-Wl,-export-dynamic tells the linker we want an entry point of 'xport-dynamic'.
Fix the typo accordingly.

https://sourceforge.net/p/xsb/bugs/266/
--- a/build/configure.in
+++ b/build/configure.in
@@ -1343,10 +1343,10 @@ else
 fi
 
 
-####### Test for -export-dynamic option of ld
+####### Test for --export-dynamic option of ld
 TEMP_LDFLAGS=$LDFLAGS
-LDFLAGS="-Wl,-export-dynamic"
-AC_MSG_CHECKING([whether loader understands -Wl,-export-dynamic])
+LDFLAGS="-Wl,--export-dynamic"
+AC_MSG_CHECKING([whether loader understands -Wl,--export-dynamic])
 # Ideally we should use AC_LINK_IFELSE instead of the obsolete AC_TRY_LINK
 #AC_TRY_LINK([],[], __export_dynamic=yes, __export_dynamic=no)
 AC_LINK_IFELSE([AC_LANG_SOURCE([[int main(){return 0;}]])], __export_dynamic=yes, __export_dynamic=no)
@@ -1402,7 +1402,7 @@ case "$canonical" in
                             LDFLAGS="${LDFLAGS} -ldl"
 
                             if test "$__export_dynamic" = "yes" ; then
-                                LDFLAGS="${LDFLAGS} -Wl,-export-dynamic"
+                                LDFLAGS="${LDFLAGS} -Wl,--export-dynamic"
                             fi
                         fi
 
@@ -1416,7 +1416,7 @@ case "$canonical" in
     *freebsd* ) AC_DEFINE(FREEBSD)
                 AC_DEFINE(FOREIGN_ELF)
                 if test "$__export_dynamic" = "yes" ; then
-                    LDFLAGS="${LDFLAGS} -Wl,-export-dynamic"
+                    LDFLAGS="${LDFLAGS} -Wl,--export-dynamic"
                 fi
 
                 if test "${have_dl}" = yes ; then
@@ -1498,7 +1498,7 @@ case "$canonical" in
 
                 LDFLAGS="-lsocket ${LDFLAGS}"
                 if test "$__export_dynamic" = "yes" ; then
-                    LDFLAGS="${LDFLAGS} -Wl,-export-dynamic"
+                    LDFLAGS="${LDFLAGS} -Wl,--export-dynamic"
                 fi
                 if test "${have_socket}" = "no" ; then
                     AC_MSG_ERROR(Your system is missing library: \`socket')