make/autoconf/toolchain.m4

#
# Copyright (c) 2011, 2018, Oracle and/or its affiliates. All rights reserved.
# DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
#
# This code is free software; you can redistribute it and/or modify it
# under the terms of the GNU General Public License version 2 only, as
# published by the Free Software Foundation.  Oracle designates this
# particular file as subject to the "Classpath" exception as provided
# by Oracle in the LICENSE file that accompanied this code.
#
# This code is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
# version 2 for more details (a copy is included in the LICENSE file that
# accompanied this code).
#
# You should have received a copy of the GNU General Public License version
# 2 along with this work; if not, write to the Free Software Foundation,
# Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
#
# Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
# or visit www.oracle.com if you need additional information or have any
# questions.
#

########################################################################
# This file is responsible for detecting, verifying and setting up the
# toolchain, i.e. the compiler, linker and related utilities. It will setup
# proper paths to the binaries, but it will not setup any flags.
#
# The binaries used is determined by the toolchain type, which is the family of
# compilers and related tools that are used.
########################################################################


# All valid toolchains, regardless of platform (used by help.m4)
VALID_TOOLCHAINS_all="gcc clang solstudio xlc microsoft"

# These toolchains are valid on different platforms
VALID_TOOLCHAINS_linux="gcc clang"
VALID_TOOLCHAINS_solaris="solstudio"
VALID_TOOLCHAINS_macosx="gcc clang"
VALID_TOOLCHAINS_aix="xlc"
VALID_TOOLCHAINS_windows="microsoft"

# Toolchain descriptions
TOOLCHAIN_DESCRIPTION_clang="clang/LLVM"
TOOLCHAIN_DESCRIPTION_gcc="GNU Compiler Collection"
TOOLCHAIN_DESCRIPTION_microsoft="Microsoft Visual Studio"
TOOLCHAIN_DESCRIPTION_solstudio="Oracle Solaris Studio"
TOOLCHAIN_DESCRIPTION_xlc="IBM XL C/C++"

# Minimum supported versions, empty means unspecified
TOOLCHAIN_MINIMUM_VERSION_clang="3.2"
TOOLCHAIN_MINIMUM_VERSION_gcc="4.8"
TOOLCHAIN_MINIMUM_VERSION_microsoft="16.00.30319.01" # VS2010
TOOLCHAIN_MINIMUM_VERSION_solstudio="5.13"
TOOLCHAIN_MINIMUM_VERSION_xlc=""

# Minimum supported linker versions, empty means unspecified
TOOLCHAIN_MINIMUM_LD_VERSION_gcc="2.18"

# Prepare the system so that TOOLCHAIN_CHECK_COMPILER_VERSION can be called.
# Must have CC_VERSION_NUMBER and CXX_VERSION_NUMBER.
# $1 - optional variable prefix for compiler and version variables (BUILD_)
# $2 - optional variable prefix for comparable variable (OPENJDK_BUILD_)
AC_DEFUN([TOOLCHAIN_PREPARE_FOR_VERSION_COMPARISONS],
[
  if test "x[$]$1CC_VERSION_NUMBER" != "x[$]$1CXX_VERSION_NUMBER"; then
    AC_MSG_WARN([C and C++ compiler have different version numbers, [$]$1CC_VERSION_NUMBER vs [$]$1CXX_VERSION_NUMBER.])
    AC_MSG_WARN([This typically indicates a broken setup, and is not supported])
  fi

  # We only check CC_VERSION_NUMBER since we assume CXX_VERSION_NUMBER is equal.
  if [ [[ "[$]$1CC_VERSION_NUMBER" =~ (.*\.){4} ]] ]; then
    AC_MSG_WARN([C compiler version number has more than four parts (W.X.Y.Z): [$]$1CC_VERSION_NUMBER. Comparisons might be wrong.])
  fi

  if [ [[  "[$]$1CC_VERSION_NUMBER" =~ [0-9]{6} ]] ]; then
    AC_MSG_WARN([C compiler version number has a part larger than 99999: [$]$1CC_VERSION_NUMBER. Comparisons might be wrong.])
  fi

  $2COMPARABLE_ACTUAL_VERSION=`$AWK -F. '{ printf("%05d%05d%05d%05d\n", [$]1, [$]2, [$]3, [$]4) }' <<< "[$]$1CC_VERSION_NUMBER"`
])

# Check if the configured compiler (C and C++) is of a specific version or
# newer. TOOLCHAIN_PREPARE_FOR_VERSION_COMPARISONS must have been called before.
#
# Arguments:
#   VERSION:   The version string to check against the found version
#   IF_AT_LEAST:   block to run if the compiler is at least this version (>=)
#   IF_OLDER_THAN:   block to run if the compiler is older than this version (<)
#   PREFIX:   Optional variable prefix for compiler to compare version for (OPENJDK_BUILD_)
BASIC_DEFUN_NAMED([TOOLCHAIN_CHECK_COMPILER_VERSION],
    [*VERSION PREFIX IF_AT_LEAST IF_OLDER_THAN], [$@],
[
  # Need to assign to a variable since m4 is blocked from modifying parts in [].
  REFERENCE_VERSION=ARG_VERSION

  if [ [[ "$REFERENCE_VERSION" =~ (.*\.){4} ]] ]; then
    AC_MSG_ERROR([Internal error: Cannot compare to ARG_VERSION, only four parts (W.X.Y.Z) is supported])
  fi

  if [ [[ "$REFERENCE_VERSION" =~ [0-9]{6} ]] ]; then
    AC_MSG_ERROR([Internal error: Cannot compare to ARG_VERSION, only parts < 99999 is supported])
  fi

  # Version comparison method inspired by http://stackoverflow.com/a/24067243
  COMPARABLE_REFERENCE_VERSION=`$AWK -F. '{ printf("%05d%05d%05d%05d\n", [$]1, [$]2, [$]3, [$]4) }' <<< "$REFERENCE_VERSION"`

  if test [$]ARG_PREFIX[COMPARABLE_ACTUAL_VERSION] -ge $COMPARABLE_REFERENCE_VERSION ; then
    :
    ARG_IF_AT_LEAST
  else
    :
    ARG_IF_OLDER_THAN
  fi
])

# Prepare the system so that TOOLCHAIN_CHECK_COMPILER_VERSION can be called.
# Must have LD_VERSION_NUMBER.
# $1 - optional variable prefix for compiler and version variables (BUILD_)
# $2 - optional variable prefix for comparable variable (OPENJDK_BUILD_)
AC_DEFUN([TOOLCHAIN_PREPARE_FOR_LD_VERSION_COMPARISONS],
[
  if [ [[ "[$]$1LD_VERSION_NUMBER" =~ (.*\.){4} ]] ]; then
    AC_MSG_WARN([Linker version number has more than four parts (W.X.Y.Z): [$]$1LD_VERSION_NUMBER. Comparisons might be wrong.])
  fi

  if [ [[  "[$]$1LD_VERSION_NUMBER" =~ [0-9]{6} ]] ]; then
    AC_MSG_WARN([Linker version number has a part larger than 99999: [$]$1LD_VERSION_NUMBER. Comparisons might be wrong.])
  fi

  $2COMPARABLE_ACTUAL_LD_VERSION=`$AWK -F. '{ printf("%05d%05d%05d%05d\n", [$]1, [$]2, [$]3, [$]4) }' <<< "[$]$1LD_VERSION_NUMBER"`
])

# Check if the configured linker is of a specific version or
# newer. TOOLCHAIN_PREPARE_FOR_LD_VERSION_COMPARISONS must have been called before.
#
# Arguments:
#   VERSION:   The version string to check against the found version
#   IF_AT_LEAST:   block to run if the compiler is at least this version (>=)
#   IF_OLDER_THAN:   block to run if the compiler is older than this version (<)
#   PREFIX:   Optional variable prefix for compiler to compare version for (OPENJDK_BUILD_)
BASIC_DEFUN_NAMED([TOOLCHAIN_CHECK_LINKER_VERSION],
    [*VERSION PREFIX IF_AT_LEAST IF_OLDER_THAN], [$@],
[
  # Need to assign to a variable since m4 is blocked from modifying parts in [].
  REFERENCE_VERSION=ARG_VERSION

  if [ [[ "$REFERENCE_VERSION" =~ (.*\.){4} ]] ]; then
    AC_MSG_ERROR([Internal error: Cannot compare to ARG_VERSION, only four parts (W.X.Y.Z) is supported])
  fi

  if [ [[ "$REFERENCE_VERSION" =~ [0-9]{6} ]] ]; then
    AC_MSG_ERROR([Internal error: Cannot compare to ARG_VERSION, only parts < 99999 is supported])
  fi

  # Version comparison method inspired by http://stackoverflow.com/a/24067243
  COMPARABLE_REFERENCE_VERSION=`$AWK -F. '{ printf("%05d%05d%05d%05d\n", [$]1, [$]2, [$]3, [$]4) }' <<< "$REFERENCE_VERSION"`

  if test [$]ARG_PREFIX[COMPARABLE_ACTUAL_LD_VERSION] -ge $COMPARABLE_REFERENCE_VERSION ; then
    :
    ARG_IF_AT_LEAST
  else
    :
    ARG_IF_OLDER_THAN
  fi
])

# Setup a number of variables describing how native output files are
# named on this platform/toolchain.
AC_DEFUN([TOOLCHAIN_SETUP_FILENAME_PATTERNS],
[
  # Define filename patterns
  if test "x$OPENJDK_TARGET_OS" = xwindows; then
    LIBRARY_PREFIX=
    SHARED_LIBRARY_SUFFIX='.dll'
    STATIC_LIBRARY_SUFFIX='.lib'
    SHARED_LIBRARY='[$]1.dll'
    STATIC_LIBRARY='[$]1.lib'
    OBJ_SUFFIX='.obj'
    EXE_SUFFIX='.exe'
  else
    LIBRARY_PREFIX=lib
    SHARED_LIBRARY_SUFFIX='.so'
    STATIC_LIBRARY_SUFFIX='.a'
    SHARED_LIBRARY='lib[$]1.so'
    STATIC_LIBRARY='lib[$]1.a'
    OBJ_SUFFIX='.o'
    EXE_SUFFIX=''
    if test "x$OPENJDK_TARGET_OS" = xmacosx; then
      # For full static builds, we're overloading the SHARED_LIBRARY
      # variables in order to limit the amount of changes required.
      # It would be better to remove SHARED and just use LIBRARY and
      # LIBRARY_SUFFIX for libraries that can be built either
      # shared or static and use STATIC_* for libraries that are
      # always built statically.
      if test "x$STATIC_BUILD" = xtrue; then
        SHARED_LIBRARY='lib[$]1.a'
        SHARED_LIBRARY_SUFFIX='.a'
      else
        SHARED_LIBRARY='lib[$]1.dylib'
        SHARED_LIBRARY_SUFFIX='.dylib'
      fi
    fi
  fi

  AC_SUBST(LIBRARY_PREFIX)
  AC_SUBST(SHARED_LIBRARY_SUFFIX)
  AC_SUBST(STATIC_LIBRARY_SUFFIX)
  AC_SUBST(SHARED_LIBRARY)
  AC_SUBST(STATIC_LIBRARY)
  AC_SUBST(OBJ_SUFFIX)
  AC_SUBST(EXE_SUFFIX)
])

# Determine which toolchain type to use, and make sure it is valid for this
# platform. Setup various information about the selected toolchain.
AC_DEFUN_ONCE([TOOLCHAIN_DETERMINE_TOOLCHAIN_TYPE],
[
  AC_ARG_WITH(toolchain-type, [AS_HELP_STRING([--with-toolchain-type],
      [the toolchain type (or family) to use, use '--help' to show possible values @<:@platform dependent@:>@])])

  # Use indirect variable referencing
  toolchain_var_name=VALID_TOOLCHAINS_$OPENJDK_BUILD_OS
  VALID_TOOLCHAINS=${!toolchain_var_name}

  if test "x$OPENJDK_TARGET_OS" = xmacosx; then
    if test -n "$XCODEBUILD"; then
      # On Mac OS X, default toolchain to clang after Xcode 5
      XCODE_VERSION_OUTPUT=`"$XCODEBUILD" -version 2>&1 | $HEAD -n 1`
      $ECHO "$XCODE_VERSION_OUTPUT" | $GREP "Xcode " > /dev/null
      if test $? -ne 0; then
        AC_MSG_ERROR([Failed to determine Xcode version.])
      fi
      XCODE_MAJOR_VERSION=`$ECHO $XCODE_VERSION_OUTPUT | \
          $SED -e 's/^Xcode \(@<:@1-9@:>@@<:@0-9.@:>@*\)/\1/' | \
          $CUT -f 1 -d .`
      AC_MSG_NOTICE([Xcode major version: $XCODE_MAJOR_VERSION])
      if test $XCODE_MAJOR_VERSION -ge 5; then
          DEFAULT_TOOLCHAIN="clang"
      else
          DEFAULT_TOOLCHAIN="gcc"
      fi
    else
      # If Xcode is not installed, but the command line tools are
      # then we can't run xcodebuild. On these systems we should
      # default to clang
      DEFAULT_TOOLCHAIN="clang"
    fi
  else
    # First toolchain type in the list is the default
    DEFAULT_TOOLCHAIN=${VALID_TOOLCHAINS%% *}
  fi

  if test "x$with_toolchain_type" = xlist; then
    # List all toolchains
    AC_MSG_NOTICE([The following toolchains are valid on this platform:])
    for toolchain in $VALID_TOOLCHAINS; do
      toolchain_var_name=TOOLCHAIN_DESCRIPTION_$toolchain
      TOOLCHAIN_DESCRIPTION=${!toolchain_var_name}
      $PRINTF "  %-10s  %s\n" $toolchain "$TOOLCHAIN_DESCRIPTION"
    done

    exit 0
  elif test "x$with_toolchain_type" != x; then
    # User override; check that it is valid
    if test "x${VALID_TOOLCHAINS/$with_toolchain_type/}" = "x${VALID_TOOLCHAINS}"; then
      AC_MSG_NOTICE([Toolchain type $with_toolchain_type is not valid on this platform.])
      AC_MSG_NOTICE([Valid toolchains: $VALID_TOOLCHAINS.])
      AC_MSG_ERROR([Cannot continue.])
    fi
    TOOLCHAIN_TYPE=$with_toolchain_type
  else
    # No flag given, use default
    TOOLCHAIN_TYPE=$DEFAULT_TOOLCHAIN
  fi
  AC_SUBST(TOOLCHAIN_TYPE)

  TOOLCHAIN_CC_BINARY_clang="clang"
  TOOLCHAIN_CC_BINARY_gcc="gcc"
  TOOLCHAIN_CC_BINARY_microsoft="cl"
  TOOLCHAIN_CC_BINARY_solstudio="cc"
  TOOLCHAIN_CC_BINARY_xlc="xlc_r"

  TOOLCHAIN_CXX_BINARY_clang="clang++"
  TOOLCHAIN_CXX_BINARY_gcc="g++"
  TOOLCHAIN_CXX_BINARY_microsoft="cl"
  TOOLCHAIN_CXX_BINARY_solstudio="CC"
  TOOLCHAIN_CXX_BINARY_xlc="xlC_r"

  # Use indirect variable referencing
  toolchain_var_name=TOOLCHAIN_DESCRIPTION_$TOOLCHAIN_TYPE
  TOOLCHAIN_DESCRIPTION=${!toolchain_var_name}
  toolchain_var_name=TOOLCHAIN_MINIMUM_VERSION_$TOOLCHAIN_TYPE
  TOOLCHAIN_MINIMUM_VERSION=${!toolchain_var_name}
  toolchain_var_name=TOOLCHAIN_MINIMUM_LD_VERSION_$TOOLCHAIN_TYPE
  TOOLCHAIN_MINIMUM_LD_VERSION=${!toolchain_var_name}
  toolchain_var_name=TOOLCHAIN_CC_BINARY_$TOOLCHAIN_TYPE
  TOOLCHAIN_CC_BINARY=${!toolchain_var_name}
  toolchain_var_name=TOOLCHAIN_CXX_BINARY_$TOOLCHAIN_TYPE
  TOOLCHAIN_CXX_BINARY=${!toolchain_var_name}

  TOOLCHAIN_SETUP_FILENAME_PATTERNS

  if test "x$TOOLCHAIN_TYPE" = "x$DEFAULT_TOOLCHAIN"; then
    AC_MSG_NOTICE([Using default toolchain $TOOLCHAIN_TYPE ($TOOLCHAIN_DESCRIPTION)])
  else
    AC_MSG_NOTICE([Using user selected toolchain $TOOLCHAIN_TYPE ($TOOLCHAIN_DESCRIPTION). Default toolchain is $DEFAULT_TOOLCHAIN.])
  fi
])

# Before we start detecting the toolchain executables, we might need some
# special setup, e.g. additional paths etc.
AC_DEFUN_ONCE([TOOLCHAIN_PRE_DETECTION],
[
  # FIXME: Is this needed?
  AC_LANG(C++)

  # Store the CFLAGS etc passed to the configure script.
  ORG_CFLAGS="$CFLAGS"
  ORG_CXXFLAGS="$CXXFLAGS"

  # autoconf magic only relies on PATH, so update it if tools dir is specified
  OLD_PATH="$PATH"

  # On Windows, we need to detect the visual studio installation first.
  # This will change the PATH, but we need to keep that new PATH even
  # after toolchain detection is done, since the compiler (on x86) uses
  # it for DLL resolution in runtime.
  if test "x$OPENJDK_BUILD_OS" = "xwindows" \
      && test "x$TOOLCHAIN_TYPE" = "xmicrosoft"; then
    TOOLCHAIN_SETUP_VISUAL_STUDIO_ENV
    # Reset path to VS_PATH. It will include everything that was on PATH at the time we
    # ran TOOLCHAIN_SETUP_VISUAL_STUDIO_ENV.
    PATH="$VS_PATH"
    # The microsoft toolchain also requires INCLUDE and LIB to be set.
    export INCLUDE="$VS_INCLUDE"
    export LIB="$VS_LIB"
  else
    if test "x$XCODE_VERSION_OUTPUT" != x; then
      # For Xcode, we set the Xcode version as TOOLCHAIN_VERSION
      TOOLCHAIN_VERSION=`$ECHO $XCODE_VERSION_OUTPUT | $CUT -f 2 -d ' '`
      TOOLCHAIN_DESCRIPTION="$TOOLCHAIN_DESCRIPTION from Xcode $TOOLCHAIN_VERSION"
    else
      # Currently we do not define this for other toolchains. This might change as the need arise.
      TOOLCHAIN_VERSION=
    fi
  fi
  AC_SUBST(TOOLCHAIN_VERSION)

  # Finally add TOOLCHAIN_PATH at the beginning, to allow --with-tools-dir to
  # override all other locations.
  if test "x$TOOLCHAIN_PATH" != x; then
    PATH=$TOOLCHAIN_PATH:$PATH
  fi
])

# Restore path, etc
AC_DEFUN_ONCE([TOOLCHAIN_POST_DETECTION],
[
  # Restore old path, except for the microsoft toolchain, which requires VS_PATH
  # to remain in place. Otherwise the compiler will not work in some siutations
  # in later configure checks.
  if test "x$TOOLCHAIN_TYPE" != "xmicrosoft"; then
    PATH="$OLD_PATH"
  fi

  # Restore the flags to the user specified values.
  # This is necessary since AC_PROG_CC defaults CFLAGS to "-g -O2"
  CFLAGS="$ORG_CFLAGS"
  CXXFLAGS="$ORG_CXXFLAGS"
])

# Check if a compiler is of the toolchain type we expect, and save the version
# information from it. If the compiler does not match the expected type,
# this function will abort using AC_MSG_ERROR. If it matches, the version will
# be stored in CC_VERSION_NUMBER/CXX_VERSION_NUMBER (as a dotted number), and
# the full version string in CC_VERSION_STRING/CXX_VERSION_STRING.
#
# $1 = compiler to test (CC or CXX)
# $2 = human readable name of compiler (C or C++)
AC_DEFUN([TOOLCHAIN_EXTRACT_COMPILER_VERSION],
[
  COMPILER=[$]$1
  COMPILER_NAME=$2

  if test "x$TOOLCHAIN_TYPE" = xsolstudio; then
    # cc -V output typically looks like
    #     cc: Sun C 5.12 Linux_i386 2011/11/16
    # or
    #     cc: Studio 12.5 Sun C 5.14 SunOS_sparc 2016/05/31
    COMPILER_VERSION_OUTPUT=`$COMPILER -V 2>&1`
    # Check that this is likely to be the Solaris Studio cc.
    $ECHO "$COMPILER_VERSION_OUTPUT" | $GREP "^.* Sun $COMPILER_NAME" > /dev/null
    if test $? -ne 0; then
      ALT_VERSION_OUTPUT=`$COMPILER --version 2>&1`
      AC_MSG_NOTICE([The $COMPILER_NAME compiler (located as $COMPILER) does not seem to be the required $TOOLCHAIN_TYPE compiler.])
      AC_MSG_NOTICE([The result from running with -V was: "$COMPILER_VERSION_OUTPUT"])
      AC_MSG_NOTICE([The result from running with --version was: "$ALT_VERSION_OUTPUT"])
      AC_MSG_ERROR([A $TOOLCHAIN_TYPE compiler is required. Try setting --with-tools-dir.])
    fi
    # Remove usage instructions (if present), and
    # collapse compiler output into a single line
    COMPILER_VERSION_STRING=`$ECHO $COMPILER_VERSION_OUTPUT | \
        $SED -e 's/ *@<:@Uu@:>@sage:.*//'`
    COMPILER_VERSION_NUMBER=`$ECHO $COMPILER_VERSION_OUTPUT | \
        $SED -e "s/^.*@<:@ ,\t@:>@$COMPILER_NAME@<:@ ,\t@:>@\(@<:@1-9@:>@\.@<:@0-9@:>@@<:@0-9@:>@*\).*/\1/"`
  elif test  "x$TOOLCHAIN_TYPE" = xxlc; then
    # xlc -qversion output typically looks like
    #     IBM XL C/C++ for AIX, V11.1 (5724-X13)
    #     Version: 11.01.0000.0015
    COMPILER_VERSION_OUTPUT=`$COMPILER -qversion 2>&1`
    # Check that this is likely to be the IBM XL C compiler.
    $ECHO "$COMPILER_VERSION_OUTPUT" | $GREP "IBM XL C" > /dev/null
    if test $? -ne 0; then
      ALT_VERSION_OUTPUT=`$COMPILER --version 2>&1`
      AC_MSG_NOTICE([The $COMPILER_NAME compiler (located as $COMPILER) does not seem to be the required $TOOLCHAIN_TYPE compiler.])
      AC_MSG_NOTICE([The result from running with -qversion was: "$COMPILER_VERSION_OUTPUT"])
      AC_MSG_NOTICE([The result from running with --version was: "$ALT_VERSION_OUTPUT"])
      AC_MSG_ERROR([A $TOOLCHAIN_TYPE compiler is required. Try setting --with-tools-dir.])
    fi
    # Collapse compiler output into a single line
    COMPILER_VERSION_STRING=`$ECHO $COMPILER_VERSION_OUTPUT`
    COMPILER_VERSION_NUMBER=`$ECHO $COMPILER_VERSION_OUTPUT | \
        $SED -e 's/^.*, V\(@<:@1-9@:>@@<:@0-9.@:>@*\).*$/\1/'`
  elif test  "x$TOOLCHAIN_TYPE" = xmicrosoft; then
    # There is no specific version flag, but all output starts with a version string.
    # First line typically looks something like:
    # Microsoft (R) 32-bit C/C++ Optimizing Compiler Version 16.00.40219.01 for 80x86
    # but the compiler name may vary depending on locale.
    COMPILER_VERSION_OUTPUT=`$COMPILER 2>&1 | $HEAD -n 1 | $TR -d '\r'`
    # Check that this is likely to be Microsoft CL.EXE.
    $ECHO "$COMPILER_VERSION_OUTPUT" | $GREP "Microsoft" > /dev/null
    if test $? -ne 0; then
      AC_MSG_NOTICE([The $COMPILER_NAME compiler (located as $COMPILER) does not seem to be the required $TOOLCHAIN_TYPE compiler.])
      AC_MSG_NOTICE([The result from running it was: "$COMPILER_VERSION_OUTPUT"])
      AC_MSG_ERROR([A $TOOLCHAIN_TYPE compiler is required. Try setting --with-tools-dir.])
    fi
    # Collapse compiler output into a single line
    COMPILER_VERSION_STRING=`$ECHO $COMPILER_VERSION_OUTPUT`
    COMPILER_VERSION_NUMBER=`$ECHO $COMPILER_VERSION_OUTPUT | \
        $SED -e 's/^.*ersion.\(@<:@1-9@:>@@<:@0-9.@:>@*\) .*$/\1/'`
  elif test  "x$TOOLCHAIN_TYPE" = xgcc; then
    # gcc --version output typically looks like
    #     gcc (Ubuntu/Linaro 4.8.1-10ubuntu9) 4.8.1
    #     Copyright (C) 2013 Free Software Foundation, Inc.
    #     This is free software; see the source for copying conditions.  There is NO
    #     warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
    COMPILER_VERSION_OUTPUT=`$COMPILER --version 2>&1`
    # Check that this is likely to be GCC.
    $ECHO "$COMPILER_VERSION_OUTPUT" | $GREP "Free Software Foundation" > /dev/null
    if test $? -ne 0; then
      AC_MSG_NOTICE([The $COMPILER_NAME compiler (located as $COMPILER) does not seem to be the required $TOOLCHAIN_TYPE compiler.])
      AC_MSG_NOTICE([The result from running with --version was: "$COMPILER_VERSION"])
      AC_MSG_ERROR([A $TOOLCHAIN_TYPE compiler is required. Try setting --with-tools-dir.])
    fi
    # Remove Copyright and legalese from version string, and
    # collapse into a single line
    COMPILER_VERSION_STRING=`$ECHO $COMPILER_VERSION_OUTPUT | \
        $SED -e 's/ *Copyright .*//'`
    COMPILER_VERSION_NUMBER=`$ECHO $COMPILER_VERSION_OUTPUT | \
        $SED -e 's/^.* \(@<:@1-9@:>@<:@0-9@:>@*\.@<:@0-9.@:>@*\)@<:@^0-9.@:>@.*$/\1/'`
  elif test  "x$TOOLCHAIN_TYPE" = xclang; then
    # clang --version output typically looks like
    #    Apple LLVM version 5.0 (clang-500.2.79) (based on LLVM 3.3svn)
    #    clang version 3.3 (tags/RELEASE_33/final)
    # or
    #    Debian clang version 3.2-7ubuntu1 (tags/RELEASE_32/final) (based on LLVM 3.2)
    #    Target: x86_64-pc-linux-gnu
    #    Thread model: posix
    COMPILER_VERSION_OUTPUT=`$COMPILER --version 2>&1`
    # Check that this is likely to be clang
    $ECHO "$COMPILER_VERSION_OUTPUT" | $GREP "clang" > /dev/null
    if test $? -ne 0; then
      AC_MSG_NOTICE([The $COMPILER_NAME compiler (located as $COMPILER) does not seem to be the required $TOOLCHAIN_TYPE compiler.])
      AC_MSG_NOTICE([The result from running with --version was: "$COMPILER_VERSION_OUTPUT"])
      AC_MSG_ERROR([A $TOOLCHAIN_TYPE compiler is required. Try setting --with-tools-dir.])
    fi
    # Collapse compiler output into a single line
    COMPILER_VERSION_STRING=`$ECHO $COMPILER_VERSION_OUTPUT`
    COMPILER_VERSION_NUMBER=`$ECHO $COMPILER_VERSION_OUTPUT | \
        $SED -e 's/^.* version \(@<:@1-9@:>@@<:@0-9.@:>@*\).*$/\1/'`
  else
      AC_MSG_ERROR([Unknown toolchain type $TOOLCHAIN_TYPE.])
  fi
  # This sets CC_VERSION_NUMBER or CXX_VERSION_NUMBER. (This comment is a grep marker)
  $1_VERSION_NUMBER="$COMPILER_VERSION_NUMBER"
  # This sets CC_VERSION_STRING or CXX_VERSION_STRING. (This comment is a grep marker)
  $1_VERSION_STRING="$COMPILER_VERSION_STRING"

  AC_MSG_NOTICE([Using $TOOLCHAIN_TYPE $COMPILER_NAME compiler version $COMPILER_VERSION_NUMBER @<:@$COMPILER_VERSION_STRING@:>@])
])

# Try to locate the given C or C++ compiler in the path, or otherwise.
#
# $1 = compiler to test (CC or CXX)
# $2 = human readable name of compiler (C or C++)
# $3 = compiler name to search for
AC_DEFUN([TOOLCHAIN_FIND_COMPILER],
[
  COMPILER_NAME=$2
  SEARCH_LIST="$3"

  if test "x[$]$1" != x; then
    # User has supplied compiler name already, always let that override.
    AC_MSG_NOTICE([Will use user supplied compiler $1=[$]$1])
    if test "x`basename [$]$1`" = "x[$]$1"; then
      # A command without a complete path is provided, search $PATH.

      AC_PATH_PROGS(POTENTIAL_$1, [$]$1)
      if test "x$POTENTIAL_$1" != x; then
        $1=$POTENTIAL_$1
      else
        AC_MSG_ERROR([User supplied compiler $1=[$]$1 could not be found])
      fi
    else
      # Otherwise it might already be a complete path
      if test ! -x "[$]$1"; then
        AC_MSG_ERROR([User supplied compiler $1=[$]$1 does not exist])
      fi
    fi
  else
    # No user supplied value. Locate compiler ourselves.

    # If we are cross compiling, assume cross compilation tools follows the
    # cross compilation standard where they are prefixed with the autoconf
    # standard name for the target. For example the binary
    # i686-sun-solaris2.10-gcc will cross compile for i686-sun-solaris2.10.
    # If we are not cross compiling, then the default compiler name will be
    # used.

    $1=
    # If TOOLCHAIN_PATH is set, check for all compiler names in there first
    # before checking the rest of the PATH.
    # FIXME: Now that we prefix the TOOLS_DIR to the PATH in the PRE_DETECTION
    # step, this should not be necessary.
    if test -n "$TOOLCHAIN_PATH"; then
      PATH_save="$PATH"
      PATH="$TOOLCHAIN_PATH"
      AC_PATH_TOOL(TOOLCHAIN_PATH_$1, $SEARCH_LIST)
      $1=$TOOLCHAIN_PATH_$1
      PATH="$PATH_save"
    fi

    # AC_PATH_TOOL can't be run multiple times with the same variable,
    # so create a new name for this run.
    if test "x[$]$1" = x; then
      AC_PATH_TOOL(POTENTIAL_$1, $SEARCH_LIST)
      $1=$POTENTIAL_$1
    fi

    if test "x[$]$1" = x; then
      HELP_MSG_MISSING_DEPENDENCY([devkit])
      AC_MSG_ERROR([Could not find a $COMPILER_NAME compiler. $HELP_MSG])
    fi
  fi

  # Now we have a compiler binary in $1. Make sure it's okay.
  BASIC_FIXUP_EXECUTABLE($1)
  TEST_COMPILER="[$]$1"

  AC_MSG_CHECKING([resolved symbolic links for $1])
  SYMLINK_ORIGINAL="$TEST_COMPILER"
  BASIC_REMOVE_SYMBOLIC_LINKS(SYMLINK_ORIGINAL)
  if test "x$TEST_COMPILER" = "x$SYMLINK_ORIGINAL"; then
    AC_MSG_RESULT([no symlink])
  else
    AC_MSG_RESULT([$SYMLINK_ORIGINAL])

    # We can't handle ccache by gcc wrappers, since we need to know if we're
    # using ccache. Instead ccache usage must be controlled by a configure option.
    COMPILER_BASENAME=`$BASENAME "$SYMLINK_ORIGINAL"`
    if test "x$COMPILER_BASENAME" = "xccache"; then
      AC_MSG_NOTICE([Please use --enable-ccache instead of providing a wrapped compiler.])
      AC_MSG_ERROR([$TEST_COMPILER is a symbolic link to ccache. This is not supported.])
    fi
  fi

  TOOLCHAIN_EXTRACT_COMPILER_VERSION([$1], [$COMPILER_NAME])
])

# Retrieve the linker version number and store it in LD_VERSION_NUMBER
# (as a dotted number), and
# the full version string in LD_VERSION_STRING.
#
# $1 = linker to test (LD or BUILD_LD)
# $2 = human readable name of linker (Linker or BuildLinker)
AC_DEFUN([TOOLCHAIN_EXTRACT_LD_VERSION],
[
  LINKER=[$]$1
  LINKER_NAME="$2"

  if test "x$TOOLCHAIN_TYPE" = xsolstudio; then
    # cc -Wl,-V output typically looks like
    #   ld: Software Generation Utilities - Solaris Link Editors: 5.11-1.2329

    # solstudio cc requires us to have an existing file to pass as argument,
    # but it need not be a syntactically correct C file, so just use
    # ourself. :) The intermediate 'cat' is needed to stop ld from leaving
    # a lingering a.out (!).
    LINKER_VERSION_STRING=`$LD -Wl,-V $TOPDIR/configure 2>&1 | $CAT | $HEAD -n 1 | $SED -e 's/ld: //'`
    # Extract version number
    [ LINKER_VERSION_NUMBER=`$ECHO $LINKER_VERSION_STRING | \
        $SED -e 's/.* \([0-9][0-9]*\.[0-9][0-9]*\)-\([0-9][0-9]*\.[0-9][0-9]*\)/\1.\2/'` ]
  elif test  "x$TOOLCHAIN_TYPE" = xxlc; then
    LINKER_VERSION_STRING="Unknown"
    LINKER_VERSION_NUMBER="0.0"
  elif test  "x$TOOLCHAIN_TYPE" = xmicrosoft; then
    # There is no specific version flag, but all output starts with a version string.
    # First line typically looks something like:
    #   Microsoft (R) Incremental Linker Version 12.00.31101.0
    LINKER_VERSION_STRING=`$LD 2>&1 | $HEAD -n 1 | $TR -d '\r'`
    # Extract version number
    [ LINKER_VERSION_NUMBER=`$ECHO $LINKER_VERSION_STRING | \
        $SED -e 's/.* \([0-9][0-9]*\(\.[0-9][0-9]*\)*\).*/\1/'` ]
  elif test  "x$TOOLCHAIN_TYPE" = xgcc; then
    # gcc -Wl,-version output typically looks like
    #   GNU ld (GNU Binutils for Ubuntu) 2.26.1
    #   Copyright (C) 2015 Free Software Foundation, Inc.
    #   This program is free software; [...]
    LINKER_VERSION_STRING=`$LD -Wl,-version 2>&1 | $HEAD -n 1`
    # Extract version number
    [ LINKER_VERSION_NUMBER=`$ECHO $LINKER_VERSION_STRING | \
        $SED -e 's/.* \([0-9][0-9]*\(\.[0-9][0-9]*\)*\).*/\1/'` ]
  elif test  "x$TOOLCHAIN_TYPE" = xclang; then
    # clang -Wl,-v output typically looks like
    #   @(#)PROGRAM:ld  PROJECT:ld64-305
    #   configured to support archs: armv6 armv7 armv7s arm64 i386 x86_64 x86_64h armv6m armv7k armv7m armv7em (tvOS)
    #   Library search paths: [...]
    # or
    #   GNU ld (GNU Binutils for Ubuntu) 2.26.1

    LINKER_VERSION_STRING=`$LD -Wl,-v 2>&1 | $HEAD -n 1`
    # Check if we're using the GNU ld
    $ECHO "$LINKER_VERSION_STRING" | $GREP "GNU" > /dev/null
    if test $? -eq 0; then
      # Extract version number
      [ LINKER_VERSION_NUMBER=`$ECHO $LINKER_VERSION_STRING | \
          $SED -e 's/.* \([0-9][0-9]*\(\.[0-9][0-9]*\)*\).*/\1/'` ]
    else
      # Extract version number
      [ LINKER_VERSION_NUMBER=`$ECHO $LINKER_VERSION_STRING | \
          $SED -e 's/.*-\([0-9][0-9]*\)/\1/'` ]
    fi
  fi

  $1_VERSION_NUMBER="$LINKER_VERSION_NUMBER"
  $1_VERSION_STRING="$LINKER_VERSION_STRING"

  AC_MSG_NOTICE([Using $TOOLCHAIN_TYPE $LINKER_NAME version $LINKER_VERSION_NUMBER @<:@$LINKER_VERSION_STRING@:>@])
])

# Detect the core components of the toolchain, i.e. the compilers (CC and CXX),
# preprocessor (CPP and CXXCPP), the linker (LD), the assembler (AS) and the
# archiver (AR). Verify that the compilers are correct according to the
# toolchain type.
AC_DEFUN_ONCE([TOOLCHAIN_DETECT_TOOLCHAIN_CORE],
[
  #
  # Setup the compilers (CC and CXX)
  #
  TOOLCHAIN_FIND_COMPILER([CC], [C], $TOOLCHAIN_CC_BINARY)
  # Now that we have resolved CC ourself, let autoconf have its go at it
  AC_PROG_CC([$CC])

  TOOLCHAIN_FIND_COMPILER([CXX], [C++], $TOOLCHAIN_CXX_BINARY)
  # Now that we have resolved CXX ourself, let autoconf have its go at it
  AC_PROG_CXX([$CXX])

  # This is the compiler version number on the form X.Y[.Z]
  AC_SUBST(CC_VERSION_NUMBER)
  AC_SUBST(CXX_VERSION_NUMBER)

  TOOLCHAIN_PREPARE_FOR_VERSION_COMPARISONS

  if test "x$TOOLCHAIN_MINIMUM_VERSION" != x; then
    TOOLCHAIN_CHECK_COMPILER_VERSION(VERSION: $TOOLCHAIN_MINIMUM_VERSION,
        IF_OLDER_THAN: [
          AC_MSG_WARN([You are using $TOOLCHAIN_TYPE older than $TOOLCHAIN_MINIMUM_VERSION. This is not a supported configuration.])
        ]
    )
  fi

  #
  # Setup the preprocessor (CPP and CXXCPP)
  #
  AC_PROG_CPP
  BASIC_FIXUP_EXECUTABLE(CPP)
  AC_PROG_CXXCPP
  BASIC_FIXUP_EXECUTABLE(CXXCPP)

  #
  # Setup the linker (LD)
  #
  if test "x$TOOLCHAIN_TYPE" = xmicrosoft; then
    # In the Microsoft toolchain we have a separate LD command "link".
    # Make sure we reject /usr/bin/link (as determined in CYGWIN_LINK), which is
    # a cygwin program for something completely different.
    AC_CHECK_PROG([LD], [link],[link],,, [$CYGWIN_LINK])
    BASIC_FIXUP_EXECUTABLE(LD)
    # Verify that we indeed succeeded with this trick.
    AC_MSG_CHECKING([if the found link.exe is actually the Visual Studio linker])
    "$LD" --version > /dev/null
    if test $? -eq 0 ; then
      AC_MSG_RESULT([no])
      AC_MSG_ERROR([This is the Cygwin link tool. Please check your PATH and rerun configure.])
    else
      AC_MSG_RESULT([yes])
    fi
    LDCXX="$LD"
    # jaotc being a windows program expects the linker to be supplied with exe suffix.
    LD_JAOTC="$LD$EXE_SUFFIX"
  else
    # All other toolchains use the compiler to link.
    LD="$CC"
    LDCXX="$CXX"
    # jaotc expects 'ld' as the linker rather than the compiler.
    BASIC_CHECK_TOOLS([LD_JAOTC], ld)
    BASIC_FIXUP_EXECUTABLE(LD_JAOTC)
  fi
  AC_SUBST(LD)
  AC_SUBST(LD_JAOTC)
  # FIXME: it should be CXXLD, according to standard (cf CXXCPP)
  AC_SUBST(LDCXX)

  TOOLCHAIN_EXTRACT_LD_VERSION([LD], [linker])
  TOOLCHAIN_PREPARE_FOR_LD_VERSION_COMPARISONS

  if test "x$TOOLCHAIN_MINIMUM_LD_VERSION" != x; then
    TOOLCHAIN_CHECK_LINKER_VERSION(VERSION: $TOOLCHAIN_MINIMUM_LD_VERSION,
        IF_OLDER_THAN: [
          AC_MSG_WARN([You are using a linker older than $TOOLCHAIN_MINIMUM_LD_VERSION. This is not a supported configuration.])
        ]
    )
  fi

  #
  # Setup the assembler (AS)
  #
  if test "x$OPENJDK_TARGET_OS" = xsolaris; then
    BASIC_PATH_PROGS(AS, as)
    BASIC_FIXUP_EXECUTABLE(AS)
    if test "x$AS" = x; then
      AC_MSG_ERROR([Solaris assembler (as) is required. Please install via "pkg install pkg:/developer/assembler".])
    fi
  else
    # FIXME: is this correct for microsoft?
    AS="$CC -c"
  fi
  AC_SUBST(AS)

  #
  # Setup the archiver (AR)
  #
  if test "x$TOOLCHAIN_TYPE" = xmicrosoft; then
    # The corresponding ar tool is lib.exe (used to create static libraries)
    AC_CHECK_PROG([AR], [lib],[lib],,,)
  elif test "x$TOOLCHAIN_TYPE" = xgcc; then
    BASIC_CHECK_TOOLS(AR, ar gcc-ar)
  else
    BASIC_CHECK_TOOLS(AR, ar)
  fi
  BASIC_FIXUP_EXECUTABLE(AR)
])

# Setup additional tools that is considered a part of the toolchain, but not the
# core part. Many of these are highly platform-specific and do not exist,
# and/or are not needed on all platforms.
AC_DEFUN_ONCE([TOOLCHAIN_DETECT_TOOLCHAIN_EXTRA],
[
  if test "x$OPENJDK_TARGET_OS" = "xmacosx"; then
    BASIC_PATH_PROGS(LIPO, lipo)
    BASIC_FIXUP_EXECUTABLE(LIPO)
    BASIC_REQUIRE_PROGS(OTOOL, otool)
    BASIC_FIXUP_EXECUTABLE(OTOOL)
    BASIC_REQUIRE_PROGS(INSTALL_NAME_TOOL, install_name_tool)
    BASIC_FIXUP_EXECUTABLE(INSTALL_NAME_TOOL)
  fi

  if test "x$TOOLCHAIN_TYPE" = xmicrosoft; then
    AC_CHECK_PROG([MT], [mt], [mt],,, [/usr/bin/mt])
    BASIC_FIXUP_EXECUTABLE(MT)
    # Setup the resource compiler (RC)
    AC_CHECK_PROG([RC], [rc], [rc],,, [/usr/bin/rc])
    BASIC_FIXUP_EXECUTABLE(RC)
    AC_CHECK_PROG([DUMPBIN], [dumpbin], [dumpbin],,,)
    BASIC_FIXUP_EXECUTABLE(DUMPBIN)
    # We need to check for 'msbuild.exe' because at the place where we expect to
    # find 'msbuild.exe' there's also a directory called 'msbuild' and configure
    # won't find the 'msbuild.exe' executable in that case (and the
    # 'ac_executable_extensions' is unusable due to performance reasons).
    # Notice that we intentionally don't fix up the path to MSBUILD because we
    # will call it in a DOS shell during freetype detection on Windows (see
    # 'LIB_SETUP_FREETYPE' in "libraries.m4"
    AC_CHECK_PROG([MSBUILD], [msbuild.exe], [msbuild.exe],,,)
  fi

  if test "x$OPENJDK_TARGET_OS" = xsolaris; then
    BASIC_PATH_PROGS(STRIP, strip)
    BASIC_FIXUP_EXECUTABLE(STRIP)
    BASIC_PATH_PROGS(NM, nm)
    BASIC_FIXUP_EXECUTABLE(NM)
    BASIC_PATH_PROGS(GNM, gnm)
    BASIC_FIXUP_EXECUTABLE(GNM)
  elif test "x$OPENJDK_TARGET_OS" != xwindows; then
    # FIXME: we should unify this with the solaris case above.
    BASIC_CHECK_TOOLS(STRIP, strip)
    BASIC_FIXUP_EXECUTABLE(STRIP)
    if test "x$TOOLCHAIN_TYPE" = xgcc; then
      BASIC_CHECK_TOOLS(NM, nm gcc-nm)
    else
      BASIC_CHECK_TOOLS(NM, nm)
    fi
    BASIC_FIXUP_EXECUTABLE(NM)
    GNM="$NM"
    AC_SUBST(GNM)
  fi

  # objcopy is used for moving debug symbols to separate files when
  # full debug symbols are enabled.
  if test "x$OPENJDK_TARGET_OS" = xsolaris || test "x$OPENJDK_TARGET_OS" = xlinux; then
    BASIC_CHECK_TOOLS(OBJCOPY, [gobjcopy objcopy])
    # Only call fixup if objcopy was found.
    if test -n "$OBJCOPY"; then
      BASIC_FIXUP_EXECUTABLE(OBJCOPY)
      if test "x$OPENJDK_BUILD_OS" = xsolaris; then
        # objcopy prior to 2.21.1 on solaris is broken and is not usable.
        # Rewrite objcopy version output to VALID_VERSION or BAD_VERSION.
        # - version number is last blank separate word on first line
        # - version number formats that have been seen:
        #   - <major>.<minor>
        #   - <major>.<minor>.<micro>
        OBJCOPY_VERSION=`$OBJCOPY --version | $HEAD -n 1`
        # The outer [ ] is to prevent m4 from eating the [] in the sed expression.
        [ OBJCOPY_VERSION_CHECK=`$ECHO $OBJCOPY_VERSION | $SED -n \
              -e 's/.* //' \
              -e '/^[01]\./b bad' \
              -e '/^2\./{' \
              -e '  s/^2\.//' \
              -e '  /^[0-9]$/b bad' \
              -e '  /^[0-9]\./b bad' \
              -e '  /^1[0-9]$/b bad' \
              -e '  /^1[0-9]\./b bad' \
              -e '  /^20\./b bad' \
              -e '  /^21\.0$/b bad' \
              -e '  /^21\.0\./b bad' \
              -e '}' \
              -e ':good' \
              -e 's/.*/VALID_VERSION/p' \
              -e 'q' \
              -e ':bad' \
              -e 's/.*/BAD_VERSION/p' \
              -e 'q'` ]
        if test "x$OBJCOPY_VERSION_CHECK" = xBAD_VERSION; then
          OBJCOPY=
          AC_MSG_WARN([Ignoring found objcopy since it is broken (prior to 2.21.1). No debug symbols will be generated.])
          AC_MSG_NOTICE([objcopy reports version $OBJCOPY_VERSION])
          AC_MSG_NOTICE([Note: patch 149063-01 or newer contains the correct Solaris 10 SPARC version])
          AC_MSG_NOTICE([Note: patch 149064-01 or newer contains the correct Solaris 10 X86 version])
          AC_MSG_NOTICE([Note: Solaris 11 Update 1 contains the correct version])
        fi
      fi
    fi
  fi

  BASIC_CHECK_TOOLS(OBJDUMP, [gobjdump objdump])
  if test "x$OBJDUMP" != x; then
    # Only used for compare.sh; we can live without it. BASIC_FIXUP_EXECUTABLE
    # bails if argument is missing.
    BASIC_FIXUP_EXECUTABLE(OBJDUMP)
  fi

  case $TOOLCHAIN_TYPE in
    gcc|clang|solstudio)
      BASIC_CHECK_TOOLS(CXXFILT, [c++filt])
      BASIC_CHECK_NONEMPTY(CXXFILT)
      BASIC_FIXUP_EXECUTABLE(CXXFILT)
      ;;
  esac
])

# Setup the build tools (i.e, the compiler and linker used to build programs
# that should be run on the build platform, not the target platform, as a build
# helper). Since the non-cross-compile case uses the normal, target compilers
# for this, we can only do this after these have been setup.
AC_DEFUN_ONCE([TOOLCHAIN_SETUP_BUILD_COMPILERS],
[
  if test "x$COMPILE_TYPE" = "xcross"; then
    # Now we need to find a C/C++ compiler that can build executables for the
    # build platform. We can't use the AC_PROG_CC macro, since it can only be
    # used once. Also, we need to do this without adding a tools dir to the
    # path, otherwise we might pick up cross-compilers which don't use standard
    # naming.

    OLDPATH="$PATH"

    AC_ARG_WITH(build-devkit, [AS_HELP_STRING([--with-build-devkit],
        [Devkit to use for the build platform toolchain])])
    if test "x$with_build_devkit" = "xyes"; then
      AC_MSG_ERROR([--with-build-devkit must have a value])
    elif test -n "$with_build_devkit"; then
      if test ! -d "$with_build_devkit"; then
        AC_MSG_ERROR([--with-build-devkit points to non existing dir: $with_build_devkit])
      else
        BASIC_FIXUP_PATH([with_build_devkit])
        BUILD_DEVKIT_ROOT="$with_build_devkit"
        # Check for a meta data info file in the root of the devkit
        if test -f "$BUILD_DEVKIT_ROOT/devkit.info"; then
          # Process devkit.info so that existing devkit variables are not
          # modified by this
          $SED -e "s/^DEVKIT_/BUILD_DEVKIT_/g" \
              -e "s/\$DEVKIT_ROOT/\$BUILD_DEVKIT_ROOT/g" \
              -e "s/\$host/\$build/g" \
              $BUILD_DEVKIT_ROOT/devkit.info \
              > $CONFIGURESUPPORT_OUTPUTDIR/build-devkit.info
          . $CONFIGURESUPPORT_OUTPUTDIR/build-devkit.info
          # This potentially sets the following:
          # A descriptive name of the devkit
          BASIC_EVAL_DEVKIT_VARIABLE([BUILD_DEVKIT_NAME])
          # Corresponds to --with-extra-path
          BASIC_EVAL_DEVKIT_VARIABLE([BUILD_DEVKIT_EXTRA_PATH])
          # Corresponds to --with-toolchain-path
          BASIC_EVAL_DEVKIT_VARIABLE([BUILD_DEVKIT_TOOLCHAIN_PATH])
          # Corresponds to --with-sysroot
          BASIC_EVAL_DEVKIT_VARIABLE([BUILD_DEVKIT_SYSROOT])
          # Skip the Window specific parts
        fi

        AC_MSG_CHECKING([for build platform devkit])
        if test "x$BUILD_DEVKIT_NAME" != x; then
          AC_MSG_RESULT([$BUILD_DEVKIT_NAME in $BUILD_DEVKIT_ROOT])
        else
          AC_MSG_RESULT([$BUILD_DEVKIT_ROOT])
        fi

        BUILD_SYSROOT="$BUILD_DEVKIT_SYSROOT"

         # Fallback default of just /bin if DEVKIT_PATH is not defined
        if test "x$BUILD_DEVKIT_TOOLCHAIN_PATH" = x; then
          BUILD_DEVKIT_TOOLCHAIN_PATH="$BUILD_DEVKIT_ROOT/bin"
        fi
        PATH="$BUILD_DEVKIT_TOOLCHAIN_PATH:$BUILD_DEVKIT_EXTRA_PATH"
      fi
    fi

    # FIXME: we should list the discovered compilers as an exclude pattern!
    # If we do that, we can do this detection before POST_DETECTION, and still
    # find the build compilers in the tools dir, if needed.
    if test "x$OPENJDK_BUILD_OS" = xmacosx; then
      BASIC_REQUIRE_PROGS(BUILD_CC, [clang cl cc gcc])
      BASIC_REQUIRE_PROGS(BUILD_CXX, [clang++ cl CC g++])
    else
      BASIC_REQUIRE_PROGS(BUILD_CC, [cl cc gcc])
      BASIC_REQUIRE_PROGS(BUILD_CXX, [cl CC g++])
    fi
    BASIC_FIXUP_EXECUTABLE(BUILD_CC)
    BASIC_FIXUP_EXECUTABLE(BUILD_CXX)
    BASIC_PATH_PROGS(BUILD_NM, nm gcc-nm)
    BASIC_FIXUP_EXECUTABLE(BUILD_NM)
    BASIC_PATH_PROGS(BUILD_AR, ar gcc-ar)
    BASIC_FIXUP_EXECUTABLE(BUILD_AR)
    BASIC_PATH_PROGS(BUILD_OBJCOPY, objcopy)
    BASIC_FIXUP_EXECUTABLE(BUILD_OBJCOPY)
    BASIC_PATH_PROGS(BUILD_STRIP, strip)
    BASIC_FIXUP_EXECUTABLE(BUILD_STRIP)
    # Assume the C compiler is the assembler
    BUILD_AS="$BUILD_CC -c"
    # Just like for the target compiler, use the compiler as linker
    BUILD_LD="$BUILD_CC"
    BUILD_LDCXX="$BUILD_CXX"

    PATH="$OLDPATH"

    TOOLCHAIN_EXTRACT_COMPILER_VERSION(BUILD_CC, [BuildC])
    TOOLCHAIN_EXTRACT_COMPILER_VERSION(BUILD_CXX, [BuildC++])
    TOOLCHAIN_PREPARE_FOR_VERSION_COMPARISONS([BUILD_], [OPENJDK_BUILD_])
    TOOLCHAIN_EXTRACT_LD_VERSION(BUILD_LD, [build linker])
    TOOLCHAIN_PREPARE_FOR_LD_VERSION_COMPARISONS([BUILD_], [OPENJDK_BUILD_])
  else
    # If we are not cross compiling, use the normal target compilers for
    # building the build platform executables.
    BUILD_CC="$CC"
    BUILD_CXX="$CXX"
    BUILD_LD="$LD"
    BUILD_LDCXX="$LDCXX"
    BUILD_NM="$NM"
    BUILD_AS="$AS"
    BUILD_OBJCOPY="$OBJCOPY"
    BUILD_STRIP="$STRIP"
    BUILD_AR="$AR"

    TOOLCHAIN_PREPARE_FOR_VERSION_COMPARISONS([], [OPENJDK_BUILD_])
    TOOLCHAIN_PREPARE_FOR_LD_VERSION_COMPARISONS([BUILD_], [OPENJDK_BUILD_])
  fi

  AC_SUBST(BUILD_CC)
  AC_SUBST(BUILD_CXX)
  AC_SUBST(BUILD_LD)
  AC_SUBST(BUILD_LDCXX)
  AC_SUBST(BUILD_NM)
  AC_SUBST(BUILD_AS)
  AC_SUBST(BUILD_AR)
])

# Do some additional checks on the detected tools.
AC_DEFUN_ONCE([TOOLCHAIN_MISC_CHECKS],
[
  # The package path is used only on macosx?
  # FIXME: clean this up, and/or move it elsewhere.
  PACKAGE_PATH=/opt/local
  AC_SUBST(PACKAGE_PATH)

  # Check for extra potential brokenness.
  if test  "x$TOOLCHAIN_TYPE" = xmicrosoft; then
    # On Windows, double-check that we got the right compiler.
    CC_VERSION_OUTPUT=`$CC 2>&1 | $HEAD -n 1 | $TR -d '\r'`
    COMPILER_CPU_TEST=`$ECHO $CC_VERSION_OUTPUT | $SED -n "s/^.* \(.*\)$/\1/p"`
    if test "x$OPENJDK_TARGET_CPU" = "xx86"; then
      if test "x$COMPILER_CPU_TEST" != "x80x86" -a "x$COMPILER_CPU_TEST" != "xx86"; then
        AC_MSG_ERROR([Target CPU mismatch. We are building for $OPENJDK_TARGET_CPU but CL is for "$COMPILER_CPU_TEST"; expected "80x86" or "x86".])
      fi
    elif test "x$OPENJDK_TARGET_CPU" = "xx86_64"; then
      if test "x$COMPILER_CPU_TEST" != "xx64"; then
        AC_MSG_ERROR([Target CPU mismatch. We are building for $OPENJDK_TARGET_CPU but CL is for "$COMPILER_CPU_TEST"; expected "x64".])
      fi
    fi
  fi

  if test "x$TOOLCHAIN_TYPE" = xgcc; then
    # If this is a --hash-style=gnu system, use --hash-style=both, why?
    HAS_GNU_HASH=`$CC -dumpspecs 2>/dev/null | $GREP 'hash-style=gnu'`
    # This is later checked when setting flags.
  fi

  if test "x$TOOLCHAIN_TYPE" = xgcc || test "x$TOOLCHAIN_TYPE" = xclang; then
    # Check if linker has -z noexecstack.
    HAS_NOEXECSTACK=`$CC -Wl,--help 2>/dev/null | $GREP 'z noexecstack'`
    # This is later checked when setting flags.
  fi

  # Setup hotspot lecagy names for toolchains
  HOTSPOT_TOOLCHAIN_TYPE=$TOOLCHAIN_TYPE
  if test "x$TOOLCHAIN_TYPE" = xclang; then
    HOTSPOT_TOOLCHAIN_TYPE=gcc
  elif test "x$TOOLCHAIN_TYPE" = xsolstudio; then
    HOTSPOT_TOOLCHAIN_TYPE=sparcWorks
  elif test "x$TOOLCHAIN_TYPE" = xmicrosoft; then
    HOTSPOT_TOOLCHAIN_TYPE=visCPP
  fi
  AC_SUBST(HOTSPOT_TOOLCHAIN_TYPE)
])

# Setup the JTReg Regression Test Harness.
AC_DEFUN_ONCE([TOOLCHAIN_SETUP_JTREG],
[
  AC_ARG_WITH(jtreg, [AS_HELP_STRING([--with-jtreg],
      [Regression Test Harness @<:@probed@:>@])])

  if test "x$with_jtreg" = xno; then
    # jtreg disabled
    AC_MSG_CHECKING([for jtreg test harness])
    AC_MSG_RESULT([no, disabled])
  elif test "x$with_jtreg" != xyes && test "x$with_jtreg" != x; then
    # An explicit path is specified, use it.
    JT_HOME="$with_jtreg"
    BASIC_FIXUP_PATH([JT_HOME])
    if test ! -d "$JT_HOME"; then
      AC_MSG_ERROR([jtreg home directory from --with-jtreg=$with_jtreg does not exist])
    fi

    if test ! -e "$JT_HOME/lib/jtreg.jar"; then
      AC_MSG_ERROR([jtreg home directory from --with-jtreg=$with_jtreg is not a valid jtreg home])
    fi

    JTREGEXE="$JT_HOME/bin/jtreg"
    if test ! -x "$JTREGEXE"; then
      AC_MSG_ERROR([jtreg home directory from --with-jtreg=$with_jtreg does not contain valid jtreg executable])
    fi

    AC_MSG_CHECKING([for jtreg test harness])
    AC_MSG_RESULT([$JT_HOME])
  else
    # Try to locate jtreg
    if test "x$JT_HOME" != x; then
      # JT_HOME set in environment, use it
      if test ! -d "$JT_HOME"; then
        AC_MSG_WARN([Ignoring JT_HOME pointing to invalid directory: $JT_HOME])
        JT_HOME=
      else
        if test ! -e "$JT_HOME/lib/jtreg.jar"; then
          AC_MSG_WARN([Ignoring JT_HOME which is not a valid jtreg home: $JT_HOME])
          JT_HOME=
        elif test ! -x "$JT_HOME/bin/jtreg"; then
          AC_MSG_WARN([Ignoring JT_HOME which does not contain valid jtreg executable: $JT_HOME])
          JT_HOME=
        else
          JTREGEXE="$JT_HOME/bin/jtreg"
          AC_MSG_NOTICE([Located jtreg using JT_HOME from environment])
        fi
      fi
    fi

    if test "x$JT_HOME" = x; then
      # JT_HOME is not set in environment, or was deemed invalid.
      # Try to find jtreg on path
      BASIC_PATH_PROGS(JTREGEXE, jtreg)
      if test "x$JTREGEXE" != x; then
        # That's good, now try to derive JT_HOME
        JT_HOME=`(cd $($DIRNAME $JTREGEXE)/.. && pwd)`
        if test ! -e "$JT_HOME/lib/jtreg.jar"; then
          AC_MSG_WARN([Ignoring jtreg from path since a valid jtreg home cannot be found])
          JT_HOME=
          JTREGEXE=
        else
          AC_MSG_NOTICE([Located jtreg using jtreg executable in path])
        fi
      fi
    fi

    AC_MSG_CHECKING([for jtreg test harness])
    if test "x$JT_HOME" != x; then
      AC_MSG_RESULT([$JT_HOME])
    else
      AC_MSG_RESULT([no, not found])

      if test "x$with_jtreg" = xyes; then
        AC_MSG_ERROR([--with-jtreg was specified, but no jtreg found.])
      fi
    fi
  fi

  BASIC_FIXUP_EXECUTABLE(JTREGEXE)
  BASIC_FIXUP_PATH(JT_HOME)
  AC_SUBST(JT_HOME)
  AC_SUBST(JTREGEXE)
])

# Setup the JIB dependency resolver
AC_DEFUN_ONCE([TOOLCHAIN_SETUP_JIB],
[
  AC_ARG_WITH(jib, [AS_HELP_STRING([--with-jib],
      [Jib dependency management tool @<:@not used@:>@])])

  if test "x$with_jib" = xno || test "x$with_jib" = x; then
    # jib disabled
    AC_MSG_CHECKING([for jib])
    AC_MSG_RESULT(no)
  elif test "x$with_jib" = xyes; then
    AC_MSG_ERROR([Must supply a value to --with-jib])
  else
    JIB_HOME="${with_jib}"
    AC_MSG_CHECKING([for jib])
    AC_MSG_RESULT(${JIB_HOME})
    if test ! -d "${JIB_HOME}"; then
      AC_MSG_ERROR([--with-jib must be a directory])
    fi
    JIB_JAR=$(ls ${JIB_HOME}/lib/jib-*.jar)
    if test ! -f "${JIB_JAR}"; then
      AC_MSG_ERROR([Could not find jib jar file in ${JIB_HOME}])
    fi
  fi

  AC_SUBST(JIB_HOME)
])