+# Check whether --enable-packihx or --disable-packihx was given.
+if test "${enable_packihx+set}" = set; then
+ enableval="$enable_packihx"
+ :
+fi
+
+OPT_ENABLE_PACKIHX=$enable_packihx
+
+
+# Check whether --enable-libgc or --disable-libgc was given.
+if test "${enable_libgc+set}" = set; then
+ enableval="$enable_libgc"
+ :
+fi
+
+if test "$enable_libgc" = "yes"; then
+ echo $ac_n "checking for GC_malloc in -lgc""... $ac_c" 1>&6
+echo "configure:2826: checking for GC_malloc in -lgc" >&5
+ac_lib_var=`echo gc'_'GC_malloc | sed 'y%./+-%__p_%'`
+if eval "test \"`echo '$''{'ac_cv_lib_$ac_lib_var'+set}'`\" = set"; then
+ echo $ac_n "(cached) $ac_c" 1>&6
+else
+ ac_save_LIBS="$LIBS"
+LIBS="-lgc $LIBS"
+cat > conftest.$ac_ext <<EOF
+#line 2834 "configure"
+#include "confdefs.h"
+/* Override any gcc2 internal prototype to avoid an error. */
+/* We use char because int might match the return type of a gcc2
+ builtin and then its argument prototype would still apply. */
+char GC_malloc();
+
+int main() {
+GC_malloc()
+; return 0; }
+EOF
+if { (eval echo configure:2845: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+ rm -rf conftest*
+ eval "ac_cv_lib_$ac_lib_var=yes"
+else
+ echo "configure: failed program was:" >&5
+ cat conftest.$ac_ext >&5
+ rm -rf conftest*
+ eval "ac_cv_lib_$ac_lib_var=no"
+fi
+rm -f conftest*
+LIBS="$ac_save_LIBS"
+
+fi
+if eval "test \"`echo '$ac_cv_lib_'$ac_lib_var`\" = yes"; then
+ echo "$ac_t""yes" 1>&6
+ ac_tr_lib=HAVE_LIB`echo gc | sed -e 's/[^a-zA-Z0-9_]/_/g' \
+ -e 'y/abcdefghijklmnopqrstuvwxyz/ABCDEFGHIJKLMNOPQRSTUVWXYZ/'`
+ cat >> confdefs.h <<EOF
+#define $ac_tr_lib 1
+EOF
+
+ LIBS="-lgc $LIBS"
+
+else
+ echo "$ac_t""no" 1>&6
+fi
+
+ OPT_ENABLE_LIBGC=1
+else
+ OPT_ENABLE_LIBGC=0
+fi
+cat >> confdefs.h <<EOF
+#define OPT_ENABLE_LIBGC $OPT_ENABLE_LIBGC
+EOF
+
+