Must be buitin

ext/spl/config.m4

@@ -5,6 +5,9 @@ PHP_ARG_ENABLE(spl, enable SPL suppport,
 [  --disable-spl           Enable Standard PHP Library], yes)
 
 if test "$PHP_SPL" != "no"; then
+	if test "$ext_shared" = "yes"; then
+		AC_MSG_ERROR(Cannot build SPL as a shared module)
+	fi
     AC_DEFINE(HAVE_SPL, 1, [Whether you want SPL (Standard PHP Library) support]) 
     PHP_NEW_EXTENSION(spl, php_spl.c spl_functions.c spl_engine.c spl_iterators.c spl_array.c spl_directory.c spl_sxe.c, $ext_shared)
 fi