# This macro set originally copied from Open MPI:

# Copyright © 2004-2005 The Trustees of Indiana University and Indiana

#                         University Research and Technology

#                         Corporation.  All rights reserved.

# Copyright © 2004-2005 The University of Tennessee and The University

#                         of Tennessee Research Foundation.  All rights

#                         reserved.

# Copyright © 2004-2007 High Performance Computing Center Stuttgart,

#                         University of Stuttgart.  All rights reserved.

# Copyright © 2004-2005 The Regents of the University of California.

#                         All rights reserved.

# Copyright © 2006-2007 Cisco Systems, Inc.  All rights reserved.

# and renamed/modified for hwloc:

# Copyright © 2009 Inria.  All rights reserved.

# Copyright © 2009-2010 Université Bordeaux

# Copyright © 2010-2012 Cisco Systems, Inc.  All rights reserved.

# See COPYING in top-level directory.

#

# Redistribution and use in source and binary forms, with or without

# modification, are permitted provided that the following conditions are

# met:

#

# - Redistributions of source code must retain the above copyright

#   notice, this list of conditions and the following disclaimer.

#

# - Redistributions in binary form must reproduce the above copyright

#   notice, this list of conditions and the following disclaimer listed

#   in this license in the documentation and/or other materials

#   provided with the distribution.

#

# - Neither the name of the copyright holders nor the names of its

#   contributors may be used to endorse or promote products derived from

#   this software without specific prior written permission.

#

# The copyright holders provide no reassurances that the source code

# provided does not infringe any patent, copyright, or any other

# intellectual property rights of third parties.  The copyright holders

# disclaim any liability to any recipient for claims brought against

# recipient by any third party for infringement of that parties

# intellectual property rights.

#

# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR

# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT

# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

#

# _HWLOC_CHECK_VISIBILITY

# --------------------------------------------------------

AC_DEFUN([_HWLOC_CHECK_VISIBILITY],[

    # Be safe for systems that have ancient Autoconf's (e.g., RHEL5)

    m4_ifdef([AC_PROG_GREP],

             [AC_REQUIRE([AC_PROG_GREP])],

             [GREP=grep])

    # Check if the compiler has support for visibility, like some

    # versions of gcc, icc, Sun Studio cc.

    AC_ARG_ENABLE(visibility,

        AC_HELP_STRING([--enable-visibility],

            [enable visibility feature of certain compilers/linkers (default: enabled on platforms that support it)]))

    case ${target} in

        *-*-aix*|*-*-mingw*|*-*-cygwin*|*-*-hpux*)

            enable_visibility=no

            ;;

    esac

    hwloc_visibility_define=0

    hwloc_msg="whether to enable symbol visibility"

    if test "$enable_visibility" = "no"; then

        AC_MSG_CHECKING([$hwloc_msg])

        AC_MSG_RESULT([no (disabled)])

    else

        CFLAGS_orig=$CFLAGS

        hwloc_add=

        case "$hwloc_c_vendor" in

        sun)

            # Check using Sun Studio -xldscope=hidden flag

            hwloc_add=-xldscope=hidden

            CFLAGS="$CFLAGS_orig $hwloc_add -errwarn=%all"

            ;;

        *)

            # Check using -fvisibility=hidden

            hwloc_add=-fvisibility=hidden

            CFLAGS="$CFLAGS_orig $hwloc_add -Werror"

            ;;

        esac

        AC_MSG_CHECKING([if $CC supports $hwloc_add])

        AC_LINK_IFELSE([AC_LANG_PROGRAM([[

            #include <stdio.h>

            __attribute__((visibility("default"))) int foo;

            ]],[[fprintf(stderr, "Hello, world\n");]])],

            [AS_IF([test -s conftest.err],

                   [$GREP -iq visibility conftest.err

                    # If we find "visibility" in the stderr, then

                    # assume it doesn't work

                    AS_IF([test "$?" = "0"], [hwloc_add=])])

            ], [hwloc_add=])

        AS_IF([test "$hwloc_add" = ""],

              [AC_MSG_RESULT([no])],

              [AC_MSG_RESULT([yes])])

        CFLAGS=$CFLAGS_orig

        HWLOC_VISIBILITY_CFLAGS=$hwloc_add

        if test "$hwloc_add" != "" ; then

            hwloc_visibility_define=1

            AC_MSG_CHECKING([$hwloc_msg])

            AC_MSG_RESULT([yes (via $hwloc_add)])

        elif test "$enable_visibility" = "yes"; then

            AC_MSG_ERROR([Symbol visibility support requested but compiler does not seem to support it.  Aborting])

        else

            AC_MSG_CHECKING([$hwloc_msg])

            AC_MSG_RESULT([no (unsupported)])

        fi

        unset hwloc_add

    fi

    AC_DEFINE_UNQUOTED([HWLOC_C_HAVE_VISIBILITY], [$hwloc_visibility_define],

            [Whether C compiler supports symbol visibility or not])

])