diff --git a/config.m4 b/config.m4
index 59b91d2..b76b997 100644
--- a/config.m4
+++ b/config.m4
@@ -7,7 +7,10 @@ AC_DEFUN([XCACHE_OPTION], [
   [  --enable-xcache-$2    XCACHE: $4], no, no)
   if test "$PHP_$3" = "yes"; then
     xcache_sources="$xcache_sources $1.c"
+    HAVE_$3=1
     AC_DEFINE([HAVE_$3], 1, [Define for XCACHE: $4])
+  else
+    HAVE_$3=
   fi
 ])dnl
 
@@ -56,6 +59,23 @@ if test "$PHP_XCACHE" != "no"; then
   esac
   PHP_SUBST([XCACHE_INDENT])
 
+  dnl $ac_srcdir etc require PHP_NEW_EXTENSION
   XCACHE_PROC_SOURCES=`ls $ac_srcdir/processor/*.m4`
   PHP_SUBST([XCACHE_PROC_SOURCES])
+
+  AC_MSG_CHECKING(if you have opcode_spec_def.h for xcache)
+  if test -e "$ac_srcdir/opcode_spec_def.h" ; then
+    AC_DEFINE([HAVE_XCACHE_OPCODE_SPEC_DEF], 1, [Define if you have opcode_spec_def.h for xcache])
+    AC_MSG_RESULT(yes)
+  else
+    dnl check for features depend on opcode_spec_def.h
+    AC_MSG_RESULT(no)
+    define([ERROR], [
+      AC_MSG_ERROR([cannot build with $1, $ac_srcdir/opcode_spec_def.h required])
+    ])
+    if test "$HAVE_XCACHE_DISASSEMBLER" = "1" ; then
+      ERROR(disassembler)
+    fi
+    undefine([ERROR])
+  fi
 fi
diff --git a/disassembler.c b/disassembler.c
index 17cfc2d..832f30e 100644
--- a/disassembler.c
+++ b/disassembler.c
@@ -5,6 +5,9 @@
 
 #define return_value dst
 
+#ifndef HAVE_XCACHE_OPCODE_SPEC_DEF
+#error disassembler cannot be built without xcache/opcode_spec_def.h
+#endif
 static void xc_dasm(zval *dst, zend_op_array *op_array TSRMLS_DC) /* {{{ */
 {
 	Bucket *b;
diff --git a/opcode_spec.c b/opcode_spec.c
index d0af327..02be534 100644
--- a/opcode_spec.c
+++ b/opcode_spec.c
@@ -2,6 +2,7 @@
 #include "opcode_spec.h"
 #include "const_string.h"
 
+#ifdef HAVE_XCACHE_OPCODE_SPEC_DEF
 /* {{{ opcode_spec */
 #define OPSPEC(ext, op1, op2, res) { OPSPEC_##ext, OPSPEC_##op1, OPSPEC_##op2, OPSPEC_##res },
 #ifdef ZEND_ENGINE_2
@@ -23,6 +24,7 @@ const xc_opcode_spec_t *xc_get_opcode_spec(zend_uchar opcode)
 	return &xc_opcode_spec[opcode];
 }
 /* }}} */
+#endif
 /* {{{ op_spec */
 
 #define OPSPECS_DEF_NAME(name) #name,
diff --git a/utils.c b/utils.c
index c306aec..1bb8210 100644
--- a/utils.c
+++ b/utils.c
@@ -197,6 +197,7 @@ int xc_redo_pass_two(zend_op_array *op_array TSRMLS_DC) /* {{{ */
 }
 /* }}} */
 
+#ifdef HAVE_XCACHE_OPCODE_SPEC_DEF
 static void xc_fix_opcode_ex_znode(int tofix, xc_op_spec_t spec, znode *znode, int type TSRMLS_DC) /* {{{ */
 {
 #ifdef ZEND_ENGINE_2
@@ -261,6 +262,7 @@ int xc_undo_fix_opcode(zend_op_array *op_array TSRMLS_DC) /* {{{ */
 	return 0;
 }
 /* }}} */
+#endif
 
 void xc_install_function(char *filename, zend_function *func, zend_uchar type, char *key, uint len TSRMLS_DC) /* {{{ */
 {
diff --git a/xcache.c b/xcache.c
index b8d41b7..8a6a3f2 100644
--- a/xcache.c
+++ b/xcache.c
@@ -1505,6 +1505,7 @@ PHP_FUNCTION(xcache_get_op_spec)
 	xc_call_getter(xc_get_op_spec, xc_get_op_spec_count(), INTERNAL_FUNCTION_PARAM_PASSTHRU);
 }
 /* }}} */
+#ifdef HAVE_XCACHE_OPCODE_SPEC_DEF
 /* {{{ proto string xcache_get_opcode_spec(int opcode) */
 PHP_FUNCTION(xcache_get_opcode_spec)
 {
@@ -1528,6 +1529,7 @@ PHP_FUNCTION(xcache_get_opcode_spec)
 	RETURN_NULL();
 }
 /* }}} */
+#endif
 /* {{{ proto mixed xcache_get_special_value(zval value) */
 PHP_FUNCTION(xcache_get_special_value)
 {
@@ -1600,7 +1602,9 @@ static function_entry xcache_functions[] = /* {{{ */
 	PHP_FE(xcache_get_op_type,       NULL)
 	PHP_FE(xcache_get_data_type,     NULL)
 	PHP_FE(xcache_get_opcode,        NULL)
+#ifdef HAVE_XCACHE_OPCODE_SPEC_DEF
 	PHP_FE(xcache_get_opcode_spec,   NULL)
+#endif
 	PHP_FE(xcache_is_autoglobal,     NULL)
 	PHP_FE(xcache_inc,               NULL)
 	PHP_FE(xcache_dec,               NULL)