# A few convenience macros for Mesa, mostly to keep all the platform

# specifics out of configure.ac.

# MESA_PIC_FLAGS()

#

# Find out whether to build PIC code using the option --enable-pic and

# the configure enable_static/enable_shared settings. If PIC is needed,

# figure out the necessary flags for the platform and compiler.

#

# The platform checks have been shamelessly taken from libtool and

# stripped down to just what's needed for Mesa. See _LT_COMPILER_PIC in

# /usr/share/aclocal/libtool.m4 or

# http://git.savannah.gnu.org/gitweb/?p=libtool.git;a=blob;f=libltdl/m4/libtool.m4;hb=HEAD

#

AC_DEFUN([MESA_PIC_FLAGS],

[AC_REQUIRE([AC_PROG_CC])dnl

AC_ARG_VAR([PIC_FLAGS], [compiler flags for PIC code])

AC_ARG_ENABLE([pic],

    [AS_HELP_STRING([--disable-pic],

        [compile PIC objects @<:@default=enabled for shared builds

        on supported platforms@:>@])],

    [enable_pic="$enableval"

    test "x$enable_pic" = x && enable_pic=auto],

    [enable_pic=auto])

# disable PIC by default for static builds

if test "$enable_pic" = auto && test "$enable_static" = yes; then

    enable_pic=no

fi

# if PIC hasn't been explicitly disabled, try to figure out the flags

if test "$enable_pic" != no; then

    AC_MSG_CHECKING([for $CC option to produce PIC])

    # allow the user's flags to override

    if test "x$PIC_FLAGS" = x; then

        # see if we're using GCC

        if test "x$GCC" = xyes; then

            case "$host_os" in

            aix*|beos*|cygwin*|irix5*|irix6*|osf3*|osf4*|osf5*)

                # PIC is the default for these OSes.

                ;;

            mingw*|os2*|pw32*)

                # This hack is so that the source file can tell whether

                # it is being built for inclusion in a dll (and should

                # export symbols for example).

                PIC_FLAGS="-DDLL_EXPORT"

                ;;

            darwin*|rhapsody*)

                # PIC is the default on this platform

                # Common symbols not allowed in MH_DYLIB files

                PIC_FLAGS="-fno-common"

                ;;

            hpux*)

                # PIC is the default for IA64 HP-UX and 64-bit HP-UX,

                # but not for PA HP-UX.

                case $host_cpu in

                hppa*64*|ia64*)

                    ;;

                *)

                    PIC_FLAGS="-fPIC"

                    ;;

                esac

                ;;

            *)

                # Everyone else on GCC uses -fPIC

                PIC_FLAGS="-fPIC"

                ;;

            esac

        else # !GCC

            case "$host_os" in

            hpux9*|hpux10*|hpux11*)

                # PIC is the default for IA64 HP-UX and 64-bit HP-UX,

                # but not for PA HP-UX.

                case "$host_cpu" in

                hppa*64*|ia64*)

                    # +Z the default

                    ;;

                *)

                    PIC_FLAGS="+Z"

                    ;;

                esac

                ;;

            linux*|k*bsd*-gnu)

                case `basename "$CC"` in

                icc*|ecc*|ifort*)

                    PIC_FLAGS="-KPIC"

                    ;;

                pgcc*|pgf77*|pgf90*|pgf95*)

                    # Portland Group compilers (*not* the Pentium gcc

                    # compiler, which looks to be a dead project)

                    PIC_FLAGS="-fpic"

                    ;;

                ccc*)

                    # All Alpha code is PIC.

                    ;;

                xl*)

                    # IBM XL C 8.0/Fortran 10.1 on PPC

                    PIC_FLAGS="-qpic"

                    ;;

                *)

                    case `$CC -V 2>&1 | sed 5q` in

                    *Sun\ C*|*Sun\ F*)

                        # Sun C 5.9 or Sun Fortran

                        PIC_FLAGS="-KPIC"

                        ;;

                    esac

                esac

                ;;

            solaris*)

                PIC_FLAGS="-KPIC"

                ;;

            sunos4*)

                PIC_FLAGS="-PIC"

                ;;

            esac

        fi # GCC

    fi # PIC_FLAGS

    AC_MSG_RESULT([$PIC_FLAGS])

fi

AC_SUBST([PIC_FLAGS])

])# MESA_PIC_FLAGS