if test x"${no_tk}" = x ; then
	# we reset no_tk in case something fails here
	no_tk=true
	AC_ARG_WITH(tk,
	    AS_HELP_STRING([--with-tk],
		[directory containing tk configuration (tkConfig.sh)]),
	    [with_tkconfig="${withval}"])
	AC_ARG_WITH(tk8,
	    AS_HELP_STRING([--with-tk8],
		[Compile for Tk8 in Tk9 environment]),
	    [with_tk8="${withval}"])
	AC_MSG_CHECKING([for Tk configuration])
	AC_CACHE_VAL(ac_cv_c_tkconfig,[

	    # First check to see if --with-tkconfig was specified.
	    if test x"${with_tkconfig}" != x ; then
		case "${with_tkconfig}" in
		    */tkConfig.sh )

		    ia64)
			MACHINE="IA64"
			;;
		esac
	    fi

	    if test "$GCC" != "yes" ; then
	        if test "${SHARED_BUILD}" = "0" ; then
		if test "${SHARED_BUILD}" = "0" ; then
		    runtime=-MT
	        else
		else
		    runtime=-MD
	        fi
	        case "x`echo \${VisualStudioVersion}`" in
	            x1[[4-9]]*)
		        lflags="${lflags} -nodefaultlib:libucrt.lib"
		        TEA_ADD_LIBS([ucrt.lib])
	            ;;
	            *)
	            ;;
	        esac
		fi
		case "x`echo \${VisualStudioVersion}`" in
		    x1[[4-9]]*)
			lflags="${lflags} -nodefaultlib:libucrt.lib"
			TEA_ADD_LIBS([ucrt.lib])
		    ;;
		    *)
		    ;;
		esac

		if test "$do64bit" != "no" ; then
		    CC="cl.exe"
		    RC="rc.exe"
		    lflags="${lflags} -nologo -MACHINE:${MACHINE} "
		    LINKBIN="link.exe"
		    CFLAGS_DEBUG="-nologo -Zi -Od -W3 ${runtime}d"

		# AIX requires the _r compiler when gcc isn't being used
		case "${CC}" in
		    *_r|*_r\ *)
			# ok ...
			;;
		    *)
			# Make sure only first arg gets _r
		    	CC=`echo "$CC" | sed -e 's/^\([[^ ]]*\)/\1_r/'`
			CC=`echo "$CC" | sed -e 's/^\([[^ ]]*\)/\1_r/'`
			;;
		esac
		AC_MSG_RESULT([Using $CC for compiling with threads])
	    ])
	    LIBS="$LIBS -lc"
	    SHLIB_CFLAGS=""
	    SHLIB_SUFFIX=".so"

	    AS_IF([test $doRpath = yes], [
		CC_SEARCH_FLAGS='"-Wl,-rpath,${LIB_RUNTIME_DIR}"'
		LD_SEARCH_FLAGS='-rpath "${LIB_RUNTIME_DIR}"'])

	    # Check to enable 64-bit flags for compiler/linker

	    AS_IF([test "$do64bit" = yes], [
	        AS_IF([test "$GCC" = yes], [
	            AC_MSG_WARN([64bit mode not supported by gcc])
	        ], [
	            do64bit_ok=yes
	            SHLIB_LD="ld -64 -shared -rdata_shared"
	            CFLAGS="$CFLAGS -64"
	            LDFLAGS_ARCH="-64"
	        ])
		AS_IF([test "$GCC" = yes], [
		    AC_MSG_WARN([64bit mode not supported by gcc])
		], [
		    do64bit_ok=yes
		    SHLIB_LD="ld -64 -shared -rdata_shared"
		    CFLAGS="$CFLAGS -64"
		    LDFLAGS_ARCH="-64"
		])
	    ])
	    ;;
	Linux*|GNU*|NetBSD-Debian|DragonFly-*|FreeBSD-*)
	    SHLIB_CFLAGS="-fPIC"
	    SHLIB_SUFFIX=".so"

	    # TEA specific:

		# Check for combined 32-bit and 64-bit fat build
		AS_IF([echo "$CFLAGS " |grep -E -q -- '-arch (ppc64|x86_64) ' \
		    && echo "$CFLAGS " |grep -E -q -- '-arch (ppc|i386) '], [
		    fat_32_64=yes])
	    ])
	    # TEA specific: use LDFLAGS_DEFAULT instead of LDFLAGS
	    SHLIB_LD='${CC} -dynamiclib ${CFLAGS} ${LDFLAGS_DEFAULT}'
	    AC_CACHE_CHECK([if ld accepts -single_module flag], tcl_cv_ld_single_module, [
		hold_ldflags=$LDFLAGS
		LDFLAGS="$LDFLAGS -dynamiclib -Wl,-single_module"
		AC_LINK_IFELSE([AC_LANG_PROGRAM([[]], [[int i;]])],
			[tcl_cv_ld_single_module=yes],[tcl_cv_ld_single_module=no])
		LDFLAGS=$hold_ldflags])
	    AS_IF([test $tcl_cv_ld_single_module = yes], [
		SHLIB_LD="${SHLIB_LD} -Wl,-single_module"
	    ])
	    # TEA specific: link shlib with current and compatibility version flags
	    vers=`echo ${PACKAGE_VERSION} | sed -e 's/^\([[0-9]]\{1,5\}\)\(\(\.[[0-9]]\{1,3\}\)\{0,2\}\).*$/\1\2/p' -e d`
	    SHLIB_LD="${SHLIB_LD} -current_version ${vers:-0} -compatibility_version ${vers:-0}"
	    SHLIB_SUFFIX=".dylib"
	    LDFLAGS="$LDFLAGS -headerpad_max_install_names"
	    AC_CACHE_CHECK([if ld accepts -search_paths_first flag],
		    tcl_cv_ld_search_paths_first, [

	    AC_DEFINE(_OE_SOCKETS, 1,	# needed in sys/socket.h
		[Should OS/390 do the right thing with sockets?])
	    ;;
	OSF1-V*)
	    # Digital OSF/1
	    SHLIB_CFLAGS=""
	    AS_IF([test "$SHARED_BUILD" = 1], [
	        SHLIB_LD='ld -shared -expect_unresolved "*"'
		SHLIB_LD='ld -shared -expect_unresolved "*"'
	    ], [
	        SHLIB_LD='ld -non_shared -expect_unresolved "*"'
		SHLIB_LD='ld -non_shared -expect_unresolved "*"'
	    ])
	    SHLIB_SUFFIX=".so"
	    AS_IF([test $doRpath = yes], [
		CC_SEARCH_FLAGS='"-Wl,-rpath,${LIB_RUNTIME_DIR}"'
		LD_SEARCH_FLAGS='-rpath ${LIB_RUNTIME_DIR}'])
	    AS_IF([test "$GCC" = yes], [CFLAGS="$CFLAGS -mieee"], [
		CFLAGS="$CFLAGS -DHAVE_TZSET -std1 -ieee"])

	    # Some UNIX_SV* systems (unixware 1.1.2 for example) have linkers
	    # that don't grok the -Bexport option.  Test that it does.
	    AC_CACHE_CHECK([for ld accepts -Bexport flag], tcl_cv_ld_Bexport, [
		hold_ldflags=$LDFLAGS
		LDFLAGS="$LDFLAGS -Wl,-Bexport"
		AC_LINK_IFELSE([AC_LANG_PROGRAM([[]], [[int i;]])],
			[tcl_cv_ld_Bexport=yes],[tcl_cv_ld_Bexport=no])
	        LDFLAGS=$hold_ldflags])
		LDFLAGS=$hold_ldflags])
	    AS_IF([test $tcl_cv_ld_Bexport = yes], [
		LDFLAGS="$LDFLAGS -Wl,-Bexport"
	    ])
	    CC_SEARCH_FLAGS=""
	    LD_SEARCH_FLAGS=""
	    ;;
    esac

	AC_CACHE_VAL(tcl_cv_type_off64_t,[
	    AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <sys/types.h>]], [[off64_t offset;
]])],
		[tcl_cv_type_off64_t=yes], [tcl_cv_type_off64_t=no])])
	dnl Define HAVE_TYPE_OFF64_T only when the off64_t type and the
	dnl functions lseek64 and open64 are defined.
	if test "x${tcl_cv_type_off64_t}" = "xyes" && \
	        test "x${ac_cv_func_lseek64}" = "xyes" && \
	        test "x${ac_cv_func_open64}" = "xyes" ; then
		test "x${ac_cv_func_lseek64}" = "xyes" && \
		test "x${ac_cv_func_open64}" = "xyes" ; then
	    AC_DEFINE(HAVE_TYPE_OFF64_T, 1, [Is off64_t in <sys/types.h>?])
	    AC_MSG_RESULT([yes])
	else
	    AC_MSG_RESULT([no])
	fi
    fi
])

    PACKAGE_LIB_PREFIX9="${PACKAGE_LIB_PREFIX}tcl9"
    if test "${TCL_MAJOR_VERSION}" -gt 8 -a x"${with_tcl8}" = x; then
	PACKAGE_LIB_PREFIX="${PACKAGE_LIB_PREFIX9}"
    else
	PACKAGE_LIB_PREFIX="${PACKAGE_LIB_PREFIX8}"
	AC_DEFINE(TCL_MAJOR_VERSION, 8, [Compile for Tcl8?])
    fi
    if test "${TCL_MAJOR_VERSION}" -gt 8 -a x"${with_tk8}" != x; then
	AC_DEFINE(TK_MAJOR_VERSION, 8, [Compile for Tk8?])
    fi
    if test "${TEA_PLATFORM}" = "windows" ; then
	if test "${SHARED_BUILD}" = "1" ; then
	    # We force the unresolved linking of symbols that are really in
	    # the private libraries of Tcl and Tk.
	    if test x"${TK_BIN_DIR}" != x ; then
		SHLIB_LD_LIBS="${SHLIB_LD_LIBS} \"`${CYGPATH} ${TK_BIN_DIR}/${TK_STUB_LIB_FILE}`\""
	    fi

	# We want to ensure these are substituted so as not to require
	# any *_NATIVE vars be defined in the Makefile
	TCL_INCLUDES="-I${TCL_GENERIC_DIR_NATIVE} -I${TCL_PLATFORM_DIR_NATIVE}"
	if test "`uname -s`" = "Darwin"; then
	    # If Tcl was built as a framework, attempt to use
	    # the framework's Headers and PrivateHeaders directories
	    case ${TCL_DEFS} in
	    	*TCL_FRAMEWORK*)
		*TCL_FRAMEWORK*)
		    if test -d "${TCL_BIN_DIR}/Headers" -a \
			    -d "${TCL_BIN_DIR}/PrivateHeaders"; then
			TCL_INCLUDES="-I\"${TCL_BIN_DIR}/Headers\" -I\"${TCL_BIN_DIR}/PrivateHeaders\" ${TCL_INCLUDES}"
		    else
			TCL_INCLUDES="${TCL_INCLUDES} ${TCL_INCLUDE_SPEC} `echo "${TCL_INCLUDE_SPEC}" | sed -e 's/Headers/PrivateHeaders/'`"
		    fi
	            ;;
		    ;;
	    esac
	    result="Using ${TCL_INCLUDES}"
	else
	    if test ! -f "${TCL_SRC_DIR}/generic/tclInt.h" ; then
		AC_MSG_ERROR([Cannot find private header tclInt.h in ${TCL_SRC_DIR}])
	    fi
	    result="Using srcdir found in tclConfig.sh: ${TCL_SRC_DIR}"