else { /* long double */
union IEEEl2bits u;
u.e = nanl(cp);
-#if defined(__i386__) || defined(__x86_64__) || defined(__arm__)
+#if defined(__i386__) || defined(__x86_64__) || defined(__arm__) || defined(__arm64__)
x0[1] = (ULong)u.bits.manh;
x0[0] = (ULong)u.bits.manl;
#else