diff -Naurp gcc/config/avr/avr-devices.c gcc/config/avr/avr-devices.c
--- gcc/config/avr/avr-devices.c	2011-10-28 11:55:44.000000000 +0530
+++ gcc/config/avr/avr-devices.c	2011-10-28 12:00:41.000000000 +0530
@@ -295,6 +295,7 @@ const struct mcu_type_s avr_mcu_types[] 
   { "avrxmega7",    ARCH_AVRXMEGA7, NULL,                           0, 0x2000, "x128a1" },
   { "atxmega128a1", ARCH_AVRXMEGA7, "__AVR_ATxmega128A1__",         0, 0x2000, "x128a1" },
   { "atxmega128a1u", ARCH_AVRXMEGA7, "__AVR_ATxmega128A1U__",       0, 0x2000, "x128a1u" },
+  { "atxmega128a4u", ARCH_AVRXMEGA7, "__AVR_ATxmega128A4U__",       0, 0x2000, "x128a4u" },
  	/* tiny10 family */
   { "avrtiny10",   ARCH_AVRTINY10, NULL,                            0, 0x0040, "tn10" },
   { "attiny4",     ARCH_AVRTINY10, "__AVR_ATtiny4__",               0, 0x0040, "tn4" },
diff -Naurp gcc/config/avr/t-avr gcc/config/avr/t-avr
--- gcc/config/avr/t-avr	2011-10-28 11:55:44.000000000 +0530
+++ gcc/config/avr/t-avr	2011-10-28 12:00:41.000000000 +0530
@@ -299,6 +299,7 @@ MULTILIB_MATCHES = \
 	mmcu?avrxmega6=mmcu?atxmega384c3 \
 	mmcu?avrxmega7=mmcu?atxmega128a1 \
 	mmcu?avrxmega7=mmcu?atxmega128a1u \
+	mmcu?avrxmega7=mmcu?atxmega128a4u \
 	mmcu?avrtiny10=mmcu?attiny4 \
 	mmcu?avrtiny10=mmcu?attiny5 \
 	mmcu?avrtiny10=mmcu?attiny9 \