdio.h>],
			[puts($func);],
			[rb_cv_function_name_string=$func
			break])
	done
    ])]
)
if test "$rb_cv_function_name_string" != no; then
    AC_DEFINE_UNQUOTED(RUBY_FUNCTION_NAME_STRING, [$rb_cv_function_name_string])
fi

AC_CACHE_CHECK(if enum over int is allowed, rb_cv_enum_over_int, [
    rb_cv_enum_over_int=no
    if test "x$ac_cv_type_long_long" = xyes; then
	type="unsigned long long" max="ULLONG_MAX"
    else
	type="unsigned long" max="ULONG_MAX"
    fi
    RUBY_WERROR_FLAG([
        AC_COMPILE_IFELSE([
            AC_LANG_BOOL_COMPILE_TRY([
                    @%:@include <limits.h>
                    enum {conftest_max = $max};
                ], [
                    (conftest_max == $max) &&
                    (sizeof(conftest_max) == sizeof($type))
                ]
	    )],
	    [rb_cv_enum_over_int=yes],
	    [rb_cv_enum_over_int=no]
	)
    ])
])
if test $rb_cv_enum_over_int = yes; then
    AC_DEFINE(ENUM_OVER_INT, 1)
fi

dnl Check whether we need to define sys_nerr locally
AC_CHECK_DECLS([sys_nerr], [], [], [$ac_includes_default
@%:@include <errno.h>])

AC_CHECK_DECLS([getenv])

AS_CASE(["$target_cpu"],
[alpha*|sh4|sh4el|sh4eb], [AS_CASE(["$target_os"::"$GCC"],
		[*::yes],  # gcc
			[CFLAGS="-mieee $CFLAGS"],
		[osf*],    # ccc
			[CFLAGS="-ieee $CFLAGS"],
		)],
[sparc*], [AC_LIBOBJ([sparc])])

ac_cv_header_net_socket_h=${ac_cv_header_net_socket_h=no}
if test "$ac_cv_header_net_socket_h" = yes; then
    ac_cv_header_sys_socket_h=${ac_cv_header_sys_socket_h=no}
else
    ac_cv_header_sys_socket_h=${ac_cv_header_sys_socket_h=yes}
fi


AC_TYPE_SIZE_T
RUBY_CHECK_SIGNEDNESS(size_t, [AC_MSG_ERROR(size_t is signed)], [],
		      [@%:@include <sys/types.h>])
RUBY_CHECK_SIZEOF(size_t, [int long void*], [], [@%:@include <sys/types.h>])
RUBY_CHECK_SIZEOF(ptrdiff_t, size_t, [], [@%:@include <stddef.h>])
RUBY_CHECK_PRINTF_PREFIX(size_t, z)
RUBY_CHECK_PRINTF_PREFIX(ptrdiff_t, t)
AC_STRUCT_ST_BLKSIZE
AC_STRUCT_ST_BLOCKS
AC_STRUCT_ST_RDEV
RUBY_CHECK_SIZEOF([struct stat.st_size], [off_t int long "long long"], [], [@%:@include <sys/stat.h>])
if test "$ac_cv_member_struct_stat_st_blocks" = yes; then
    RUBY_CHECK_SIZEOF([struct stat.st_blocks], [off_t int long "long long"], [], [@%:@include <sys/stat.h>])
fi
RUBY_CHECK_SIZEOF([struct stat.st_ino], [long "long long"], [], [@%:@include <sys/stat.h>])
AC_CHECK_MEMBERS([struct stat.st_atim])
AC_CHECK_MEMBERS([struct stat.st_atimespec])
AC_CHECK_MEMBERS([struct stat.st_atimensec])
AC_CHECK_MEMBERS([struct stat.st_mtim])
AC_CHECK_MEMBERS([struct stat.st_mtimespec])
AC_CHECK_MEMBERS([struct stat.st_mtimensec])
AC_CHECK_MEMBERS([struct stat.st_ctim])
AC_CHECK_MEMBERS([struct stat.st_ctimespec])
AC_CHECK_MEMBERS([struct stat.st_ctimensec])
AC_CHECK_MEMBERS([struct stat.st_birthtimespec])

AC_CHECK_TYPES([struct timeval], [], [], [@%:@ifdef HAVE_TIME_H
@%:@include <time.h>
@%:@endif
@%:@ifdef HAVE_SYS_TIME_H
@%:@include <sys/time.h>
@%:@endif])

if test "${ac_cv_type_struct_timeval}" = yes; then
    RUBY_CHECK_SIZEOF([struct timeval.tv_sec], [time_t long "long long"], [],
		      [@%:@ifdef HAVE_TIME_H
@%:@include <time.h>
@%:@endif
@%:@ifdef HAVE_SYS_TIME_H
@%:@include <sys/time.h>
@%:@endif])
    AS_CASE(${ac_cv_sizeof_struct_timeval_tv_sec},
	    [SIZEOF_INT], [t=int],
	    [SIZEOF_LONG], [t=long],
	    [SIZEOF_LONG_LONG], [t=LONG_LONG],
	    [t=])
    if test "${t}" != ""; then
	AC_DEFINE_UNQUOTED(TYPEOF_TIMEVAL_TV_SEC, [$t])
    fi
fi

AC_CHECK_TYPES([struct timespec], [], [], [@%:@ifdef HAVE_TIME_H
@%:@include <time.h>
@%:@endif
@%:@ifdef HAVE_SYS_TIME_H
@%:@include <sys/time.h>
@%:@endif])

AC_CHECK_TYPES([struct timezone], [], [], [@%:@ifdef HAVE_TIME_H
@%:@ include <time.h>
@%:@endif
@%:@ifdef HAVE_SYS_TIME_H
@%:@ include <sys/time.h>
@%:@endif])

AC_CHECK_TYPES([clockid_t], [], [], [@%:@ifdef HAVE_TIME_H
@%:@ include <time.h>
@%:@endif
@%:@ifdef HAVE_SYS_TIME_H
@%:@ include <sys/time.h>
@%:@endif])

AC_CACHE_VAL([rb_cv_large_fd_select],
    [AC_CHECK_TYPE(fd_mask, [rb_cv_large_fd_select=yes], [rb_cv_large_fd_select=no])])
if test "$rb_cv_large_fd_select" = yes; then
    AC_DEFINE(HAVE_RB_FD_INIT, 1)
fi

dnl RUBY_DEFINT TYPENAME, SIZE, [UNSIGNED], [INCLUDES = DEFAULT-INCLUDES]
AC_DEFUN([RUBY_DEFINT], [dnl
AS_VAR_PUSHDEF([cond], [rb_defint_cond])dnl
AS_VAR_PUSHDEF([type], [rb_defint_type])dnl
AC_CACHE_CHECK([for $1], [rb_cv_type_$1],
[AC_COMPILE_IFELSE([AC_LANG_PROGRAM([AC_INCLUDES_DEFAULT([$4])
typedef $1 t; int s = sizeof(t) == 42;])],
   [rb_cv_type_$1=yes],
   [AS_CASE([m4_bmatch([$2], [^[1-9][0-9]*$], $2, [$ac_cv_sizeof_]AS_TR_SH($2))],
    ["1"], [ rb_cv_type_$1="m4_if([$3], [], [signed ], [$3 ])char"],
    ["$ac_cv_sizeof_short"], [ rb_cv_type_$1="m4_if([$3], [], [], [$3 ])short"],
    ["$ac_cv_sizeof_int"], [ rb_cv_type_$1="m4_if([$3], [], [], [$3 ])int"],
    ["$ac_cv_sizeof_long"], [ rb_cv_type_$1="m4_if([$3], [], [], [$3 ])long"],
    ["$ac_cv_sizeof_long_long"], [ rb_cv_type_$1="m4_if([$3], [], [], [$3 ])long long"],
    ["${ac_cv_sizeof___int64@%:@*:}"], [ rb_cv_type_$1="m4_if([$3], [], [], [$3 ])__int64"],
    ["${ac_cv_sizeof___int128@%:@*:}"], [ rb_cv_type_$1="m4_if([$3], [], [], [$3 ])__int128"],
    [ rb_cv_type_$1=no])])])
if test "${rb_cv_type_$1}" != no; then
    type="${rb_cv_type_$1@%:@@%:@unsigned }"
    AS_IF([test "$type" != yes && eval 'test -n "${ac_cv_sizeof_'$type'+set}"'], [
	eval cond='"${ac_cv_sizeof_'$type'}"'
	AS_CASE([$cond], [*:*], [
	    cond=AS_TR_CPP($type)
	    echo "@%:@if defined SIZEOF_"$cond" && SIZEOF_"$cond" > 0" >> confdefs.h
	], [cond=])
    ], [cond=])
    AC_DEFINE([HAVE_]AS_TR_CPP($1), 1)
    if test "${rb_cv_type_$1}" = yes; then
	m4_bmatch([$2], [^[1-9][0-9]*$], [AC_CHECK_SIZEOF([$1], 0, [AC_INCLUDES_DEFAULT([$4])])],
			[RUBY_CHECK_SIZEOF([$1], [$2], [], [AC_INCLUDES_DEFAULT([$4])])])
    else
	AC_DEFINE_UNQUOTED($1, [$rb_cv_type_$1])
	AC_DEFINE_UNQUOTED([SIZEOF_]AS_TR_CPP($1), [SIZEOF_]AS_TR_CPP([$type]))
    fi
    test -n "$cond" && echo "@%:@endif /* $cond */" >> confdefs.h
fi
AS_VAR_POPDEF([cond])dnl
AS_VAR_POPDEF([type])dnl
])

RUBY_DEFINT(int8_t, 1)
RUBY_DEFINT(uint8_t, 1, unsigned)
RUBY_DEFINT(int16_t, 2)
RUBY_DEFINT(uint16_t, 2, unsigned)
RUBY_DEFINT(int32_t, 4)
RUBY_DEFINT(uint32_t, 4, unsigned)
RUBY_DEFINT(int64_t, 8)
RUBY_DEFINT(uint64_t, 8, unsigned)
RUBY_DEFINT(int128_t, 16)
RUBY_DEFINT(uint128_t, 16, unsigned)
RUBY_DEFINT(intptr_t, void*)
RUBY_DEFINT(uintptr_t, void*, unsigned)
RUBY_DEFINT(ssize_t, size_t, [], [@%:@include <sys/types.h>])	dnl may differ from int, so not use AC_TYPE_SSIZE_T.

RUBY_NACL_CHECK_PEPPER_TYPES

AC_CACHE_CHECK(for stack end address, rb_cv_stack_end_address,
[rb_cv_stack_end_address=no
  AC_TRY_LINK(
    [extern void *__libc_stack_end;],
    [if (!__libc_stack_end) return 1;],
    [rb_cv_stack_end_address="__libc_stack_end"])
])
if test $rb_cv_stack_end_address != no; then
  AC_DEFINE_UNQUOTED(STACK_END_ADDRESS, $rb_cv_stack_end_address)
fi

# posix_memalign(memptr, alignment, size) implemented for OpenBSD 4.8 doesn't work if alignment > MALLOC_PAGESIZE.
# [ruby-core:42158] https://bugs.ruby-lang.org/issues/5901
# OpenBSD 5.2 fixed the problem. (src/lib/libc/stdlib/malloc.c:1.142)
# MirOS #10semel has the problem but fixed in the repository.  (src/lib/libc/stdlib/malloc.c:1.9)
AS_CASE(["$target_os"],
[openbsd*|mirbsd*], [
  AC_CACHE_CHECK(for heap align log on openbsd, rb_cv_page_size_log,
    [rb_cv_page_size_log=no
     for page_log in 12 13; do
       AC_TRY_RUN([
#include <math.h>
#include <unistd.h>

int
main() {
  if ((int)log2((double)sysconf(_SC_PAGESIZE)) != $page_log) return 1;
  return 0;
}
       ],
       rb_cv_page_size_log="$page_log"; break)
     done])
  if test $rb_cv_page_size_log != no; then
    AC_DEFINE_UNQUOTED(HEAP_ALIGN_LOG, $rb_cv_page_size_log)
  else
    AC_DEFINE_UNQUOTED(HEAP_ALIGN_LOG, 12)
  fi
])

dnl Checks for library functions.
AC_TYPE_GETGROUPS
AC_TYPE_SIGNAL
AS_CASE(["${target_cpu}-${target_os}:${target_archs}"],
[powerpc-darwin*], [
  AC_LIBSOURCES(alloca.c)
  AC_SUBST([ALLOCA], [\${LIBOBJDIR}alloca.${ac_objext}])
  AC_DEFINE(C_ALLOCA)
  AC_DEFINE_UNQUOTED(alloca, alloca)
  ],
[universal-darwin*:*ppc*], [
  AC_LIBSOURCES(alloca.c)
  AC_SUBST([ALLOCA], [\${LIBOBJDIR}alloca.${ac_objext}])
  RUBY_DEFINE_IF([defined __powerpc__], C_ALLOCA, 1)
  RUBY_DEFINE_IF([defined __powerpc__], alloca, alloca)
  ],
[
  AC_FUNC_ALLOCA
  ])
if test "x$ALLOCA" = "x"; then
    AC_CACHE_CHECK([for dynamic size alloca], rb_cv_dynamic_alloca, [
    for chk in ok __chkstk; do
	AC_TRY_LINK([
	    @%:@ifdef HAVE_ALLOCA_H
	    @%:@include <alloca.h>
	    @%:@endif
	    void $chk() {}
	    int dynamic_alloca_test;
	    int dynamic_alloca_result;],
	    [dynamic_alloca_result = alloca(dynamic_alloca_test) != 0;],
	    [rb_cv_dynamic_alloca=$chk; break])
    done])
    if test "x$rb_cv_dynamic_alloca" = "x__chkstk"; then
	AC_DEFINE_UNQUOTED(RUBY_ALLOCA_CHKSTK, _$rb_cv_dynamic_alloca)
	AS_CASE("$target_cpu",
	[x64|x86_64], [
	    AC_SUBST([ALLOCA], [\${LIBOBJDIR}x86_64-chkstk.${ac_objext}])
	],)
    fi
fi
AC_FUNC_MEMCMP

# http://sources.redhat.com/ml/libc-hacker/2005-08/msg00008.html
# Debian GNU/Linux Etch's libc6.1 2.3.6.ds1-13etch5 has this problem.
# Debian GNU/Linux Lenny's libc6.1 2.7-10 has no problem.
AC_CACHE_CHECK(for broken erfc of glibc-2.3.6 on IA64, rb_cv_broken_glibc_ia64_erfc,
  [AC_TRY_RUN([
#include <math.h>
int
main()
{
   erfc(10000.0);
   return 0;
}
],
	rb_cv_broken_glibc_ia64_erfc=no,
	rb_cv_broken_glibc_ia64_erfc=yes,
	rb_cv_broken_glibc_ia64_erfc=no)])
AS_CASE([$rb_cv_broken_glibc_ia64_erfc],[yes],[ac_cv_func_erf=no])

AS_CASE(["$target_os"],[freebsd*],[
	 AC_DEFINE(BROKEN_CLOSE)
	 AC_REPLACE_FUNCS(close)
	 ])

AC_REPLACE_FUNCS(acosh)
AC_REPLACE_FUNCS(cbrt)
AC_REPLACE_FUNCS(crypt)
AC_REPLACE_FUNCS(dup2)
AC_REPLACE_FUNCS(erf)
AC_REPLACE_FUNCS(explicit_bzero)
AC_REPLACE_FUNCS(ffs)
AC_REPLACE_FUNCS(finite)
AC_REPLACE_FUNCS(flock)
AC_REPLACE_FUNCS(hypot)
AC_REPLACE_FUNCS(isinf)
AC_REPLACE_FUNCS(isnan)
AC_REPLACE_FUNCS(lgamma_r)
AC_REPLACE_FUNCS(memmove)
AC_REPLACE_FUNCS(nextafter)
AC_REPLACE_FUNCS(setproctitle)
AC_REPLACE_FUNCS(strchr)
AC_REPLACE_FUNCS(strerror)
AC_REPLACE_FUNCS(strlcat)
AC_REPLACE_FUNCS(strlcpy)
AC_REPLACE_FUNCS(strstr)
AC_REPLACE_FUNCS(tgamma)

# for missing/setproctitle.c
AS_CASE(["$target_os"],
[aix* | k*bsd*-gnu | kopensolaris*-gnu | linux* | darwin*], [AC_DEFINE(SPT_TYPE,SPT_REUSEARGV)],
[hpux*], [AC_DEFINE(SPT_TYPE,SPT_PSTAT) ],
[])
AC_CHECK_HEADERS(sys/pstat.h)


AC_CACHE_CHECK(for signbit, rb_cv_have_signbit,
  [AC_TRY_LINK([
#include <math.h>
], [int v = signbit(-0.0);],
	rb_cv_have_signbit=yes,
	rb_cv_have_signbit=no)])
if test "$rb_cv_have_signbit" = yes; then
  AC_DEFINE(HAVE_SIGNBIT)
else
  AC_LIBOBJ([signbit])
fi

AC_CACHE_CHECK(for broken memmem, rb_cv_broken_memmem, [
    AC_TRY_RUN([
@%:@include <string.h>

int
main(int argc, char **argv)
{
    const char *str = "hogefugafoobar";
    const char *rs = "foo";
    const char *empty = "";
    char *p;

    p = memmem(str, strlen(str), rs, strlen(rs));
    if (p == str+8) {
	p = memmem(str, strlen(str), empty, strlen(empty));
	if (p == str)
	    return 0;
    }
    return 1;
}
    ],
    rb_cv_broken_memmem=no,
    rb_cv_broken_memmem=yes,
    rb_cv_broken_memmem=yes)
])
test x"$rb_cv_broken_memmem" = xyes && ac_cv_func_memmem=no

AC_FUNC_FORK

AC_CHECK_FUNCS(__syscall)
AC_CHECK_FUNCS(_longjmp)		# used for AC_ARG_WITH(setjmp-type)
# we don't use _setjmp if _longjmp doesn't exist.
test x$ac_cv_func__longjmp = xno && ac_cv_func__setjmp=no
AC_CHECK_FUNCS(arc4random_buf)
AC_CHECK_FUNCS(atan2l atan2f)
AC_CHECK_FUNCS(chroot)
AC_CHECK_FUNCS(chsize)
AC_CHECK_FUNCS(clock_gettime)
AC_CHECK_FUNCS(cosh)
AC_CHECK_FUNCS(crypt_r)
AC_CHECK_FUNCS(daemon)
AC_CHECK_FUNCS(dirfd)
AC_CHECK_FUNCS(dl_iterate_phdr)
AC_CHECK_FUNCS(dlopen)
AC_CHECK_FUNCS(dladdr)
AC_CHECK_FUNCS(dup)
AC_CHECK_FUNCS(dup3)
AC_CHECK_FUNCS(eaccess)
AC_CHECK_FUNCS(endgrent)
AC_CHECK_FUNCS(fchmod)
AC_CHECK_FUNCS(fchown)
AC_CHECK_FUNCS(fcntl)
AC_CHECK_FUNCS(fdatasync)
AC_CHECK_FUNCS(fgetattrlist)
AC_CHECK_FUNCS(fmod)
AC_CHECK_FUNCS(fsync)
AC_CHECK_FUNCS(ftruncate)
AC_CHECK_FUNCS(ftruncate64)		# used for Win32 platform
AC_CHECK_FUNCS(getattrlist)
AC_CHECK_FUNCS(getcwd)
AC_CHECK_FUNCS(getgidx)
AC_CHECK_FUNCS(getgrnam)
AC_CHECK_FUNCS(getgrnam_r)
AC_CHECK_FUNCS(getgroups)
AC_CHECK_FUNCS(getpgid)
AC_CHECK_FUNCS(getpgrp)
AC_CHECK_FUNCS(getpriority)
AC_CHECK_FUNCS(getpwnam_r)
AC_CHECK_FUNCS(getresgid)
AC_CHECK_FUNCS(getresuid)
AC_CHECK_FUNCS(getrlimit)
AC_CHECK_FUNCS(getsid)
AC_CHECK_FUNCS(gettimeofday)		# for making ac_cv_func_gettimeofday
AC_CHECK_FUNCS(getuidx)
AC_CHECK_FUNCS(gmtime_r)
AC_CHECK_FUNCS(initgroups)
AC_CHECK_FUNCS(ioctl)
AC_CHECK_FUNCS(isfinite)
AC_CHECK_FUNCS(issetugid)
AC_CHECK_FUNCS(killpg)
AC_CHECK_FUNCS(lchmod)
AC_CHECK_FUNCS(lchown)
AC_CHECK_FUNCS(link)
AC_CHECK_FUNCS(llabs)
AC_CHECK_FUNCS(lockf)
AC_CHECK_FUNCS(log2)
AC_CHECK_FUNCS(lstat)
AC_CHECK_FUNCS(malloc_usable_size)
AC_CHECK_FUNCS(malloc_size)
AC_CHECK_FUNCS(mblen)
AC_CHECK_FUNCS(memalign)
AC_CHECK_FUNCS(memset_s)
AC_CHECK_FUNCS(writev)
AC_CHECK_FUNCS(memrchr)
AC_CHECK_FUNCS(memmem)
AC_CHECK_FUNCS(mkfifo)
AC_CHECK_FUNCS(mknod)
AC_CHECK_FUNCS(mktime)
AC_CHECK_FUNCS(pipe2)
AC_CHECK_FUNCS(poll)
AC_CHECK_FUNCS(posix_fadvise)
AC_CHECK_FUNCS(posix_memalign)
AC_CHECK_FUNCS(ppoll)
AC_CHECK_FUNCS(pread)
AC_CHECK_FUNCS(qsort_r)
AC_CHECK_FUNCS(qsort_s)
AC_CHECK_FUNCS(readlink)
AC_CHECK_FUNCS(round)
AC_CHECK_FUNCS(sched_getaffinity)
AC_CHECK_FUNCS(seekdir)
AC_CHECK_FUNCS(select_large_fdset)
AC_CHECK_FUNCS(sendfile)
AC_CHECK_FUNCS(setegid)
AC_CHECK_FUNCS(setenv)
AC_CHECK_FUNCS(seteuid)
AC_CHECK_FUNCS(setgid)
AC_CHECK_FUNCS(setgroups)
AC_CHECK_FUNCS(setpgid)
AC_CHECK_FUNCS(setpgrp)
AC_CHECK_FUNCS(setregid)
AC_CHECK_FUNCS(setresgid)
AC_CHECK_FUNCS(setresuid)
AC_CHECK_FUNCS(setreuid)
AC_CHECK_FUNCS(setrgid)
AC_CHECK_FUNCS(setrlimit)
AC_CHECK_FUNCS(setruid)
AC_CHECK_FUNCS(setsid)
AC_CHECK_FUNCS(setuid)
AC_CHECK_FUNCS(shutdown)
AC_CHECK_FUNCS(sigaction)
AC_CHECK_FUNCS(sigaltstack)
AC_CHECK_FUNCS(sigprocmask)
AC_CHECK_FUNCS(sinh)
AC_CHECK_FUNCS(spawnv)
AC_CHECK_FUNCS(symlink)
AC_CHECK_FUNCS(syscall)
AC_CHECK_FUNCS(sysconf)
AC_CHECK_FUNCS(tanh)
AC_CHECK_FUNCS(telldir)
AC_CHECK_FUNCS(timegm)
AC_CHECK_FUNCS(times)
AC_CHECK_FUNCS(truncate)
AC_CHECK_FUNCS(truncate64)		# used for Win32
AC_CHECK_FUNCS(unsetenv)
AC_CHECK_FUNCS(utimensat)
AC_CHECK_FUNCS(utimes)
AC_CHECK_FUNCS(wait4)
AC_CHECK_FUNCS(waitpid)

AS_IF([test "$ac_cv_func_memset_s" = yes],
    [RUBY_DEFINE_IF([!defined __STDC_WANT_LIB_EXT1__], [__STDC_WANT_LIB_EXT1__], 1)])

AS_IF([test "$ac_cv_func_getcwd" = yes], [
    AC_CACHE_CHECK(if getcwd allocates buffer if NULL is given, [rb_cv_getcwd_malloc],
	[AC_TRY_RUN([
@%:@include <stddef.h>
@%:@include <stdio.h>
@%:@ifdef HAVE_UNISTD_H
@%:@include <unistd.h>
@%:@endif
@%:@ifndef EXIT_SUCCESS
@%:@define EXIT_SUCCESS 0
@%:@endif
@%:@ifndef EXIT_FAILURE
@%:@define EXIT_FAILURE 1
@%:@endif

int
main(int argc, char **argv)
{
    if (!getcwd(NULL, 0)) return EXIT_FAILURE;
    return EXIT_SUCCESS;
}
],
	    rb_cv_getcwd_malloc=yes,
	    rb_cv_getcwd_malloc=no,
	    AS_CASE($target_os,
		[linux*|darwin*|*bsd|cygwin*|mingw*|mswin*],
		[rb_cv_getcwd_malloc=yes],
		[rb_cv_getcwd_malloc=no]))])
    AS_IF([test "$rb_cv_getcwd_malloc" = no], [AC_DEFINE(NO_GETCWD_MALLOC, 1)])
])

AS_IF([test "$ac_cv_func_crypt_r" = yes],
    [AC_CHECK_HEADERS(crypt.h)])
AS_IF([test "$ac_cv_func_crypt_r:$ac_cv_header_crypt_h" = yes:yes],
    [AC_CHECK_MEMBERS([struct crypt_data.initialized], [], [],
		      [AC_INCLUDES_DEFAULT([@%:@include <crypt.h>])])])

AC_DEFUN([RUBY_CHECK_BUILTIN_FUNC], [dnl
AC_CACHE_CHECK([for $1], AS_TR_SH(rb_cv_builtin_$1),
  [AC_LINK_IFELSE(
    [AC_LANG_PROGRAM([int foo;], [$2;])],
    [AS_TR_SH(rb_cv_builtin_$1)=yes],
    [AS_TR_SH(rb_cv_builtin_$1)=no])])
if test "${AS_TR_SH(rb_cv_builtin_$1)}" != no; then
  AC_DEFINE(AS_TR_CPP(HAVE_BUILTIN_$1))
fi])
RUBY_CHECK_BUILTIN_FUNC(__builtin_bswap16, [__builtin_bswap16(0)])
RUBY_CHECK_BUILTIN_FUNC(__builtin_bswap32, [__builtin_bswap32(0)])
RUBY_CHECK_BUILTIN_FUNC(__builtin_bswap64, [__builtin_bswap64(0)])
RUBY_CHECK_BUILTIN_FUNC(__builtin_popcount, [__builtin_popcount(0)])
RUBY_CHECK_BUILTIN_FUNC(__builtin_popcountll, [__builtin_popcountll(0)])
RUBY_CHECK_BUILTIN_FUNC(__builtin_clz, [__builtin_clz(0)])
RUBY_CHECK_BUILTIN_FUNC(__builtin_clzl, [__builtin_clzl(0)])
RUBY_CHECK_BUILTIN_FUNC(__builtin_clzll, [__builtin_clzll(0)])
RUBY_CHECK_BUILTIN_FUNC(__builtin_ctz, [__builtin_ctz(0)])
RUBY_CHECK_BUILTIN_FUNC(__builtin_ctzll, [__builtin_ctzll(0)])
RUBY_CHECK_BUILTIN_FUNC(__builtin_constant_p, [__builtin_constant_p(0)])
RUBY_CHECK_BUILTIN_FUNC(__builtin_choose_expr, [
    [int x[__extension__(__builtin_choose_expr(1, 1, -1))]];
    [int y[__extension__(__builtin_choose_expr(0, -1, 1))]];
    ])
if test x$rb_cv_builtin___builtin_choose_expr = xyes; then
    RUBY_CHECK_BUILTIN_FUNC(__builtin_choose_expr_constant_p, [
    [int x[__extension__(__builtin_choose_expr(__builtin_constant_p(1), 1, -1))]];
    [int y[__extension__(__builtin_choose_expr(__builtin_constant_p(foo), -1, 1))]];
    ])
fi
RUBY_CHECK_BUILTIN_FUNC(__builtin_types_compatible_p, [__builtin_types_compatible_p(int, int)])

if test "$ac_cv_func_qsort_r" != no; then
  AC_CACHE_CHECK(whether qsort_r is GNU version, rb_cv_gnu_qsort_r,
    [AC_TRY_COMPILE([
@%:@include <stdlib.h>
void qsort_r(void *base, size_t nmemb, size_t size,
	    int (*compar)(const void *, const void *, void *),
	    void *arg);
],[ ],
      [rb_cv_gnu_qsort_r=yes],
      [rb_cv_gnu_qsort_r=no])
  ])
  AC_CACHE_CHECK(whether qsort_r is BSD version, rb_cv_bsd_qsort_r,
    [AC_TRY_COMPILE([
@%:@include <stdlib.h>
void qsort_r(void *base, size_t nmemb, size_t size,
	     void *arg, int (*compar)(void *, const void *, const void *));
],[ ],
      [rb_cv_bsd_qsort_r=yes],
      [rb_cv_bsd_qsort_r=no])
  ])
  AS_CASE("$rb_cv_gnu_qsort_r:$rb_cv_bsd_qsort_r",
  [yes:no], [
    AC_DEFINE(HAVE_GNU_QSORT_R, 1)
  ],
  [no:yes], [
    AC_DEFINE(HAVE_BSD_QSORT_R, 1)
  ])
fi

AC_CACHE_CHECK(whether atan2 handles Inf as C99, rb_cv_atan2_inf_c99, [
    AS_IF([test $ac_cv_func_atan2f:$ac_cv_func_atan2l = yes:yes], [
	AC_TRY_RUN([
@%:@include <math.h>
@%:@ifdef HAVE_UNISTD_H
@%:@include <unistd.h>
@%:@endif
@%:@ifndef EXIT_SUCCESS
@%:@define EXIT_SUCCESS 0
@%:@endif
@%:@ifndef EXIT_FAILURE
@%:@define EXIT_FAILURE 1
@%:@endif

int
main(int argc, char **argv)
{
    if (fabs(atan2(INFINITY, INFINITY) - M_PI_4) <= 0.01) return EXIT_SUCCESS;
    return EXIT_FAILURE;
}
],
	[rb_cv_atan2_inf_c99=yes],
	[rb_cv_atan2_inf_c99=no],
	[AS_CASE($target_os, [mingw*|mswin*], [rb_cv_atan2_inf_c99=no], [rb_cv_atan2_inf_c99=yes])]
	)
    ], [rb_cv_atan2_inf_c99=no])
])
AS_IF([test "x$rb_cv_atan2_inf_c99" = xyes], [AC_DEFINE(ATAN2_INF_C99)])

AS_IF([test "x$ac_cv_func_lgamma_r" = xyes], [
    AC_CACHE_CHECK(whether lgamma_r handles +0.0 and -0.0, rb_cv_lgamma_r_pm0, [
	AC_TRY_RUN([
@%:@include <math.h>
@%:@ifdef HAVE_UNISTD_H
@%:@include <unistd.h>
@%:@endif
@%:@ifndef EXIT_SUCCESS
@%:@define EXIT_SUCCESS 0
@%:@endif
@%:@ifndef EXIT_FAILURE
@%:@define EXIT_FAILURE 1
@%:@endif

int
main(int argc, char **argv)
{
    int sign = 0;
    double x = lgamma_r(-0.0, &sign);

    /* should be [+inf, -1] */
    if (x <= 0) return EXIT_FAILURE;
    if (!isinf(x)) return EXIT_FAILURE;
    if (sign != -1) return EXIT_FAILURE;

    /* should be [+inf, 1] */
    x = lgamma_r(+0.0, &sign);
    if (x <= 0) return EXIT_FAILURE;
    if (!isinf(x)) return EXIT_FAILURE;
    if (sign != 1) return EXIT_FAILURE;
    return EXIT_SUCCESS;
}
],
	[rb_cv_lgamma_r_pm0=yes],
	[rb_cv_lgamma_r_pm0=no],
	[rb_cv_lgamma_r_pm0=yes]
	)
    ])
    AS_IF([test "x$rb_cv_lgamma_r_pm0" = xno], [AC_DEFINE(LGAMMA_R_PM0_FIX)])
])

# Some platform need -lrt for clock_gettime, but the other don't.
if test x"$ac_cv_func_clock_gettime" != xyes; then
    # glibc 2.17 moves clock_* functions from librt to the main C library.
    # http://sourceware.org/ml/libc-announce/2012/msg00001.html
    AC_CHECK_LIB(rt, clock_gettime)
    if test x"$ac_cv_lib_rt_clock_gettime" = xyes; then
	AC_DEFINE(HAVE_CLOCK_GETTIME, 1)
    fi
fi
AC_CHECK_FUNCS(clock_getres) # clock_getres should be tested after clock_gettime test including librt test.

AC_CACHE_CHECK(for unsetenv returns a value, rb_cv_unsetenv_return_value,
  [AC_TRY_COMPILE([
#include <stdlib.h>
], [int v = unsetenv("foo");],
	rb_cv_unsetenv_return_value=yes,
	rb_cv_unsetenv_return_value=no)])
if test "$rb_cv_unsetenv_return_value" = no; then
  AC_DEFINE(VOID_UNSETENV)
fi

# used for AC_ARG_WITH(setjmp-type)
AC_DEFUN([RUBY_CHECK_SETJMP], [
AC_CACHE_CHECK([for ]$1[ as a macro or function], ac_cv_func_$1,
  [AC_TRY_COMPILE([
@%:@include <setjmp.h>
]AC_INCLUDES_DEFAULT([$3])[
@%:@define JMPARGS_1 env
@%:@define JMPARGS_2 env,1
@%:@define JMPARGS JMPARGS_]m4_ifval($2,2,1)[
],
    m4_ifval($2,$2,jmp_buf)[ env; $1(JMPARGS);],
    ac_cv_func_$1=yes,
    ac_cv_func_$1=no)]
)
AS_IF([test "$ac_cv_func_]$1[" = yes], [AC_DEFINE([HAVE_]AS_TR_CPP($1), 1)])
])

AC_DEFUN([RUBY_CHECK_BUILTIN_SETJMP], [
if test x"${ac_cv_func___builtin_setjmp}" = xyes; then
   unset ac_cv_func___builtin_setjmp
fi
AC_CACHE_CHECK(for __builtin_setjmp, ac_cv_func___builtin_setjmp,
    [
    ac_cv_func___builtin_setjmp=no
    for cast in "" "(void **)"; do
	RUBY_WERROR_FLAG(
	[AC_TRY_LINK([@%:@include <setjmp.h>
	    @%:@include <stdio.h>
	    jmp_buf jb;
	    @%:@ifdef NORETURN
	    NORETURN(void t(void));
	    @%:@endif
	    void t(void) {__builtin_longjmp($cast jb, 1);}
	    int jump(void) {(void)(__builtin_setjmp($cast jb) ? 1 : 0); return 0;}],
	    [
	    void (*volatile f)(void) = t;
	    if (!jump()) printf("%d\n", f != 0);
	    ],
	    [ac_cv_func___builtin_setjmp="yes with cast ($cast)"])
	])
	test "$ac_cv_func___builtin_setjmp" = no || break
    done])
])

AC_DEFUN([RUBY_SETJMP_TYPE], [
RUBY_CHECK_BUILTIN_SETJMP
RUBY_CHECK_SETJMP(_setjmpex, [], [@%:@include <setjmpex.h>])
RUBY_CHECK_SETJMP(_setjmp)
RUBY_CHECK_SETJMP(sigsetjmp, [sigjmp_buf])
AC_MSG_CHECKING(for setjmp type)
setjmp_suffix=
AC_ARG_WITH(setjmp-type,
	AS_HELP_STRING([--with-setjmp-type], [select setjmp type]),
	[
	AS_CASE([$withval],
	[__builtin_setjmp], [setjmp=__builtin_setjmp],
	[_setjmp], [ setjmp_prefix=_],
	[sigsetjmp], [ setjmp_prefix=sig],
	[setjmp], [ setjmp_prefix=],
	[setjmpex], [ setjmp_prefix= setjmp_suffix=ex],
	[''], [ unset setjmp_prefix],
	[   AC_MSG_ERROR(invalid setjmp type: $withval)])], [unset setjmp_prefix])
setjmp_cast=
if test ${setjmp_prefix+set}; then
    if test "${setjmp_prefix}" && eval test '$ac_cv_func_'${setjmp_prefix}setjmp${setjmp_suffix} = no; then
	AC_MSG_ERROR(${setjmp_prefix}setjmp${setjmp_suffix} is not available)
    fi
elif { AS_CASE("$ac_cv_func___builtin_setjmp", [yes*], [true], [false]) }; then
    setjmp_cast=`expr "$ac_cv_func___builtin_setjmp" : "yes with cast (\(.*\))"`
    setjmp_prefix=__builtin_
    setjmp_suffix=
elif test "$ac_cv_header_setjmpex_h:$ac_cv_func__setjmpex" = yes:yes; then
    setjmp_prefix=
    setjmp_suffix=ex
elif test "$ac_cv_func__setjmp" = yes; then
    setjmp_prefix=_
    setjmp_suffix=
elif test "$ac_cv_func_sigsetjmp" = yes; then
    AS_CASE([$target_os],[solaris*|cygwin*],[setjmp_prefix=],[setjmp_prefix=sig])
    setjmp_suffix=
else
    setjmp_prefix=
    setjmp_suffix=
fi
if test x$setjmp_prefix = xsig; then
    setjmp_sigmask=yes
else
    unset setjmp_sigmask
fi
AC_MSG_RESULT(${setjmp_prefix}setjmp${setjmp_suffix}${setjmp_cast:+\($setjmp_cast\)})
AC_DEFINE_UNQUOTED([RUBY_SETJMP(env)], [${setjmp_prefix}setjmp${setjmp_suffix}($setjmp_cast(env)${setjmp_sigmask+,0})])
AC_DEFINE_UNQUOTED([RUBY_LONGJMP(env,val)], [${setjmp_prefix}longjmp($setjmp_cast(env),val)])
AC_DEFINE_UNQUOTED(RUBY_JMP_BUF, ${setjmp_sigmask+${setjmp_prefix}}jmp_buf)
AS_IF([test x$setjmp_suffix = xex], [AC_DEFINE_UNQUOTED(RUBY_USE_SETJMPEX, 1)])
])
# End of setjmp check.

AC_ARG_ENABLE(setreuid,
       AS_HELP_STRING([--enable-setreuid], [use setreuid()/setregid() according to need even if obsolete]),
       [use_setreuid=$enableval])
if test "$use_setreuid" = yes; then
    AC_DEFINE(USE_SETREUID)
    AC_DEFINE(USE_SETREGID)
fi
AC_STRUCT_TIMEZONE
AC_CACHE_CHECK(for struct tm.tm_gmtoff, rb_cv_member_struct_tm_tm_gmtoff,
  [AC_TRY_COMPILE([
@%:@define _BSD_SOURCE
@%:@define _DEFAULT_SOURCE
@%:@include <time.h>
   ],
    [struct tm t; t.tm_gmtoff = 3600;],
  [rb_cv_member_struct_tm_tm_gmtoff=yes],
  [rb_cv_member_struct_tm_tm_gmtoff=no])])
if test "$rb_cv_member_struct_tm_tm_gmtoff" = yes; then
  AC_DEFINE(HAVE_STRUCT_TM_TM_GMTOFF)
fi
AC_CACHE_CHECK(for external int daylight, rb_cv_have_daylight,
  [AC_TRY_LINK([#include <time.h>
  int i;],
	[i = daylight;],
	rb_cv_have_daylight=yes,
	rb_cv_have_daylight=no)])
if test "$rb_cv_have_daylight" = yes; then
  AC_DEFINE(HAVE_DAYLIGHT)
fi
AC_DEFUN([RUBY_CHECK_VARTYPE], [dnl
AC_CACHE_CHECK([for external $1], AS_TR_SH(rb_cv_var_$1),
  [AS_TR_SH(rb_cv_var_$1)=no
  AC_TRY_COMPILE([
#ifndef _XOPEN_SOURCE
#define _XOPEN_SOURCE 1
#endif
$2
;
const volatile void *volatile t;],
    [t = &(&$1)[0];],
    [for t in $3; do
      AC_TRY_COMPILE([
#ifndef _XOPEN_SOURCE
#define _XOPEN_SOURCE 1
#endif
$2
;
extern $t $1;
const volatile void *volatile t;],
        [t = &(&$1)[0];],
        [AS_TR_SH(rb_cv_var_$1)=$t; break])
    done])])
if test "${AS_TR_SH(rb_cv_var_$1)}" != no; then
  AC_DEFINE(AS_TR_CPP(HAVE_VAR_$1))
  AC_DEFINE_UNQUOTED(AS_TR_CPP(TYPEOF_VAR_$1), ${AS_TR_SH(rb_cv_var_$1)})
fi])
RUBY_CHECK_VARTYPE(timezone, [@%:@include <time.h>], [long int])
RUBY_CHECK_VARTYPE(altzone, [@%:@include <time.h>], [long int])
AC_CHECK_FUNCS(timezone)
if test "$ac_cv_func_timezone" = yes; then
  AC_CACHE_CHECK([whether timezone requires zero arguments], rb_cv_func_timezone_void,
    [AC_TRY_COMPILE([@%:@include <time.h>],
      [(void)timezone(0, 0);],
      [rb_cv_func_timezone_void=no],
      [rb_cv_func_timezone_void=yes])]
  )
  if test $rb_cv_func_timezone_void = yes; then
    AC_DEFINE(TIMEZONE_VOID)
  fi
fi

AC_CACHE_CHECK(for negative time_t for gmtime(3), rb_cv_negative_time_t,
  [AC_TRY_RUN([
#include <stdlib.h>
#include <time.h>

void
check(tm, y, m, d, h, s)
    struct tm *tm;
    int y, m, d, h, s;
{
    if (!tm ||
	tm->tm_year != y ||
	tm->tm_mon  != m-1 ||
	tm->tm_mday != d ||
	tm->tm_hour != h ||
	tm->tm_sec  != s) {
	exit(1);
    }
}

int
main()
{
   time_t t = -1;
   struct tm *tm;

   check(gmtime(&t), 69, 12, 31, 23, 59);
   t = ~(time_t)0 << 31;
   check(gmtime(&t), 1, 12, 13, 20, 52);
   return 0;
}
],
	rb_cv_negative_time_t=yes,
	rb_cv_negative_time_t=no,
	rb_cv_negative_time_t=yes)])
if test "$rb_cv_negative_time_t" = yes; then
  AC_DEFINE(NEGATIVE_TIME_T)
fi

# [ruby-dev:40910] overflow of time on FreeBSD
# http://www.freebsd.org/cgi/query-pr.cgi?pr=145341
AC_CACHE_CHECK(for localtime(3) overflow correctly, rb_cv_localtime_overflow,
  [AC_TRY_RUN([
#include <stdlib.h>
#include <time.h>

void
check(time_t t1)
{
    struct tm *tm;
    time_t t2;
    tm = localtime(&t1);
    if (!tm)
	return; /* overflow detected.  ok. */
    t2 = mktime(tm);
    if (t1 == t2)
        return; /* round-trip.  ok. */
    exit(1);
}

int
main()
{
    time_t t;
    if (~(time_t)0 <= 0) {
        t = (((time_t)1) << (sizeof(time_t) * 8 - 2));
        t |= t - 1;
    }
    else {
        t = ~(time_t)0;
    }
    check(t);
    return 0;
}
],
	rb_cv_localtime_overflow=yes,
	rb_cv_localtime_overflow=no,
	rb_cv_localtime_overflow=no)])
if test "$rb_cv_localtime_overflow" = no; then
  AC_DEFINE(LOCALTIME_OVERFLOW_PROBLEM)
fi

if test "$ac_cv_func_sigprocmask" = yes && test "$ac_cv_func_sigaction" = yes; then
   AC_DEFINE(POSIX_SIGNAL)
else
  AC_CHECK_FUNCS(sigsetmask)
  AC_CACHE_CHECK(for BSD signal semantics, rb_cv_bsd_signal,
    [AC_TRY_RUN([
#include <stdio.h>
#include <signal.h>

void
sig_handler(dummy)
     int dummy;
{
}

int
main()
{
  signal(SIGINT, sig_handler);
  kill(getpid(), SIGINT);
  kill(getpid(), SIGINT);
  return 0;
}
],
	rb_cv_bsd_signal=yes,
	rb_cv_bsd_signal=no,
	rb_cv_bsd_signal=$ac_cv_func_sigsetmask)])
  if test "$rb_cv_bsd_signal" = yes; then
    AC_DEFINE(BSD_SIGNAL)
  fi
fi

AC_CHECK_TYPES([sig_t],[],[],[@%:@include <signal.h>])

if test "$ac_cv_func_getpgid" = no; then
  # AC_FUNC_GETPGRP fails when cross-compiling with old autoconf.
  # autoconf is changed between 2.52d and 2.52f?
  # http://lists.gnu.org/archive/html/bug-gnu-utils/2001-09/msg00181.html
  # "autoconf cleanup for AC_FUNC_GETPGRP and GETPGRP_VOID"
AC_FUNC_GETPGRP
fi
if test "$ac_cv_func_setpgid:$ac_cv_func_setpgrp" = no:yes; then
  # AC_FUNC_SETPGRP fails when cross-compiling.  (until autoconf 2.69?)
  # https://lists.gnu.org/archive/html/bug-autoconf/2013-02/msg00002.html
  # "AC_FUNC_SETPGRP fails to work properly when cross-compiling"
AC_FUNC_SETPGRP
fi

if test x"$ac_cv_func_dirfd" = xno; then
  AS_CASE(["$target_os"],[solaris*],
          [AC_CHECK_MEMBERS([DIR.d_fd, DIR.dd_fd],,,[
#include <sys/types.h>
#include <dirent.h>
])])
fi

if test x"$target_cpu" = xia64; then
    AC_LIBOBJ([ia64])
    AC_CACHE_CHECK(for __libc_ia64_register_backing_store_base,
                   rb_cv___libc_ia64_register_backing_store_base,
    [rb_cv___libc_ia64_register_backing_store_base=no
    AC_TRY_LINK(
      [extern unsigned long __libc_ia64_register_backing_store_base;],
      [unsigned long p = __libc_ia64_register_backing_store_base;
       printf("%ld\n", p);],
      [rb_cv___libc_ia64_register_backing_store_base=yes])])
    if test $rb_cv___libc_ia64_register_backing_store_base = yes; then
      AC_DEFINE(HAVE___LIBC_IA64_REGISTER_BACKING_STORE_BASE)
    fi
fi

AC_CACHE_CHECK(whether right shift preserve sign bit, rb_cv_rshift_sign,
    [AC_COMPILE_IFELSE([AC_LANG_BOOL_COMPILE_TRY([], [(-1==(-1>>1))])],
	rb_cv_rshift_sign=yes,
	rb_cv_rshift_sign=no)])
if test "$rb_cv_rshift_sign" = yes; then
  AC_DEFINE(RSHIFT(x,y), ((x)>>(int)(y)))
else
  AC_DEFINE(RSHIFT(x,y), (((x)<0) ? ~((~(x))>>(int)(y)) : (x)>>(int)(y)))
fi

if test x"$ac_cv_func_gettimeofday" != xyes; then
    AC_MSG_ERROR(gettimeofday() must exist)
fi

if test "$ac_cv_func_sysconf" = yes; then
  AC_DEFUN([RUBY_CHECK_SYSCONF], [dnl
  AC_CACHE_CHECK([whether _SC_$1 is supported], rb_cv_have_sc_[]m4_tolower($1),
    [AC_TRY_COMPILE([#include <unistd.h>
      ],
      [_SC_$1 >= 0],
      rb_cv_have_sc_[]m4_tolower($1)=yes,
      rb_cv_have_sc_[]m4_tolower($1)=no)
    ])
  if test "$rb_cv_have_sc_[]m4_tolower($1)" = yes; then
    AC_DEFINE(HAVE__SC_$1)
  fi
  ])
  RUBY_CHECK_SYSCONF(CLK_TCK)
fi

AC_DEFUN([RUBY_STACK_GROW_DIRECTION], [
    AS_VAR_PUSHDEF([stack_grow_dir], [rb_cv_stack_grow_dir_$1])
    AC_CACHE_CHECK(stack growing direction on $1, stack_grow_dir, [
AS_CASE(["$1"],
[m68*|x86*|x64|i?86|ia64|ppc*|sparc*|alpha*], [ $2=-1],
[hppa*], [ $2=+1],
[
  AC_TRY_RUN([
/* recurse to get rid of inlining */
static int
stack_growup_p(addr, n)
    volatile int *addr, n;
{
    volatile int end;
    if (n > 0)
	return *addr = stack_growup_p(addr, n - 1);
    else
	return (&end > addr);
}
int main()
{
    int x;
    return stack_growup_p(&x, 10);
}
], $2=-1, $2=+1, $2=0)
  ])
eval stack_grow_dir=\$$2])
eval $2=\$stack_grow_dir
AS_VAR_POPDEF([stack_grow_dir])])
if test "${universal_binary-no}" = yes ; then
    archflagpat=`eval echo '"'"${ARCH_FLAG}"'"' | sed 's/[[][|.*]]/\\&/g'`
    save_CFLAGS="$CFLAGS" new_cflags=`echo "$CFLAGS" | sed "s|$archflagpat"'||'`
    save_LDFLAGS="$LDFLAGS" new_ldflags=`echo "$LDFLAGS" | sed "s|$archflagpat"'||'`
    stack_dir=
    for archs in ${universal_archnames}; do
	archs=`echo $archs | sed 's/=.*//'`
	CFLAGS="$new_cflags -arch $archs"
	LDFLAGS="$new_ldflags -arch $archs"
	RUBY_STACK_GROW_DIRECTION($archs, dir)
	if test x$stack_dir = x; then
	    stack_dir=$dir
	elif test x$stack_dir != x$dir; then
	    stack_dir=no
	fi
    done
    CFLAGS="$save_CFLAGS" LDFLAGS="$save_LDFLAGS"
    if test x$stack_dir = xno; then
	for archs in ${universal_archnames}; do
	    archs=`echo $archs | sed 's/=.*//'`
	    eval dir=\$[rb_cv_stack_grow_dir_]AS_TR_SH([$archs])
	    RUBY_DEFINE_IF([defined __${archs}__], STACK_GROW_DIRECTION, $dir)
	done
    else
	AC_DEFINE_UNQUOTED(STACK_GROW_DIRECTION, $stack_dir)
    fi
else
    RUBY_STACK_GROW_DIRECTION($target_cpu, dir)
    AC_DEFINE_UNQUOTED(STACK_GROW_DIRECTION, $dir)
fi

if test x"$enable_pthread" = xyes; then
    for pthread_lib in thr pthread pthreads c c_r root; do
	AC_CHECK_LIB($pthread_lib, pthread_kill,
		     rb_with_pthread=yes, rb_with_pthread=no)
	if test "$rb_with_pthread" = "yes"; then break; fi
    done
    if test x"$rb_with_pthread" = xyes; then
	AC_DEFINE(_REENTRANT)
	AC_DEFINE(_THREAD_SAFE)
	AC_DEFINE(HAVE_LIBPTHREAD)
	AC_CHECK_HEADERS(pthread_np.h, [], [], [@%:@include <pthread.h>])
	AS_CASE([$pthread_lib],
	[c],    [],
	[root], [],
	[c_r],  [MAINLIBS="-pthread $MAINLIBS"],
	        [AS_CASE(["$target_os"],
		    [openbsd*|mirbsd*], [LIBS="-pthread $LIBS"],
		    [LIBS="-l$pthread_lib $LIBS"])])
    else
	AC_MSG_WARN("Don't know how to find pthread library on your system -- thread support disabled")
    fi
    AC_CACHE_CHECK([whether pthread_t is scalar type], [rb_cv_scalar_pthread_t], [
	AC_TRY_COMPILE([
	    @%:@include <pthread.h>
	    ], [
	    pthread_t thread_id;
	    thread_id = 0;
	    if (!thread_id) return 0;
	    ], [rb_cv_scalar_pthread_t=yes], [rb_cv_scalar_pthread_t=no])
    ])
    if test x"$rb_cv_scalar_pthread_t" = xyes; then
	: # RUBY_CHECK_SIZEOF(pthread_t, [void* int long], [], [@%:@include <pthread.h>])
    else
	AC_DEFINE(NON_SCALAR_THREAD_ID)
    fi
    AC_CHECK_FUNCS(sched_yield pthread_attr_setinheritsched \
	pthread_attr_get_np pthread_attr_getstack\
	pthread_get_stackaddr_np pthread_get_stacksize_np \
	thr_stksegment pthread_stackseg_np pthread_getthrds_np \
	pthread_cond_init pthread_condattr_setclock pthread_condattr_init \
	pthread_sigmask pthread_setname_np pthread_set_name_np)
    AS_CASE(["$target_os"],[aix*],[ac_cv_func_pthread_getattr_np=no],[AC_CHECK_FUNCS(pthread_getattr_np)])
    if test "${host_os}" = "nacl"; then
      ac_cv_func_pthread_attr_init=no
    else
      AC_CHECK_FUNCS(pthread_attr_init)
    fi
    set_current_thread_name=
    if test "$ac_cv_func_pthread_setname_np" = yes; then
	AC_CACHE_CHECK([arguments of pthread_setname_np], [rb_cv_func_pthread_setname_np_arguments],
	    [rb_cv_func_pthread_setname_np_arguments=
	    # Linux,AIX,  (pthread_self(), name)
	    # NetBSD (pthread_self(), name, \"%s\")
	    # Darwin (name)
	    for mac in \
		"(pthread_self(), name)" \
		"(pthread_self(), name, \"%s\")" \
		"(name)" \
		; do
		AC_TRY_COMPILE([
		    @%:@include <pthread.h>
		    @%:@ifdef HAVE_PTHREAD_NP_H
		    @%:@include <pthread_np.h>
		    @%:@endif
		    @%:@define SET_THREAD_NAME(name) pthread_setname_np${mac}
		    ],
		    [if (SET_THREAD_NAME("conftest")) return 1;],
		    [rb_cv_func_pthread_setname_np_arguments="${mac}"
		    break])
	    done
	    ]
	)
	if test -n "${rb_cv_func_pthread_setname_np_arguments}"; then
	    set_current_thread_name="pthread_setname_np${rb_cv_func_pthread_setname_np_arguments}"
	fi
    elif test "$ac_cv_func_pthread_set_name_np" = yes; then
	set_current_thread_name="pthread_set_name_np(pthread_self(), name)"
    fi
    AS_IF([test -n "$set_current_thread_name"], [
	AC_DEFINE_UNQUOTED(SET_CURRENT_THREAD_NAME(name), $set_current_thread_name)
	AS_CASE([$set_current_thread_name],
	    [*'pthread_self()'*], [
		set_another_thread_name=`echo "$set_current_thread_name" | sed 's/pthread_self()/thid/'`
		AC_DEFINE_UNQUOTED(SET_ANOTHER_THREAD_NAME(thid,name), $set_another_thread_name)
	    ])
    ])
fi

if test x"$ac_cv_header_ucontext_h" = xno; then
    AC_CACHE_CHECK([if signal.h defines ucontext_t], [rb_cv_ucontext_in_signal_h],
	[AC_TRY_COMPILE([@%:@include <signal.h>],
	[size_t size = sizeof(ucontext_t);],
	[rb_cv_ucontext_in_signal_h=yes], [rb_cv_ucontext_in_signal_h=no])])
    if test x"$rb_cv_ucontext_in_signal_h" = xyes; then
	    AC_DEFINE_UNQUOTED(UCONTEXT_IN_SIGNAL_H, 1)
    fi
fi
if test x"$ac_cv_header_ucontext_h" = xyes -o x"$rb_cv_ucontext_in_signal_h" = xyes; then
    AC_CACHE_CHECK([if mcontext_t is a pointer], [rb_cv_mcontext_t_ptr],
	[AC_TRY_COMPILE([
	    @%:@include <signal.h>
	    @%:@ifdef HAVE_UCONTEXT_H
	    @%:@include <ucontext.h>
	    @%:@endif
        mcontext_t test(mcontext_t mc) {return mc+1;}
	],
	[test(0);],
	[rb_cv_mcontext_t_ptr=yes], [rb_cv_mcontext_t_ptr=no])])
    if test x"$rb_cv_mcontext_t_ptr" = xyes; then
	AC_DEFINE_UNQUOTED(DEFINE_MCONTEXT_PTR(mc, uc), mcontext_t mc = (uc)->uc_mcontext)
    else
	AC_DEFINE_UNQUOTED(DEFINE_MCONTEXT_PTR(mc, uc), mcontext_t *mc = &(uc)->uc_mcontext)
    fi
    if test x"$rb_with_pthread" = xyes; then
	AC_CHECK_FUNCS(getcontext setcontext)
    fi
fi

if test "$ac_cv_func_fork_works" = "yes" -a "$rb_with_pthread" = "yes"; then
    AC_CACHE_CHECK([if fork works with pthread], rb_cv_fork_with_pthread,
	[AC_TRY_RUN([
#include <stdlib.h>
#include <unistd.h>
#include <pthread.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <signal.h>
#ifndef EXIT_SUCCESS
#define EXIT_SUCCESS 0
#endif
#ifndef EXIT_FAILURE
#define EXIT_FAILURE 1
#endif

void *
thread_func(void *dmy)
{
    return dmy;
}

int
use_threads(void)
{
    pthread_t tid;
    if (pthread_create(&tid, 0, thread_func, 0) != 0) {
	return -1;
    }
    if (pthread_join(tid, 0) != 0) {
	return -1;
    }
    return 0;
}

int
main(int argc, char *argv[])
{
    pid_t pid;
    if (use_threads()) return EXIT_FAILURE;
    pid = fork();

    if (pid) {
	int loc;
	sleep(1);
	if (waitpid(pid, &loc, WNOHANG) == 0) {
	    kill(pid, SIGKILL);
	    return EXIT_FAILURE;
	}
        if (!WIFEXITED(loc) || WEXITSTATUS(loc) != EXIT_SUCCESS)
           return EXIT_FAILURE;
    }
    else {
	if (use_threads()) return EXIT_FAILURE;
    }

    return EXIT_SUCCESS;
}],
	rb_cv_fork_with_pthread=yes,
	rb_cv_fork_with_pthread=no,
	rb_cv_fork_with_pthread=yes)])
    test x$rb_cv_fork_with_pthread = xyes || AC_DEFINE(CANNOT_FORK_WITH_PTHREAD)
fi


}
{ # runtime section

dnl wheather use dln_a_out or not
AC_ARG_WITH(dln-a-out,
	AS_HELP_STRING([--with-dln-a-out], [use dln_a_out if possible]),
	[
	AS_CASE([$withval],
	[yes], [
	    if test "$enable_shared" = yes; then
		AC_MSG_ERROR(dln_a_out can not make shared library)
	    fi
	    with_dln_a_out=yes],
	[
	    with_dln_a_out=no])], [with_dln_a_out=no])

AC_CACHE_CHECK(whether ELF binaries are produced, rb_cv_binary_elf,
[AC_TRY_LINK([],[], [
AS_CASE(["`head -1 conftest$EXEEXT | tr -dc '\177ELF' | tr '\177' .`"],
[.ELF*], [rb_cv_binary_elf=yes], [rb_cv_binary_elf=no])],
rb_cv_binary_elf=no)])

if test "$rb_cv_binary_elf" = yes; then
  AC_DEFINE(USE_ELF)
  if test "$with_dln_a_out" = yes; then
    AC_MSG_ERROR(dln_a_out does not work with ELF)
  fi
  AC_CHECK_HEADERS([elf.h elf_abi.h])
  if test $ac_cv_header_elf_h = yes -o $ac_cv_header_elf_abi_h = yes; then
    AC_LIBOBJ([addr2line])
  fi
fi

AS_CASE(["$target_os"],
[linux* | gnu* | k*bsd*-gnu | bsdi* | kopensolaris*-gnu | nacl], [
    if test "$rb_cv_binary_elf" = no; then
	with_dln_a_out=yes
    else
	LDFLAGS="$LDFLAGS -rdynamic"
    fi])
LIBEXT=a

AC_SUBST(DLDFLAGS)dnl
AC_SUBST(ARCH_FLAG)dnl

AC_SUBST(STATIC)dnl
AC_SUBST(CCDLFLAGS)dnl
AC_SUBST(LDSHARED)dnl
AC_SUBST(LDSHAREDXX)dnl
AC_SUBST(DLEXT)dnl
AC_SUBST(DLEXT2)dnl
AC_SUBST(LIBEXT)dnl
AC_SUBST(ASMEXT, S)dnl

STATIC=

if test "$with_dln_a_out" != yes; then
  rb_cv_dlopen=unknown
  AC_MSG_CHECKING(whether OS depend dynamic link works)
  if test "$GCC" = yes; then
    AS_CASE(["$target_os"],
    [darwin*], [
      # The -fno-common is needed if we wish to embed the Ruby interpreter
      # into a plugin module of some project (as opposed to embedding it
      # within the project's application).  The -I/usr/local/include is
      # needed because CPP as discovered by configure (cc -E -traditional)
      # fails to consult /usr/local/include by default.  This causes
      # mkmf.rb's have_header() to fail if the desired resource happens to be
      # installed in the /usr/local tree.
      RUBY_APPEND_OPTION(CCDLFLAGS, -fno-common)],
    [bsdi*|cygwin*|mingw*|aix*|interix*], [ ],
    [
      RUBY_APPEND_OPTION(CCDLFLAGS, -fPIC)])
  else
    AS_CASE(["$target_os"],
	[hpux*],          [CCDLFLAGS="$CCDLFLAGS +Z"],
	[solaris*|irix*], [CCDLFLAGS="$CCDLFLAGS -KPIC"],
	[sunos*],         [CCDLFLAGS="$CCDLFLAGS -PIC"],
	[esix*|uxpds*],   [CCDLFLAGS="$CCDLFLAGS -KPIC"],
	                  [: ${CCDLFLAGS=""}])
  fi


  AC_ARG_ENABLE(rpath,
       AS_HELP_STRING([--enable-rpath], [embed run path into extension libraries.
       enabled by default on ELF platforms]),
       [enable_rpath=$enableval], [enable_rpath="$rb_cv_binary_elf"])

  AS_CASE(["$target_os"],
	[hpux*], [	DLDFLAGS="$DLDFLAGS -E"
			: ${LDSHARED='$(LD) -b'}
			XLDFLAGS="$XLDFLAGS -Wl,-E"
			: ${LIBPATHENV=SHLIB_PATH}
			rb_cv_dlopen=yes],
	[solaris*], [	if test "$GCC" = yes; then
			    : ${LDSHARED='$(CC) -shared'}
			    if test "$rb_cv_prog_gnu_ld" = yes; then
				LDFLAGS="$LDFLAGS -Wl,-E"
			    fi
			else
			    : ${LDSHARED='$(CC) -G'}
			fi
			if test "$ac_cv_sizeof_voidp" = 8; then
			    : ${LIBPATHENV=LD_LIBRARY_PATH_64}
			    : ${PRELOADENV=LD_PRELOAD_64}
			else
			    : ${LIBPATHENV=LD_LIBRARY_PATH_32}
			    : ${PRELOADENV=LD_PRELOAD_32}
			fi
			rb_cv_dlopen=yes],
	[sunos*], [	: ${LDSHARED='$(LD) -assert nodefinitions'}
			rb_cv_dlopen=yes],
	[irix*], [	: ${LDSHARED='$(LD) -shared'}
			rb_cv_dlopen=yes],
	[sysv4*], [	: ${LDSHARED='$(LD) -G'}
			rb_cv_dlopen=yes],
	[nto-qnx*], [	: ${LDSHARED='$(CC) -shared'}
			rb_cv_dlopen=yes],
	[esix*|uxpds*], [ : ${LDSHARED='$(LD) -G'}
			rb_cv_dlopen=yes],
	[osf*], [	: ${LDSHARED='$(LD) -shared -expect_unresolved "*"'}
			rb_cv_dlopen=yes],
	[bsdi3*], [	AS_CASE(["$CC"],
			[*shlicc*], [	: ${LDSHARED='$(CC) -r'}
					rb_cv_dlopen=yes])],
	[linux* | gnu* | k*bsd*-gnu | netbsd* | bsdi* | kopensolaris*-gnu | haiku*], [
			: ${LDSHARED='$(CC) -shared'}
			if test "$rb_cv_binary_elf" = yes; then
			    LDFLAGS="$LDFLAGS -Wl,-export-dynamic"
			fi
			rb_cv_dlopen=yes],
	[interix*], [	: ${LDSHARED='$(CC) -shared'}
			XLDFLAGS="$XLDFLAGS -Wl,-E"
			LIBPATHFLAG=" -L%1\$-s"
			rb_cv_dlopen=yes],
	[freebsd*|dragonfly*], [
			: ${LDSHARED='$(CC) -shared'}
			if test "$rb_cv_binary_elf" = yes; then
			    LDFLAGS="$LDFLAGS -rdynamic"
			    DLDFLAGS="$DLDFLAGS "'-Wl,-soname,$@'
			else
			  test "$GCC" = yes && test "$rb_cv_prog_gnu_ld" = yes || LDSHARED='$(LD) -Bshareable'
			fi
			rb_cv_dlopen=yes],
	[openbsd*|mirbsd*], [	: ${LDSHARED='$(CC) -shared ${CCDLFLAGS}'}
			if test "$rb_cv_binary_elf" = yes; then
			    LDFLAGS="$LDFLAGS -Wl,-E"
			fi
			rb_cv_dlopen=yes],
	[darwin*], [	: ${LDSHARED='$(CC) -dynamic -bundle'}
			: ${LDFLAGS=""}
			: ${LIBPATHENV=DYLD_LIBRARY_PATH}
			: ${PRELOADENV=DYLD_INSERT_LIBRARIES}
			rb_cv_dlopen=yes],
        [aix*], [	: ${LDSHARED='$(CC)'}
			LDSHARED="$LDSHARED ${linker_flag}-G"
			EXTDLDFLAGS='-e$(TARGET_ENTRY)'
			XLDFLAGS="${linker_flag}"'-bE:$(ARCHFILE)'" ${linker_flag}-brtl"
			XLDFLAGS="$XLDFLAGS ${linker_flag}-blibpath:${prefix}/lib:${LIBPATH:-/usr/lib:/lib}"
			: ${ARCHFILE="ruby.imp"}
                        TRY_LINK='$(CC) $(LDFLAGS) -oconftest $(INCFLAGS) -I$(hdrdir) $(CPPFLAGS)'
                        TRY_LINK="$TRY_LINK"' $(CFLAGS) $(src) $(LIBPATH) $(LOCAL_LIBS) $(LIBS)'
			: ${LIBPATHENV=LIBPATH}
			rb_cv_dlopen=yes],
	[nto-qnx*], [	DLDFLAGS="$DLDFLAGS -L/lib -L/usr/lib -L/usr/local/lib"
			: ${LDSHARED='$(LD) -Bshareable -x'}
			LDFLAGS="$LDFLAGS -L/lib -L/usr/lib -L/usr/local/lib"
			rb_cv_dlopen=yes],
	[cygwin*|mingw*], [
			: ${LDSHARED='$(CC) -shared $(if $(filter-out -g -g0,$(debugflags)),,-s)'}
			XLDFLAGS="$XLDFLAGS -Wl,--stack,0x00200000,--enable-auto-import"
			DLDFLAGS="${DLDFLAGS} -Wl,--enable-auto-image-base,--enable-auto-import"
			: ${LIBPATHENV=""}
			: ${PRELOADENV=""}
			rb_cv_dlopen=yes],
	[hiuxmpp], [	: ${LDSHARED='$(LD) -r'}],
	[atheos*], [	: ${LDSHARED='$(CC) -shared'}
			rb_cv_dlopen=yes],
        [nacl], [ LDSHARED='$(CC) -shared' ],
	[	: ${LDSHARED='$(LD)'}])
  AC_MSG_RESULT($rb_cv_dlopen)

  if test "$rb_cv_dlopen" = yes; then
    AS_CASE(["$target_os"],
      [darwin*], [
	for flag in \
	  "-undefined dynamic_lookup" \
	  "-multiply_defined suppress" \
	  ; do
	  test "x${linker_flag}" = x || flag="${linker_flag}`echo ${flag} | tr ' ' ,`"
	  RUBY_TRY_LDFLAGS([$flag], [], [flag=])
	  if test "x$flag" != x; then
	    RUBY_APPEND_OPTIONS(DLDFLAGS, [$flag])
	  fi
	done
      ])
  fi

  AS_IF([test "$enable_rpath:${RPATHFLAG}" = yes:], [
      AS_IF([test "x$rpathflag" != x], [
	  RPATHFLAG=" ${rpathflag}%1\$-s"
      ])
  ])
fi
if test "${LDSHAREDXX}" = ""; then
    AS_CASE(["${LDSHARED}"],
	[*'$(CC)'*], [
	    LDSHAREDXX=`echo "${LDSHARED}" | sed 's/\$(CC)/$(CXX)/'`
	    ],
	[*'${CC}'*], [
	    LDSHAREDXX=`echo "${LDSHARED}" | sed 's/\${CC}/${CXX}/'`
	    ],
	[*$CC*], [
	    LDSHAREDXX=`echo "${LDSHARED}" | sed "s|$CC|$CXX|"`
	    ],
	[ld" "*], [
	    ])
fi
AS_CASE([${RPATHFLAG}],[*'%1$'*],[: ${LIBPATHFLAG=' -L%1$-s'}],[: ${LIBPATHFLAG=' -L%s'}])

AC_SUBST(LINK_SO)
AC_SUBST(LIBPATHFLAG)
AC_SUBST(RPATHFLAG)
AC_SUBST(LIBPATHENV, "${LIBPATHENV-LD_LIBRARY_PATH}")
AC_SUBST(PRELOADENV, "${PRELOADENV-LD_PRELOAD}")
AC_SUBST(TRY_LINK)

if test "x$OPT_DIR" != x; then
    pat=`echo "${LDFLAGS_OPTDIR}" | sed ['s/[][\\.*|]/\\\\&/']`
    LDFLAGS=`echo "${LDFLAGS}" | sed "s| ${pat}||"`
    val=`IFS="$PATH_SEPARATOR"
        for dir in $OPT_DIR; do
            echo x ${LIBPATHFLAG} ${RPATHFLAG} |
            sed "s/^x *//;s${IFS}"'%1\\$-s'"${IFS}${dir}/lib${IFS}g;s${IFS}%s${IFS}${dir}/lib${IFS}g"
        done | tr '\012' ' ' | sed 's/ *$//'`
    if test x"$val" != x; then
	test x"${LDFLAGS}" = x || LDFLAGS="$LDFLAGS "
	LDFLAGS="$LDFLAGS$val"
	test x"${DLDFLAGS}" = x || DLDFLAGS="$DLDFLAGS "
	DLDFLAGS="$DLDFLAGS$val"
    fi
    LDFLAGS_OPTDIR="$val"
fi

AS_CASE(["$target_os"],
[freebsd*], [
    AC_CHECK_LIB([procstat], [procstat_open_sysctl])
    if test "x$ac_cv_lib_procstat_procstat_open_sysctl" = xyes; then
	AC_CHECK_FUNCS(procstat_getvmmap)
    fi
    ])
AS_CASE(["$target_cpu-$target_os"],
[*-darwin*], [
    AC_CHECK_HEADERS([execinfo.h])
    if test "x$ac_cv_header_execinfo_h" = xyes; then
	AC_CHECK_LIB([execinfo], [backtrace])
	AC_CHECK_HEADERS([libunwind.h])
    fi],
[*-freebsd*|x86_64-netbsd*], [
    AC_CHECK_HEADERS([execinfo.h])
    if test "x$ac_cv_header_execinfo_h" = xyes; then
	AC_CHECK_LIB([execinfo], [backtrace])
	AC_CHECK_LIB([unwind], [unw_backtrace])
    fi])
AC_CHECK_FUNCS(backtrace)

if test "x$ac_cv_func_backtrace" = xyes; then
  AC_CACHE_CHECK(for broken backtrace, rb_cv_broken_backtrace,
    [AC_TRY_RUN([
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <signal.h>
#include <execinfo.h>

#define TRACE_SIZE 256

void sigsegv(int signum, siginfo_t *info, void *ctx){
    void *trace[TRACE_SIZE];
    int n = backtrace(trace, TRACE_SIZE);
    if (n > 0) {
	/*fprintf(stdout, "backtrace:%d\n",n);*/
    } else {
	_exit(EXIT_FAILURE);
    }
    _exit(EXIT_SUCCESS);
}
int
main(void)
{
    volatile int *a = NULL;
    stack_t ss;
    ss.ss_sp = malloc(SIGSTKSZ);
    if (ss.ss_sp == NULL) {
	fprintf(stderr, "cannot allocate memory for sigaltstack\n");
	return EXIT_FAILURE;
    }
    ss.ss_size = SIGSTKSZ;
    ss.ss_flags = 0;
    if (sigaltstack(&ss, NULL) == -1) {
	fprintf(stderr, "sigaltstack failed\n");
	return EXIT_FAILURE;
    }
    struct sigaction sa;
    memset(&sa, 0, sizeof(struct sigaction));
    sigemptyset(&sa.sa_mask);
    sa.sa_sigaction = sigsegv;
    sa.sa_flags |= SA_SIGINFO;
    sa.sa_flags |= SA_ONSTACK;
    sigaction(SIGSEGV, &sa, NULL);
    a[0] = 1;
    return EXIT_SUCCESS;
}
],
	rb_cv_broken_backtrace=no,
	rb_cv_broken_backtrace=yes,
	rb_cv_broken_backtrace=no)])
  if test "$rb_cv_broken_backtrace" = yes; then
    AC_DEFINE(BROKEN_BACKTRACE, 1)
  fi
fi

AC_ARG_WITH(valgrind,
        AS_HELP_STRING([--without-valgrind],[disable valgrind memcheck support]),
        [], with_valgrind=yes)
AS_IF([test x$with_valgrind != xno],
        [AC_CHECK_HEADERS(valgrind/memcheck.h)])

dln_a_out_works=no
if test "$ac_cv_header_a_out_h" = yes; then
  if test "$with_dln_a_out" = yes || test "$rb_cv_dlopen" = unknown; then
    cat confdefs.h > config.h
    AC_CACHE_CHECK(whether matz's dln works, rb_cv_dln_a_out,
    [AC_TRY_COMPILE([
#define USE_DLN_A_OUT
#include "dln.c"
],
	[],
	rb_cv_dln_a_out=yes,
	rb_cv_dln_a_out=no)])
    if test "$rb_cv_dln_a_out" = yes; then
      dln_a_out_works=yes
      AC_DEFINE(USE_DLN_A_OUT)
    fi
  fi
fi

if test "$dln_a_out_works" = yes; then
  if test "$GCC" = yes; then
    STATIC=-static
  else
    STATIC=-Bstatic
  fi
  DLEXT=so
  CCDLFLAGS=
else
  AS_CASE(["$target_os"],
    [hpux*], [
	DLEXT=sl],
    [darwin*], [
	RUBY_APPEND_OPTION(XLDFLAGS, [-Wl,-u,_objc_msgSend])
	DLEXT=bundle],
    [cygwin*|mingw*|*djgpp*], [
	LOAD_RELATIVE=1
	DLEXT=so],
    [
	DLEXT=so])
fi
if test "$rb_cv_dlopen:$load_relative" = yes:yes; then
    if test "$ac_cv_func_dladdr" = yes; then
	LOAD_RELATIVE=1
    fi
fi
if test x"$LOAD_RELATIVE" = x1; then
    load_relative=yes
else
    unset load_relative
fi

len=2 # .rb
n=`expr "$DLEXT"  : '.*'`; test "$n" -gt "$len" && len=$n
n=`expr "$DLEXT2" : '.*'`; test "$n" -gt "$len" && len=$n
AC_DEFINE_UNQUOTED(DLEXT_MAXLEN, `expr $len + 1`)
test ".$DLEXT"  = "." || AC_DEFINE_UNQUOTED(DLEXT,  ".$DLEXT")
test ".$DLEXT2" = "." || AC_DEFINE_UNQUOTED(DLEXT2, ".$DLEXT2")
AC_SUBST(DLEXT)

if test "$with_dln_a_out" = yes; then
  STRIP=true
else
  AC_CHECK_TOOL(STRIP, strip, :)dnl
fi

AS_CASE(["$target_os"],
  [linux* | gnu* | k*bsd*-gnu | kopensolaris*-gnu], [
	STRIP="$STRIP -S -x"],
  [darwin*], [
	STRIP="$STRIP -A -n"])

AC_ARG_WITH(ext,
            AC_HELP_STRING([--with-ext=EXTS],
                           [pass to --with-ext option of extmk.rb]))
AC_ARG_WITH(out-ext,
            AC_HELP_STRING([--with-out-ext=EXTS],
                           [pass to --without-ext option of extmk.rb]))
EXTSTATIC=
AC_SUBST(EXTSTATIC)dnl
AC_ARG_WITH(static-linked-ext,
	    AS_HELP_STRING([--with-static-linked-ext], [link external modules statically]),
            [AS_CASE([$withval],[yes],[STATIC=;EXTSTATIC=static],[no],[],[EXTSTATIC="$withval"])])
AS_CASE([",$EXTSTATIC,"], [,static,|*,enc,*], [
  ENCOBJS='enc/encinit.$(OBJEXT) enc/libenc.$(LIBEXT) enc/libtrans.$(LIBEXT)'
  EXTOBJS='ext/extinit.$(OBJEXT)'
  AC_DEFINE_UNQUOTED(EXTSTATIC, 1)
  AC_SUBST(ENCSTATIC, static)
], [
  ENCOBJS='dmyenc.$(OBJEXT)'
  EXTOBJS='dmyext.$(OBJEXT)'
])
AC_SUBST(ENCOBJS)
AC_SUBST(EXTOBJS)

AC_ARG_WITH(setup,
	    AS_HELP_STRING([--with-setup=SETUP], [use extension libraries setup]),
	    [setup=$withval])
if test -n "$setup"; then
    if ! test -f "ext/$setup" -o -f "$srcdir/ext/$setup"; then
	AC_MSG_ERROR(Setup file $setup not found under ext or $srcdir/ext)
    fi
elif test -f "$srcdir/ext/Setup.$target_os"; then
    setup="Setup.$target_os"
else
    setup=
    for file in "$srcdir"/ext/Setup.*; do
	AS_CASE(["$file"], [*~|*.bak|*.orig|*.rej|*.tmp], [continue])
	setup=`basename "$file"`
	AS_CASE(["$target_os"], [`expr "$setup" : 'Setup.\(.*\)'`*], [break])
	platform=`sed '/^option  *platform  */!d;s///;s/|/*|/g;q' "$file"`
	if test "x$platform" != x; then
	    eval "AS_CASE([\"\$target_os\"], [$platform*], [break])"
	fi
	setup=
    done
    : ${setup:=Setup}
fi
AC_SUBST(setup)

rubylibprefix='${libdir}/${RUBY_BASE_NAME}'
AC_ARG_WITH(rubylibprefix,
	    AS_HELP_STRING([--with-rubylibprefix=DIR], [prefix for ruby libraries [[LIBDIR/RUBY_BASE_NAME]]]),
	    [if test "x$withval" = xno; then
		AC_MSG_ERROR([No ruby, No libprefix])
	    fi
	    rubylibprefix="$withval"])
AC_SUBST(rubylibprefix)

if test x"${exec_prefix}" != xNONE; then
    RUBY_EXEC_PREFIX="$exec_prefix"
elif test x"$prefix" != xNONE; then
    RUBY_EXEC_PREFIX="$prefix"
else
    RUBY_EXEC_PREFIX=$ac_default_prefix
fi
pat=`echo "${RUBY_EXEC_PREFIX}" | tr -c '\012' .`'\(.*\)'
for var in bindir libdir rubylibprefix; do
    eval val='"$'$var'"'
    AS_CASE(["$val"], ["${RUBY_EXEC_PREFIX}"*], [val='${exec_prefix}'"`expr \"$val\" : \"$pat\"`"])
    eval $var='"$val"'
done

BTESTRUBY='$(MINIRUBY)'
if test x"$cross_compiling" = xyes; then
  test x"$MINIRUBY" = x && MINIRUBY="${RUBY-$BASERUBY} -I`$CHDIR .; pwd` "-r'$(arch)-fake'
  XRUBY_LIBDIR=`${RUBY-$BASERUBY} -rrbconfig -e ['puts RbConfig::CONFIG["libdir"]']`
  XRUBY_RUBYLIBDIR=`${RUBY-$BASERUBY} -rrbconfig -e ['puts RbConfig::CONFIG["rubylibdir"]']`
  XRUBY_RUBYHDRDIR=`${RUBY-$BASERUBY} -rrbconfig -e ['puts RbConfig::CONFIG["rubyhdrdir"]']`
  AC_SUBST(XRUBY_LIBDIR)
  AC_SUBST(XRUBY_RUBYLIBDIR)
  AC_SUBST(XRUBY_RUBYHDRDIR)
  PREP='$(arch)-fake.rb'
  RUNRUBY_COMMAND='$(MINIRUBY) -I`cd $(srcdir)/lib; pwd`'
  RUNRUBY='$(RUNRUBY_COMMAND)'
  XRUBY='$(MINIRUBY)'
  BOOTSTRAPRUBY='$(BASERUBY)'
  TEST_RUNNABLE=no
  CROSS_COMPILING=yes

  if test "$host_os" = "nacl"; then
      if test "$build_cpu" = "$host_cpu" || test "${nacl_cv_cpu_nick}" = "x86" -a "$host_cpu" = "i686"; then
          nacl_cv_sel_ldr='`$(MINIRUBY) $(srcdir)/nacl/nacl-config.rb sel_ldr`'
          nacl_cv_irt_core='`$(MINIRUBY) $(srcdir)/nacl/nacl-config.rb irt_core`'
          nacl_cv_runnable_ld='`$(MINIRUBY) $(srcdir)/nacl/nacl-config.rb runnable_ld`'
          nacl_cv_host_lib='`$(MINIRUBY) $(srcdir)/nacl/nacl-config.rb host_lib`'
          TEST_RUNNABLE=yes
          BTESTRUBY="${nacl_cv_sel_ldr} -a -B ${nacl_cv_irt_core} -w 1:3 -w 2:4"
          BTESTRUBY="$BTESTRUBY -- ${nacl_cv_runnable_ld} --library-path ${nacl_cv_host_lib}"
          BTESTRUBY="$BTESTRUBY `pwd`/"'miniruby$(EXEEXT) -I`cd $(srcdir)/lib; pwd` -I.'
          BTESTRUBY="$BTESTRUBY"' -I$(EXTOUT)/common 3>&1 4>&2 1>/dev/null 2>/dev/null '
      fi
  fi
else
  MINIRUBY='./miniruby$(EXEEXT) -I$(srcdir)/lib -I.'
  MINIRUBY="$MINIRUBY"' -I$(EXTOUT)/common'
  PREP='miniruby$(EXEEXT)'
  RUNRUBY_COMMAND='$(MINIRUBY) $(srcdir)/tool/runruby.rb --extout=$(EXTOUT) $(RUNRUBYOPT)'
  RUNRUBY='$(RUNRUBY_COMMAND) --'
  XRUBY='$(RUNRUBY)'
  BOOTSTRAPRUBY='$(MINIRUBY)'
  TEST_RUNNABLE=yes
  CROSS_COMPILING=no
fi
AC_SUBST(TEST_RUNNABLE)
AC_SUBST(CROSS_COMPILING)
AC_SUBST(MINIRUBY)
AC_SUBST(BTESTRUBY)
AC_SUBST(PREP)
AC_SUBST(RUNRUBY_COMMAND)
AC_SUBST(RUNRUBY)
AC_SUBST(XRUBY)
AC_SUBST(BOOTSTRAPRUBY)
AC_SUBST(EXTOUT, [${EXTOUT=.ext}])

FIRSTMAKEFILE=""
LIBRUBY_A='lib$(RUBY_SO_NAME)-static.a'
LIBRUBY='$(LIBRUBY_A)'
LIBRUBYARG_STATIC='-l$(RUBY_SO_NAME)-static'
LIBRUBYARG='$(LIBRUBYARG_STATIC)'
SOLIBS=

AS_CASE(["$target_os"],
  [cygwin*|mingw*|haiku*|darwin*], [
    : ${DLDLIBS=""}
    ],
  [
    DLDLIBS="$DLDLIBS -lc"
    ])

AC_ARG_ENABLE(multiarch,
	      AS_HELP_STRING([--enable-multiarch], [enable multiarch compatible directories]),
	      [multiarch=], [unset multiarch])
if test ${multiarch+set}; then
   AC_DEFINE(ENABLE_MULTIARCH)
fi

archlibdir='${libdir}/${arch}'
sitearchlibdir='${libdir}/${sitearch}'
archincludedir='${includedir}/${arch}'
sitearchincludedir='${includedir}/${sitearch}'

AC_ARG_WITH(soname,
	AS_HELP_STRING([--with-soname=SONAME], [base name of shared library]),
	[RUBY_SO_NAME=$withval], [RUBY_SO_NAME='$(RUBY_BASE_NAME)'])

LIBRUBY_LDSHARED=$LDSHARED
LIBRUBY_DLDFLAGS=$DLDFLAGS
LIBRUBY_SO='lib$(RUBY_SO_NAME).so.$(RUBY_PROGRAM_VERSION)'
LIBRUBY_ALIASES='lib$(RUBY_SO_NAME).so'
ENABLE_SHARED=no

AC_ARG_ENABLE(shared,
       AS_HELP_STRING([--enable-shared], [build a shared library for Ruby]),
       [enable_shared=$enableval])
libprefix=${multiarch+'$(archlibdir)'}${multiarch-'$(libdir)'}
LIBRUBY_RELATIVE=${load_relative-no}
AS_CASE("$enable_shared", [yes], [
  LIBRUBY='$(LIBRUBY_SO)'
  LIBRUBYARG_SHARED='-l$(RUBY_SO_NAME)'
  LIBRUBYARG='$(LIBRUBYARG_SHARED)'
  LIBRUBY_RELATIVE=no
  test -z "$CCDLFLAGS" || CFLAGS="$CFLAGS $CCDLFLAGS"
  ENABLE_SHARED=yes
  if test "$rb_cv_binary_elf" = yes; then
    SOLIBS='$(LIBS)'
  fi

  # libdir can be overridden in config.site file (on OpenSUSE at least).
  libdir_basename=lib
  if test "$bindir" = '${exec_prefix}/bin'; then
    AS_CASE(["$libdir"], ['${exec_prefix}/'*], [libdir_basename=`basename "$libdir"`])
  fi
  AC_DEFINE_UNQUOTED(LIBDIR_BASENAME, ["${libdir_basename}"])
  libdir_basename="${libdir_basename}"${multiarch+'/${arch}'}

  AS_CASE(["$target_os"],
    [freebsd*|dragonfly*], [],
    [
     if test "$GCC" = yes; then
       RUBY_TRY_LDFLAGS([${linker_flag}--no-undefined], [no_undefined=yes], [no_undefined=no])
       if test "no_undefined" = yes; then
	  RUBY_APPEND_OPTION(EXTLDFLAGS, [${linker_flag}--no-undefined])
       fi
     fi
    ])

  AS_CASE(["$target_os"],
    [sunos4*], [
	LIBRUBY_ALIASES='lib$(RUBY_SO_NAME).so.$(MAJOR).$(MINOR) lib$(RUBY_SO_NAME).so'
	],
    [linux* | gnu* | k*bsd*-gnu | atheos* | kopensolaris*-gnu | haiku*], [
	RUBY_APPEND_OPTIONS(LIBRUBY_DLDFLAGS, ['-Wl,-soname,lib$(RUBY_SO_NAME).so.$(MAJOR).$(MINOR)' "$LDFLAGS_OPTDIR"])
	LIBRUBY_ALIASES='lib$(RUBY_SO_NAME).so.$(MAJOR).$(MINOR) lib$(RUBY_SO_NAME).so'
	if test "$load_relative" = yes; then
	    libprefix="'\$\${ORIGIN}/../${libdir_basename}'"
	    LIBRUBY_RPATHFLAGS="-Wl,-rpath,${libprefix}"
	    LIBRUBY_RELATIVE=yes
	fi
	],
    [freebsd*|dragonfly*], [
	SOLIBS='$(LIBS)'
	LIBRUBY_SO='lib$(RUBY_SO_NAME).so.$(MAJOR)$(MINOR)'
	if test "$rb_cv_binary_elf" != "yes" ; then
	    LIBRUBY_SO="$LIBRUBY_SO.\$(TEENY)"
	    LIBRUBY_ALIASES=''
	fi
	],
    [netbsd*], [
	SOLIBS='$(LIBS)'
	LIBRUBY_SO='lib$(RUBY_SO_NAME).so.$(MAJOR)$(MINOR).$(TEENY)'
	RUBY_APPEND_OPTIONS(LIBRUBY_DLDFLAGS, ['-Wl,-soname,lib$(RUBY_SO_NAME).so.$(MAJOR)$(MINOR)' "$LDFLAGS_OPTDIR"])
	if test "$rb_cv_binary_elf" = yes; then # ELF platforms
	   LIBRUBY_ALIASES='lib$(RUBY_SO_NAME).so.$(MAJOR)$(MINOR) lib$(RUBY_SO_NAME).so'
	else	# a.out platforms
	   LIBRUBY_ALIASES=""
	fi
	],
    [openbsd*|mirbsd*], [
	SOLIBS='$(LIBS)'
	LIBRUBY_SO='lib$(RUBY_SO_NAME).so.$(MAJOR).'`expr ${MINOR} \* 10 + ${TEENY}`
	],
    [solaris*], [
	SOLIBS='$(LIBS)'
	LIBRUBY_SO='lib$(RUBY_SO_NAME).so.$(MAJOR)'
	LIBRUBY_ALIASES='lib$(RUBY_SO_NAME).so.$(RUBY_PROGRAM_VERSION) lib$(RUBY_SO_NAME).so'
	if test "$GCC" = yes; then
	    LIBRUBY_DLDFLAGS="$DLDFLAGS "'-Wl,-h,$(@F)'
	else
	    LIBRUBY_DLDFLAGS="$DLDFLAGS "'-h $(@F)'
	fi
	XLDFLAGS="$XLDFLAGS "'-R${libdir}'
	],
    [hpux*], [
	XLDFLAGS="$XLDFLAGS "'-Wl,+s,+b,$(libdir)'
	LIBRUBY_SO='lib$(RUBY_SO_NAME).sl.$(RUBY_PROGRAM_VERSION)'
	LIBRUBY_ALIASES='lib$(RUBY_SO_NAME).sl.$(MAJOR).$(MINOR) lib$(RUBY_SO_NAME).sl'
	],
    [aix*], [
	RUBY_APPEND_OPTIONS(LIBRUBY_DLDFLAGS, ["${linker_flag}-bnoentry" "$XLDFLAGS" "$LDFLAGS_OPTDIR"])
	LIBRUBYARG_SHARED='-L${libdir} -l${RUBY_SO_NAME}'
	SOLIBS='-lm -lc'
	],
    [darwin*], [
	RUBY_SO_NAME="$RUBY_SO_NAME"'.$(RUBY_PROGRAM_VERSION)'
	LIBRUBY_LDSHARED='$(CC) -dynamiclib'
	if test "$load_relative" = yes; then
	    libprefix="@executable_path/../${libdir_basename}"
	    LIBRUBY_RELATIVE=yes
	fi
	LIBRUBY_DLDFLAGS="$LIBRUBY_DLDFLAGS "'-install_name '${libprefix}'/$(LIBRUBY_SO)'
	LIBRUBY_DLDFLAGS="$LIBRUBY_DLDFLAGS "'-compatibility_version $(MAJOR).$(MINOR)'
	LIBRUBY_DLDFLAGS="$LIBRUBY_DLDFLAGS "'-current_version $(RUBY_PROGRAM_VERSION)'
	if test "$visibility_option" = ld; then
	    LIBRUBY_DLDFLAGS="$LIBRUBY_DLDFLAGS "'-Wl,-unexported_symbol,_Init_*'
	    LIBRUBY_DLDFLAGS="$LIBRUBY_DLDFLAGS "'-Wl,-unexported_symbol,_ruby_static_id_*'
	    LIBRUBY_DLDFLAGS="$LIBRUBY_DLDFLAGS "'-Wl,-unexported_symbol,*_threadptr_*'
	fi
	LIBRUBY_DLDFLAGS="$LIBRUBY_DLDFLAGS "' $(XLDFLAGS)'
	LIBRUBY_SO='lib$(RUBY_SO_NAME).dylib'
	LIBRUBY_ALIASES='lib$(RUBY_BASE_NAME).$(MAJOR).$(MINOR).dylib lib$(RUBY_INSTALL_NAME).dylib'
	SOLIBS='$(LIBS)'
	],
    [interix*], [
	LIBRUBYARG_SHARED='-L. -L${libdir} -l$(RUBY_SO_NAME)'
	],
    [mingw*|cygwin*|mswin*], [
	LIBRUBY_RELATIVE=yes
	])
], [
  LIBRUBYARG_SHARED=

  # enable PIE if possible
  AC_ARG_ENABLE(pie,
          AS_HELP_STRING([--disable-pie], [disable PIE feature]),
          [pie=$enableval], [pie=])
  AS_CASE(["$target_os"],
  [nacl], [
    # -pie implies -shared for NaCl.
    pie=no
  ])
  if test "$GCC" = yes -a -z "$EXTSTATIC" -a "x$pie" != xno; then
    RUBY_TRY_CFLAGS(-fPIE, [pie=yes], [pie=no])
    if test "$pie" = yes; then
      # Use -fPIE when testing -pie.  RUBY_TRY_LDFLAGS sets
      # $save_CFLAGS internally, so set other name here.
      save_CFLAGS_before_pie="$CFLAGS"
      CFLAGS="$CFLAGS -fPIE"

      # gcc need -pie but clang need -Wl,-pie.
      for pie in -pie -Wl,-pie; do
	RUBY_TRY_LDFLAGS([$pie], [], [pie=])
	if test "x$pie" != x; then
	  RUBY_APPEND_OPTION(XCFLAGS, -fPIE)
	  RUBY_APPEND_OPTION(XLDFLAGS, $pie)
	  break
	fi
      done
      CFLAGS="$save_CFLAGS_before_pie"
    fi
  fi
])
if test "$enable_rpath" = yes; then
    test -z "$LIBRUBY_RPATHFLAGS" || LIBRUBY_RPATHFLAGS="$LIBRUBY_RPATHFLAGS "
    rpathflag="${RPATHFLAG}"
    AS_CASE(["${cross_compiling}${load_relative}"], [*yes*], [], [rpathflag="$RPATHFLAG$LIBPATHFLAG"])
    rpathflag=`IFS="$PATH_SEPARATOR"
        echo x "$rpathflag" |
        sed "s/^x *//;s${IFS}"'%1\\$-s'"${IFS}${libprefix}${IFS}g;s${IFS}%s${IFS}${libprefix}${IFS}g"
    `
    LIBRUBY_RPATHFLAGS="$LIBRUBY_RPATHFLAGS${rpathflag}"
    LIBRUBYARG_SHARED="$LIBRUBY_RPATHFLAGS $LIBRUBYARG_SHARED"
    LIBRUBYARG_STATIC="$LIBRUBY_RPATHFLAGS $LIBRUBYARG_STATIC"
fi
AC_SUBST(LIBRUBY_RELATIVE)

LDFLAGS="-L. $LDFLAGS"
AC_SUBST(ARCHFILE)

if test "$EXEEXT" = .exe; then
    EXECUTABLE_EXTS='".exe",".com",".cmd",".bat"'
    AC_DEFINE_UNQUOTED(EXECUTABLE_EXTS, $EXECUTABLE_EXTS)
    EXECUTABLE_EXTS=`echo $EXECUTABLE_EXTS | tr -d '"' | tr , ' '`
    AC_SUBST(EXECUTABLE_EXTS)
fi

AS_CASE("$cross_compiling:${LIBPATHENV}", [yes:* | no:], [], [
    AC_MSG_CHECKING(whether wrapper for $LIBPATHENV is needed)
    AS_IF([env ${LIBPATHENV}=/lib /bin/sh -c ': ${'${LIBPATHENV}'?}' 2>/dev/null],
	[AC_MSG_RESULT(no)],
	[PREP="$PREP"' ruby-runner$(EXEEXT)'
	AC_MSG_RESULT(yes)]
    )
])

AC_ARG_ENABLE(dtrace,
        AS_HELP_STRING([--enable-dtrace],
        [enable DTrace for tracing inside ruby. enabled by default on systems having dtrace]),
        [enable_dtrace=$enableval], [enable_dtrace=auto])

LIBRUBY_A_OBJS='$(OBJS)'
DTRACE_REBUILD=
AS_CASE(["${enable_dtrace}"],
[yes|auto], [
    RUBY_DTRACE_AVAILABLE()
], [
    rb_cv_dtrace_available=no
])
AS_IF([test "${enable_dtrace}" = yes], [dnl
    AS_IF([test -z "$DTRACE"], [dnl
	AC_MSG_ERROR([dtrace(1) is missing])
    ], [test "$cross_compiling" = yes], [dnl
	AC_MSG_ERROR([--enable-dtrace, however, cross compiling])
    ], [test "${rb_cv_dtrace_available}" = "no"], [dnl
       AC_MSG_ERROR([--enable-dtrace, however, USDT is not available])
    ])
])
AS_CASE([$rb_cv_dtrace_available],
[yes*], [dnl
    RUBY_DTRACE_POSTPROCESS()
    AS_IF([test "$rb_cv_prog_dtrace_g" != no], [dnl
	DTRACE_OBJ='probes.$(OBJEXT)'
    ])
    AS_IF([test "$rb_cv_prog_dtrace_g" = rebuild], [dnl
	DTRACE_REBUILD=yes
	LIBRUBY_A_OBJS='$(DTRACE_GLOMMED_OBJ)'
    ])
    AS_CASE("${target_os}", [freebsd*], [dnl
        # FreeBSD's dtrace requires libelf
        LIBS="-lelf $LIBS"
    ])
    DTRACE_EXT=d
], [dnl
    enable_dtrace=no
    DTRACE_EXT=dmyh
])
AC_SUBST(DTRACE_EXT)
AC_SUBST(DTRACE_OBJ)
AC_SUBST(DTRACE_REBUILD)
AC_SUBST(DTRACE_OPT)
AC_SUBST(LIBRUBY_A_OBJS)

RUBY_SETJMP_TYPE
}
{ # build section

dnl build rdoc index if requested
RDOCTARGET=""
CAPITARGET=""
AC_ARG_ENABLE(install-doc,
       AS_HELP_STRING([--disable-install-doc], [do not install either rdoc indexes or C API documents during install]),
       [install_doc=$enableval], [install_doc=yes])
AC_ARG_ENABLE(install-rdoc,
      AS_HELP_STRING([--disable-install-rdoc], [do not install rdoc indexes during install]),
      [install_rdoc=$enableval], [install_rdoc=yes])
AC_ARG_ENABLE(install-capi,
      AS_HELP_STRING([--disable-install-capi], [do not install C API documents during install]),
      [install_capi=$enableval], [install_capi=no])

if test "$install_doc" != no; then
    if test "$install_rdoc" != no; then
	RDOCTARGET="rdoc"
    else
	RDOCTARGET="nodoc"
    fi
    if test "$install_capi" != no -a -n "$DOXYGEN"; then
	CAPITARGET="capi"
    else
	CAPITARGET="nodoc"
    fi
else
    RDOCTARGET="nodoc"
    CAPITARGET="nodoc"
fi

AC_SUBST(RDOCTARGET)
AC_SUBST(CAPITARGET)

AS_CASE(["$RDOCTARGET:$CAPITARGET"],[nodoc:nodoc],[INSTALLDOC=nodoc],[INSTALLDOC=all])
AC_SUBST(INSTALLDOC)

AC_ARG_ENABLE(install-static-library,
	AS_HELP_STRING([--disable-install-static-library], [do not install static ruby library]),
	[INSTALL_STATIC_LIBRARY=$enableval],
	AS_IF([test x"$enable_shared" = xyes],
	    [INSTALL_STATIC_LIBRARY=no],
	    [INSTALL_STATIC_LIBRARY=yes]))
AC_SUBST(INSTALL_STATIC_LIBRARY)

if test "$rb_with_pthread" = "yes"; then
    THREAD_MODEL=pthread
fi
AC_CACHE_CHECK([for prefix of external symbols], rb_cv_symbol_prefix, [
    AC_TRY_COMPILE([extern void conftest_external(void) {}], [], [
	rb_cv_symbol_prefix=`$NM conftest.$ac_objext |
			     sed -n ['/.*T[ 	]\([^ 	]*\)conftest_external.*/!d;s//\1/p;q']`
	],
	[rb_cv_symbol_prefix=''])
    test -n "$rb_cv_symbol_prefix" || rb_cv_symbol_prefix=NONE
])
SYMBOL_PREFIX="$rb_cv_symbol_prefix"
test "x$SYMBOL_PREFIX" = xNONE && SYMBOL_PREFIX=''
DLNOBJ=dln.o
AC_ARG_ENABLE(dln,
	      AC_HELP_STRING([--disable-dln], [disable dynamic link feature]),
	      [test "$enableval" = yes || DLNOBJ=dmydln.o])
AC_SUBST(DLNOBJ)
MINIDLNOBJ=dmydln.o

AS_CASE(["$target_os"],
    [linux*], [
	],
    [netbsd*], [
	RUBY_APPEND_OPTION(CFLAGS, -pipe)
	],
    [darwin*], [
	RUBY_APPEND_OPTION(CFLAGS, -pipe)
	RUBY_APPEND_OPTION(XLDFLAGS, [-framework Foundation])
	RUBY_APPEND_OPTION(LIBRUBYARG_STATIC, [-framework Foundation])
	],
    [osf*], [
	if test "$GCC" != "yes" ; then
	  # compile something small: taint.c is fine for this.
	  # the main point is the '-v' flag of 'cc'.
	  AS_CASE(["`cc -v -I. -c main.c -o /tmp/main.o 2>&1`"],
	  [*/gemc_cc*], [   # we have the new DEC GEM CC
                        CFLAGS="$CFLAGS -oldc"
                        ],
          [            # we have the old MIPS CC
                        ])
	  # cleanup
	  rm -f /tmp/main.o
	  CFLAGS="$CFLAGS -std"
	fi
	],
    [cygwin*|mingw*], [
	RUBY_SO_NAME="${RUBY_SO_NAME}"'$(MAJOR)$(MINOR)0'
	LIBRUBY_DLDFLAGS="${DLDFLAGS}"' -Wl,--out-implib=$(LIBRUBY)'
	AS_CASE(["$target_os"],
	[cygwin*], [
	    if test x"$enable_shared" = xyes; then
		LIBRUBY_SO='cyg$(RUBY_SO_NAME)'.dll
		LIBRUBY_DLDFLAGS="${LIBRUBY_DLDFLAGS}"' $(RUBYDEF)'
	    fi
	    ],
	[mingw*], [
	    RUBY_SO_NAME="${rb_cv_msvcrt}-${RUBY_SO_NAME}"
	    if test x"${target_cpu}" != xi386; then
		RUBY_SO_NAME="${target_cpu}-${RUBY_SO_NAME}"
	    fi
	    if test x"$enable_shared" = xyes; then
		LIBRUBY_SO='$(RUBY_SO_NAME)'.dll
		LIBRUBY_DLDFLAGS="${LIBRUBY_DLDFLAGS}"' $(RUBYDEF)'
	    fi
	    EXPORT_PREFIX=' '
	    DLDFLAGS="${DLDFLAGS}"' $(DEFFILE)'
	    AC_LIBOBJ([win32/win32])
	    AC_LIBOBJ([win32/file])
	    COMMON_LIBS=m
#	    COMMON_MACROS="WIN32_LEAN_AND_MEAN="
	    COMMON_HEADERS="winsock2.h windows.h"
	    THREAD_MODEL=win32
	    PLATFORM_DIR=win32
	    ])
	LIBRUBY_ALIASES=''
	FIRSTMAKEFILE=GNUmakefile:cygwin/GNUmakefile.in
	SOLIBS='$(LIBS)'
	if test x"$enable_shared" = xyes; then
	    LIBRUBY='lib$(RUBY_SO_NAME).dll.a'
	else
	    LIBRUBY_SO=dummy
	    LIBRUBY='lib$(RUBY_SO_NAME).a'
	    LIBRUBYARG='-l$(RUBY_SO_NAME)'
	fi
	],
    [hpux*], [
	AS_CASE(["$YACC"],[*yacc*], [
	    XCFLAGS="$XCFLAGS -DYYMAXDEPTH=300"
	    YACC="$YACC -Nl40000 -Nm40000"
	])],
    [nacl], [
	FIRSTMAKEFILE=GNUmakefile:nacl/GNUmakefile.in
	])

MINIOBJS="$MINIDLNOBJ"

AS_CASE(["$THREAD_MODEL"],
[pthread], [AC_CHECK_HEADERS(pthread.h)],
[win32],   [],
[""],      [AC_MSG_ERROR(thread model is missing)],
           [AC_MSG_ERROR(unknown thread model $THREAD_MODEL)])

AC_ARG_ENABLE(debug-env,
       AS_HELP_STRING([--enable-debug-env], [enable RUBY_DEBUG environment variable]),
       [AC_DEFINE(RUBY_DEBUG_ENV)])

AS_CASE(["$FIRSTMAKEFILE"], [*GNUmakefile:*], [gnumake=yes], [
    AC_MSG_CHECKING([if ${MAKE-make} is GNU make])
    mkdir conftest.dir
    echo "all:; @echo yes" > conftest.dir/GNUmakefile
    echo "all:; @echo no" > conftest.dir/Makefile
    gnumake=`(cd conftest.dir; ${MAKE-make})`
    rm -fr conftest.dir
    AS_CASE(["$gnumake"],
    [*yes*], [
	FIRSTMAKEFILE=GNUmakefile:template/GNUmakefile.in
	gnumake=yes],
    [
	gnumake=no])
    AC_MSG_RESULT($gnumake)
])
AS_IF([test "$gnumake" = yes], [ NULLCMD=: ], [
    AC_MSG_CHECKING([for safe null command for ${MAKE-make}])
    mkdir conftest.dir
    NULLCMD=
    for cmd in : true; do
	echo 'A=1' > conftest.dir/Makefile
	echo 'B=$(A:1=@'$cmd')' >> conftest.dir/Makefile
	echo 'all:; $B 1 2 3 4 5 6 7 8 9' >> conftest.dir/Makefile
	if (cd conftest.dir; ${MAKE-make} >/dev/null 2>/dev/null); then
	    NULLCMD=$cmd
	    break
	fi
    done
    rm -fr conftest.dir
    if test -z "$NULLCMD"; then
	AC_MSG_ERROR(no candidate for safe null command)
    fi
    AC_MSG_RESULT($NULLCMD)
])
AC_SUBST(NULLCMD)

if test "${universal_binary-no}" = yes ; then
    AC_CACHE_CHECK([for architecture macros], rb_cv_architecture_macros, [
    mv confdefs.h confdefs1.h
    : > confdefs.h
    AC_TRY_COMPILE([@%:@if defined __`echo ${universal_archnames} |
    sed 's/=[^ ]*//g;s/ /__ || defined __/g'`__
@%:@else
@%:@error
>>>>>><<<<<<
@%:@endif], [],
[
    rb_cv_architecture_macros=yes
    mv -f confdefs1.h confdefs.h
], [
    rb_cv_architecture_macros=no
    archflagpat=`eval echo '"'"${ARCH_FLAG}"'"' | sed 's/[[][|.*]]/\\&/g'`
    new_cflags=`echo "$CFLAGS" | sed "s|$archflagpat"'||'`
    for archs in ${universal_archnames}; do
	cpu=${archs@%:@*=}
	archs=${archs%=*}
	CFLAGS="$new_cflags -arch $archs"
	archs="__${archs}__"
	AC_MSG_CHECKING([for macro ${archs} on ${cpu}])
	AC_TRY_COMPILE([@%:@ifndef ${archs}
@%:@error
@%:@endif], [], [AC_MSG_RESULT([yes])], [AC_MSG_RESULT([no])])
    done
    mv -f confdefs1.h confdefs.h
    AC_MSG_ERROR([failed])
    ])])
    AC_CACHE_CHECK(whether __ARCHITECTURE__ is available, rb_cv_architecture_available,
	AC_TRY_COMPILE([@%:@include <stdio.h>
		const char arch[[]] = __ARCHITECTURE__;], [puts(arch);],
		[rb_cv_architecture_available=yes], [rb_cv_architecture_available=no]))
fi

CPPFLAGS="$CPPFLAGS "'$(DEFS)'
test -z "$CPPFLAGS" || CPPFLAGS="$CPPFLAGS "; CPPFLAGS="$CPPFLAGS"'${cppflags}'
if test -n "${cflags+set}"; then
    cflagspat=`eval echo '"'"${cflags}"'"' | sed 's/[[][|.*]]/\\&/g;s/^  */ /;s/^  *$/ /'`
    CFLAGS=`echo " $CFLAGS " | sed "s|$cflagspat"'|${cflags}|;s/^ *//;s/ *$//'`
fi
if test -n "${cxxflags+set}"; then
    cxxflagspat=`eval echo '"'"${cxxflags}"'"' | sed 's/[[][|.*]]/\\&/g;s/^  */ /;s/^  *$/ /'`
    CXXFLAGS=`echo " $CXXFLAGS " | sed "s|$cxxflagspat"'|${cxxflags}|;s/^ *//;s/ *$//'`
fi
if test "${ARCH_FLAG}"; then
    archflagpat=`eval echo '"'"${ARCH_FLAG}"'"' | sed 's/[[][|.*]]/\\&/g'`
    CFLAGS=`echo "$CFLAGS" | sed "s| *$archflagpat"'||'`
    CXXFLAGS=`echo "$CXXFLAGS" | sed "s| *$archflagpat"'||'`
    LDFLAGS=`echo "$LDFLAGS" | sed "s| *$archflagpat"'||'`
fi
warnflags="$rb_cv_warnflags"
AC_SUBST(cppflags)dnl
AC_SUBST(cflags, ["${orig_cflags:+$orig_cflags }"'${optflags} ${debugflags} ${warnflags}'])dnl
AC_SUBST(cxxflags, ["${orig_cxxflags:+$orig_cxxflags }"'${optflags} ${debugflags} ${warnflags}'])dnl
AC_SUBST(optflags)dnl
AC_SUBST(debugflags)dnl
AC_SUBST(warnflags)dnl
AC_SUBST(strict_warnflags)dnl
AC_SUBST(XCFLAGS)dnl
AC_SUBST(XLDFLAGS)dnl
AC_SUBST(EXTLDFLAGS)dnl
AC_SUBST(EXTDLDFLAGS)dnl
AC_SUBST(LIBRUBY_LDSHARED)
AC_SUBST(LIBRUBY_DLDFLAGS)
AC_SUBST(RUBY_INSTALL_NAME)
AC_SUBST(rubyw_install_name)
AC_SUBST(RUBYW_INSTALL_NAME)
AC_SUBST(RUBY_SO_NAME)
AC_SUBST(LIBRUBY_A)
AC_SUBST(LIBRUBY_SO)
AC_SUBST(LIBRUBY_ALIASES)
AC_SUBST(LIBRUBY)
AC_SUBST(LIBRUBYARG)
AC_SUBST(LIBRUBYARG_STATIC)
AC_SUBST(LIBRUBYARG_SHARED)
AC_SUBST(SOLIBS)
AC_SUBST(DLDLIBS)
AC_SUBST(ENABLE_SHARED)
AC_SUBST(MAINLIBS)
AC_SUBST(COMMON_LIBS)
AC_SUBST(COMMON_MACROS)
AC_SUBST(COMMON_HEADERS)
AC_SUBST(EXPORT_PREFIX)
AC_SUBST(SYMBOL_PREFIX)
AC_SUBST(MINIOBJS)
AC_SUBST(THREAD_MODEL)
AC_SUBST(PLATFORM_DIR)

firstmf=`echo $FIRSTMAKEFILE | sed 's/:.*//'`
firsttmpl=`echo $FIRSTMAKEFILE | sed 's/.*://'`
MAKEFILES="Makefile $firstmf"
MAKEFILES="`echo $MAKEFILES`"
AC_SUBST(MAKEFILES)

ri_prefix=
test "$program_prefix" != NONE &&
  ri_prefix=$program_prefix

ri_suffix=
test "$program_suffix" != NONE &&
  ri_suffix=$program_suffix

RUBY_INSTALL_NAME="${ri_prefix}"'$(RUBY_BASE_NAME)'"${ri_suffix}"
AS_CASE(["$target_os"],
  [cygwin*|mingw*], [
    RUBYW_INSTALL_NAME="${ri_prefix}"'$(RUBYW_BASE_NAME)'"${ri_suffix}"
    rubyw_install_name='$(RUBYW_INSTALL_NAME)'
    ])

rubylibdir='${rubylibprefix}/${ruby_version}'
rubyarchdir=${multiarch+'${rubyarchprefix}/${ruby_version}'}${multiarch-'${rubylibdir}/${arch}'}

rubyarchprefix=${multiarch+'${archlibdir}/${RUBY_BASE_NAME}'}${multiarch-'${rubylibprefix}/${arch}'}
AC_ARG_WITH(rubyarchprefix,
	    AS_HELP_STRING([--with-rubyarchprefix=DIR],
			   [prefix for architecture dependent ruby libraries [[RUBYLIBPREFIX/ARCH]]]),
	    [rubyarchprefix="$withval"])
AC_SUBST(rubyarchprefix)

rubysitearchprefix=${multiarch+'${sitearchlibdir}/${RUBY_BASE_NAME}'}${multiarch-'${rubylibprefix}/${sitearch}'}
AC_ARG_WITH(rubysitearchprefix,
	    AS_HELP_STRING([--with-rubysitearchprefix=DIR],
			   [prefix for architecture dependent site libraries [[RUBYLIBPREFIX/SITEARCH]]]),
	    [rubysitearchprefix="$withval"])
AC_SUBST(rubysitearchprefix)

RI_BASE_NAME=`echo ${RUBY_BASE_NAME} | sed 's/ruby/ri/'`
ridir='${datarootdir}/${RI_BASE_NAME}'
AC_ARG_WITH(ridir,
	    AS_HELP_STRING([--with-ridir=DIR], [ri documentation [[DATAROOTDIR/ri]]]),
	    [ridir=$withval])
AC_SUBST(ridir)
AC_SUBST(RI_BASE_NAME)

AC_ARG_WITH(ruby-version,
	    AS_HELP_STRING([--with-ruby-version=STR], [ruby version string for version specific directories [[full]] (full|minor|STR)]),
            [ruby_version=$withval],
            [ruby_version=full])
unset RUBY_LIB_VERSION
unset RUBY_LIB_VERSION_STYLE
AS_CASE(["$ruby_version"],
  [full],  [RUBY_LIB_VERSION_STYLE='3	/* full */'],
  [minor], [RUBY_LIB_VERSION_STYLE='2	/* minor */'])
if test ${RUBY_LIB_VERSION_STYLE+set}; then
    {
    echo "#define RUBY_LIB_VERSION_STYLE $RUBY_LIB_VERSION_STYLE"
    echo '#define STRINGIZE(x) x'
    test -f revision.h -o -f "${srcdir}/revision.h" || echo '#define RUBY_REVISION 0'
    echo '#include "version.h"'
    echo 'ruby_version=RUBY_LIB_VERSION'
    } > conftest.c
    ruby_version="`$CPP -I. -I"${srcdir}" -I"${srcdir}/include" conftest.c | sed '/^ruby_version=/!d;s/ //g'`"
    eval $ruby_version
elif test -z "${ruby_version}"; then
    AC_MSG_ERROR([No ruby version, No place for bundled libraries])
else
    RUBY_LIB_VERSION="${ruby_version}"
fi
AC_SUBST(RUBY_LIB_VERSION_STYLE)
AC_SUBST(RUBY_LIB_VERSION)

AC_ARG_WITH(sitedir,
	    AS_HELP_STRING([--with-sitedir=DIR], [site libraries in DIR [[RUBY_LIB_PREFIX/site_ruby]], "no" to disable site directory]),
            [sitedir=$withval],
            [sitedir='${rubylibprefix}/site_ruby'])
sitelibdir='${sitedir}/${ruby_version}'

AC_ARG_WITH(sitearchdir,
	    AS_HELP_STRING([--with-sitearchdir=DIR],
			   [architecture dependent site libraries in DIR [[SITEDIR/SITEARCH]], "no" to disable site directory]),
            [sitearchdir=$withval],
            [sitearchdir=${multiarch+'${rubysitearchprefix}/site_ruby/${ruby_version}'}${multiarch-'${sitelibdir}/${sitearch}'}])

AC_ARG_WITH(vendordir,
	    AS_HELP_STRING([--with-vendordir=DIR], [vendor libraries in DIR [[RUBY_LIB_PREFIX/vendor_ruby]], "no" to disable vendor directory]),
            [vendordir=$withval],
            [vendordir='${rubylibprefix}/vendor_ruby'])
vendorlibdir='${vendordir}/${ruby_version}'

AC_ARG_WITH(vendorarchdir,
	    AS_HELP_STRING([--with-vendorarchdir=DIR],
			   [architecture dependent vendor libraries in DIR [[VENDORDIR/SITEARCH]], "no" to disable vendor directory]),
            [vendorarchdir=$withval],
            [vendorarchdir=${multiarch+'${rubysitearchprefix}/vendor_ruby/${ruby_version}'}${multiarch-'${vendorlibdir}/${sitearch}'}])

if test "${LOAD_RELATIVE+set}"; then
    AC_DEFINE_UNQUOTED(LOAD_RELATIVE, $LOAD_RELATIVE)
    RUBY_EXEC_PREFIX=''
fi

AC_SUBST(RUBY_EXEC_PREFIX)

AC_SUBST(libdirname, ${multiarch+arch}libdir)
AC_SUBST(archlibdir)dnl
AC_SUBST(sitearchlibdir)dnl
AC_SUBST(archincludedir)dnl
AC_SUBST(sitearchincludedir)dnl
AC_SUBST(arch)dnl
AC_SUBST(sitearch)dnl
AC_SUBST(ruby_version)dnl
AC_SUBST(rubylibdir)dnl
AC_SUBST(rubyarchdir)dnl
AC_SUBST(sitedir)dnl
AC_SUBST(sitelibdir)dnl
AC_SUBST(sitearchdir)dnl
AC_SUBST(vendordir)dnl
AC_SUBST(vendorlibdir)dnl
AC_SUBST(vendorarchdir)dnl

AC_SUBST(CONFIGURE, "`echo $0 | sed 's|.*/||'`")dnl
AC_SUBST(configure_args, "`echo "${ac_configure_args}" | sed 's/\\$/$$/g'`")dnl

if test "${universal_binary-no}" = yes ; then
    arch="universal-${target_os}"
    if test "${rb_cv_architecture_available}" = yes; then
	AC_DEFINE_UNQUOTED(RUBY_PLATFORM_CPU, __ARCHITECTURE__)
    else
	for archs in ${universal_archnames}; do
	    cpu=`echo $archs | sed 's/.*=//'`
	    archs=`echo $archs | sed 's/=.*//'`
	    RUBY_DEFINE_IF([defined __${archs}__], RUBY_PLATFORM_CPU, ["${cpu}"])
	done
    fi
    ints='long int short'
    test "$ac_cv_type_long_long" = yes && ints="'long long' $ints"
    AC_SUBST(UNIVERSAL_ARCHNAMES, "${universal_archnames}")
    AC_SUBST(UNIVERSAL_INTS, "${ints}")
    AC_DEFINE_UNQUOTED(RUBY_PLATFORM_OS, "${target_os}")
    AC_DEFINE_UNQUOTED(RUBY_ARCH, "universal-"RUBY_PLATFORM_OS)
    AC_DEFINE_UNQUOTED(RUBY_PLATFORM, "universal."RUBY_PLATFORM_CPU"-"RUBY_PLATFORM_OS)
else
    arch="${target_cpu}-${target_os}"
    AS_CASE(["$arch"], [le32-nacl], [arch="pnacl"])
    AC_DEFINE_UNQUOTED(RUBY_PLATFORM, "$arch")
fi

unset sitearch
AS_CASE(["$target_os"],[mingw*],[sitearch="$target_cpu-$rb_cv_msvcrt"])
: ${sitearch='${arch}'}

AC_ARG_WITH(search-path,
		AS_HELP_STRING([--with-search-path=DIR], [specify the additional search path]),
		[search_path=$withval])
if test "$search_path" != ""; then
    AC_SUBST(RUBY_SEARCH_PATH, $search_path)
fi

AC_ARG_WITH(rubyhdrdir,
	    AS_HELP_STRING([--with-rubyhdrdir=DIR], [core headers in DIR [[INCLUDEDIR/RUBY_BASE_NAME-RUBY_VERSION]]]),
	    [rubyhdrdir=$withval],
	    [rubyhdrdir='${includedir}/${RUBY_VERSION_NAME}'])

AC_ARG_WITH(rubyarchhdrdir,
	    AS_HELP_STRING([--with-rubyarchhdrdir=DIR],
			   [architecture dependent core headers in DIR [[$(rubyhdrdir)/$(arch)]]]),
	    [rubyarchhdrdir=$withval],
	    [rubyarchhdrdir=${multiarch+'${archincludedir}/${RUBY_VERSION_NAME}'}${multiarch-'${rubyhdrdir}/${arch}'}])

AC_ARG_WITH(sitehdrdir,
	    AS_HELP_STRING([--with-sitehdrdir=DIR], [core site headers in DIR [[RUBYHDRDIR/site_ruby]]]),
	    [sitehdrdir=$withval],
	    [sitehdrdir='${rubyhdrdir}/site_ruby'])

AC_ARG_WITH(sitearchhdrdir,
	    AS_HELP_STRING([--with-sitearchhdrdir=DIR],
			   [architecture dependent core site headers in DIR [[RUBYHDRDIR/site_ruby]]]),
	    [sitearchhdrdir=$withval],
	    [sitearchhdrdir=${multiarch+'${sitearchincludedir}/${RUBY_VERSION_NAME}/site_ruby'}${multiarch-'${sitehdrdir}/${sitearch}'}])

AC_ARG_WITH(vendorhdrdir,
	    AS_HELP_STRING([--with-vendorhdrdir=DIR], [core vendor headers in DIR [[RUBYHDRDIR/vendor_ruby]]]),
	    [vendorhdrdir=$withval],
	    [vendorhdrdir='${rubyhdrdir}/vendor_ruby'])

AC_ARG_WITH(vendorarchhdrdir,
	    AS_HELP_STRING([--with-vendorarchhdrdir=DIR],
			   [architecture dependent core vendor headers in DIR [[RUBYHDRDIR/vendor_ruby]]]),
	    [vendorarchhdrdir=$withval],
	    [vendorarchhdrdir=${multiarch+'${sitearchincludedir}/${RUBY_VERSION_NAME}/vendor_ruby'}${multiarch-'${vendorhdrdir}/${sitearch}'}])

AC_SUBST(rubyhdrdir)dnl
AC_SUBST(sitehdrdir)dnl
AC_SUBST(vendorhdrdir)dnl
AC_SUBST(rubyarchhdrdir)dnl
AC_SUBST(sitearchhdrdir)dnl
AC_SUBST(vendorarchhdrdir)dnl

AC_ARG_WITH(mantype,
	AS_HELP_STRING([--with-mantype=TYPE], [specify man page type; TYPE is one of man and doc]),
		[
			AS_CASE(["$withval"],
			[man|man.gz|man.bz2|doc|doc.gz|doc.bz2], [MANTYPE=$withval],
			[AC_MSG_ERROR(invalid man type: $withval)])
		])
if test -z "$MANTYPE"; then
	AC_PATH_PROGS(NROFF, nroff awf, /bin/false, "/usr/bin:/usr/ucb")
	if ${NROFF} -mdoc ${srcdir}/man/ruby.1 >/dev/null 2>&1; then
		MANTYPE=doc
	else
		MANTYPE=man
	fi
fi
AC_SUBST(MANTYPE)

AC_ARG_ENABLE(rubygems,
	AS_HELP_STRING([--disable-rubygems], [disable rubygems by default]),
	[enable_rubygems="$enableval"], [enable_rubygems=yes])
if test x"$enable_rubygems" = xno; then
    AC_DEFINE(DISABLE_RUBYGEMS, 1)
    USE_RUBYGEMS=NO
else
    USE_RUBYGEMS=YES
fi
AC_SUBST(USE_RUBYGEMS)

arch_hdrdir="${EXTOUT}/include/${arch}/ruby"
AS_MKDIR_P("${arch_hdrdir}")
config_h="${arch_hdrdir}/config.h"
guard=INCLUDE_RUBY_CONFIG_H
{
  echo "#ifndef $guard"
  echo "#define $guard 1"
  grep -v "^#define PACKAGE_" confdefs.h
  echo "#endif /* $guard */"
} | tr -d '\015' |
(
  if test "x$CONFIGURE_TTY" = xyes; then color=--color; else color=; fi
  exec ${srcdir}/tool/ifchange $color "${config_h}" -
) || AC_MSG_ERROR([failed to create ${config_h}])
tr -d '\015' < largefile.h > confdefs.h
rm largefile.h

BUILTIN_ENCS=["`sed -n -e '/^BUILTIN_ENCS[ 	]*=/{' \
	-e s/// -e :l -e '/\\\\$/N' -e 's/\\\\\\n/ /' -e 't l' -e p \
	-e '}' "${srcdir}/enc/Makefile.in"`"]
BUILTIN_ENCOBJS=
for e in $BUILTIN_ENCS; do BUILTIN_ENCOBJS="$BUILTIN_ENCOBJS "`echo $e | sed 's/\.c$/.$(OBJEXT)/'`; done
AC_SUBST(BUILTIN_ENCOBJS)

BUILTIN_TRANSES=["`sed -n -e '/^BUILTIN_TRANSES[ 	]*=/{' \
	-e s/// -e :l -e '/\\\\$/N' -e 's/\\\\\\n/ /' -e 't l' -e p \
	-e '}' "${srcdir}/enc/Makefile.in"`"]
BUILTIN_TRANSSRCS=
BUILTIN_TRANSOBJS=
for e in $BUILTIN_TRANSES; do
  BUILTIN_TRANSSRCS="$BUILTIN_TRANSSRCS "`echo $e | sed 's/\.trans$/.c/'`
  BUILTIN_TRANSOBJS="$BUILTIN_TRANSOBJS "`echo $e | sed 's/\.trans$/.$(OBJEXT)/'`
done
AC_SUBST(BUILTIN_TRANSSRCS)
AC_SUBST(BUILTIN_TRANSOBJS)

PACKAGE=$RUBY_BASE_NAME
AC_SUBST(PACKAGE)
AS_MESSAGE([$PACKAGE library version = $ruby_version])

AS_CASE([" $CPP "], [*" $CC "*], [CPP=`echo " $CPP " | sed "s| $CC |"' $(CC) |;s/^ *//;s/  *$//'`])

if test x"$firstmf" != x; then
    AC_CONFIG_FILES($firstmf:$firsttmpl, [], [firstmf="$firstmf" firsttmpl="$firsttmpl"])
fi
AC_CONFIG_FILES(Makefile, [
    tmpmk=confmk$$.tmp
    {
	if test ${VCS+set}; then
	    :
	elif svn info "$srcdir" > /dev/null 2>&1; then
	    VCS='svn'
	elif git_dir=`git --work-tree="$srcdir" --git-dir="$srcdir/.git" rev-parse --git-dir 2>/dev/null`; then
	    if test -d "$git_dir/svn"; then
		VCS='git svn'
	    else
		VCS='git'
	    fi
	else
	    VCS='echo cannot'
	fi
	AS_CASE("$VCS",
		[svn],       [VCSUP='$(VCS) up $(SVNUPOPTIONS)'],
		["git svn"], [VCSUP='$(VCS) rebase $(GITSVNREBASEOPTIONS)'],
		[git],       [VCSUP='$(VCS) pull $(GITPULLOPTIONS)'],
		[VCSUP='$(VCS)'])
	sed -n \
	    -e '[/^@%:@define \(RUBY_RELEASE_[A-Z]*\) \([0-9][0-9]*\)/]{' \
	    -e   's//\1 = \2/' \
	    -e   '[s/ \([0-9]\)$/ 0\1/]' \
	    -e   p \
	    -e '}' "$srcdir/version.h"
	sed '/^MISSING/s/\$U\././g;/^VCS *=/s#@VCS@#'"$VCS"'#;/^VCSUP *=/s#@VCSUP@#'"$VCSUP"'#' Makefile
	echo; test x"$EXEEXT" = x || echo 'miniruby: miniruby$(EXEEXT)'
	if test "$gnumake" != yes; then
	    echo ['$(MKFILES): $(srcdir)/common.mk']
	    sed ['s/{\$([^(){}]*)[^{}]*}//g'] ${srcdir}/common.mk
	else
	    echo 'distclean-local::; @$(RM) GNUmakefile uncommon.mk'
	fi
    } > $tmpmk && if ! grep '^ruby:' $tmpmk > /dev/null; then
	if test "${gnumake}" = yes; then
	    tmpgmk=confgmk$$.tmp
	    {
		echo "include $tmpmk"
		echo "-include uncommon.mk"
	    } > $tmpgmk
	else
	    tmpgmk=$tmpmk
	fi &&
	test -z "`${MAKE-make} -f $tmpgmk info-program | grep '^PROGRAM=ruby$'`" &&
	echo 'ruby: $(PROGRAM);' >> $tmpmk
	test "$tmpmk" = "$tmpgmk" || rm -f "$tmpgmk"
    fi && mv -f $tmpmk Makefile],
[EXEEXT='$EXEEXT' gnumake='$gnumake'])

AC_ARG_WITH([ruby-pc],
	    AC_HELP_STRING([--with-ruby-pc=FILENAME], [pc file basename]),
	    [ruby_pc="$withval"],
	    [ruby_pc="${RUBY_BASE_NAME}-${MAJOR}.${MINOR}.pc"])
AC_SUBST(ruby_pc)
AC_SUBST(exec, [exec])

AC_ARG_WITH(destdir,
	    AS_HELP_STRING([--with-destdir=DESTDIR], [specify default directory to install]),
	    [DESTDIR="$withval"])
AC_SUBST(DESTDIR)

AC_CONFIG_FILES($ruby_pc:template/ruby.pc.in,
    [
    if sed ['s/\$(\([A-Za-z_][A-Za-z0-9_]*\))/${\1}/g;s/@[A-Za-z_][A-Za-z0-9_]*@//'] $ruby_pc > ruby.tmp.pc &&
	{
	    test -z "$PKG_CONFIG" ||
	    PKG_CONFIG_PATH=. $PKG_CONFIG --print-errors ruby.tmp
	}
    then
	mv -f ruby.tmp.pc $ruby_pc
    else
	exit 1
    fi
    ],
    [ruby_pc='$ruby_pc' PKG_CONFIG='$PKG_CONFIG'])

AC_OUTPUT
}
}

AS_IF([${FOLD+:} false], [], [
AS_IF([test "`echo abcdefg hijklmno | fold -s -w10 | sed 1d`" = hijklmno], [FOLD="fold"], [FOLD=])
])
AS_REQUIRE_SHELL_FN([config_summary],
    [AS_FUNCTION_DESCRIBE([config_summary], [NAME, VAL], [configuration summary])],
    [AS_IF([test -z "$2"], [], [
	AS_ECHO_N(["   * $1:                     "]) | head -c26
	AS_IF([test "$FOLD"], [
	    echo "$2" | fold -s -w50 |
	    sed '1!s/^/                          /;$!s/$/\\/'
	], [echo "$2"])
    ])]
)

echo "---"
echo "Configuration summary for $RUBY_BASE_NAME version $RUBY_PROGRAM_VERSION"
echo ""
config_summary "Installation prefix" "$prefix"
config_summary "exec prefix"         "$exec_prefix"
config_summary "arch"                "$arch"
config_summary "site arch"           "$sitearch"
config_summary "RUBY_BASE_NAME"      "$RUBY_BASE_NAME"
config_summary "enable shared"       "$enable_shared"
config_summary "ruby lib prefix"     "$rubylibprefix"
config_summary "site libraries path" "$rubysitearchprefix"
config_summary "vendor path"         "$vendordir"
config_summary "target OS"           "$target_os"
config_summary "compiler"            "$CC"
config_summary "with pthread"        "$enable_pthread"
config_summary "enable shared libs"  "$ENABLE_SHARED"
config_summary "dynamic library ext" "$DLEXT"
config_summary "CFLAGS"              "$cflags"
config_summary "CPPFLAGS"            "$cppflags"
config_summary "LDFLAGS"             "$LDFLAGS"
config_summary "optflags"            "$optflags"
config_summary "debugflags"          "$debugflags"
config_summary "warnflags"           "$warnflags"
config_summary "strip command"       "$STRIP"
config_summary "install doc"         "$install_doc"
config_summary "man page type"       "$MANTYPE"
config_summary "search path"         "$search_path"
config_summary "static-linked-ext"   ${EXTSTATIC:+"yes"}
echo ""
echo "---"
