diff --git a/configure.ac b/configure.ac

index 26c509e..c1bfd62 100644

--- a/configure.ac

+++ b/configure.ac

@@ -4152,6 +4152,10 @@ if test "yes" = "$use_atomic"; then

 	AC_MSG_RESULT($arch)

 fi

+if test ! "$arch" = "x86_64" -a "$have_xaddq" = "yes"; then

+	AC_MSG_ERROR([XADDQ present but disabled by Fedora patch!])

+fi

+

 if test "yes" = "$have_atomic"; then

 	AC_MSG_CHECKING([compiler support for inline assembly code])

diff --git a/lib/isc/include/isc/platform.h.in b/lib/isc/include/isc/platform.h.in

index c902d46..9c7c342 100644

--- a/lib/isc/include/isc/platform.h.in

+++ b/lib/isc/include/isc/platform.h.in

@@ -284,19 +284,25 @@

  * If the "xaddq" operation (64bit xadd) is available on this architecture,

  * ISC_PLATFORM_HAVEXADDQ will be defined.

  */

-@ISC_PLATFORM_HAVEXADDQ@

 /*

- * If the 32-bit "atomic swap" operation is available on this

- * architecture, ISC_PLATFORM_HAVEATOMICSTORE" will be defined.

+ * If the 64-bit "atomic swap" operation is available on this

+ * architecture, ISC_PLATFORM_HAVEATOMICSTOREQ" will be defined.

  */

-@ISC_PLATFORM_HAVEATOMICSTORE@

+

+#ifdef __x86_64__

+#define ISC_PLATFORM_HAVEXADDQ 1

+#define ISC_PLATFORM_HAVEATOMICSTOREQ 1

+#else

+#undef ISC_PLATFORM_HAVEXADDQ

+#undef ISC_PLATFORM_HAVEATOMICSTOREQ

+#endif

 /*

- * If the 64-bit "atomic swap" operation is available on this

+ * If the 32-bit "atomic swap" operation is available on this

  * architecture, ISC_PLATFORM_HAVEATOMICSTORE" will be defined.

  */

-@ISC_PLATFORM_HAVEATOMICSTOREQ@

+@ISC_PLATFORM_HAVEATOMICSTORE@

 /*

  * If the "compare-and-exchange" operation is available on this architecture,