diff -Naurp gcc/config/avr/avr-devices.c gcc/config/avr/avr-devices.c
--- gcc/config/avr/avr-devices.c	2011-10-28 14:59:12.000000000 +0530
+++ gcc/config/avr/avr-devices.c	2011-10-28 15:04:23.000000000 +0530
@@ -294,6 +294,7 @@ const struct mcu_type_s avr_mcu_types[] 
   { "atxmega128b1", ARCH_AVRXMEGA6, "__AVR_ATxmega128B1__",         0, 0x2000, "x128b1" },
   { "atxmega128b3", ARCH_AVRXMEGA6, "__AVR_ATxmega128B3__",         0, 0x2000, "x128b3" },
   { "atxmega128d3", ARCH_AVRXMEGA6, "__AVR_ATxmega128D3__",         0, 0x2000, "x128d3" },
+  { "atxmega128d4", ARCH_AVRXMEGA6, "__AVR_ATxmega128D4__",         0, 0x2000, "x128d4" },
   { "atxmega192a3", ARCH_AVRXMEGA6, "__AVR_ATxmega192A3__",         0, 0x2000, "x192a3" },
   { "atxmega192a3u",ARCH_AVRXMEGA6, "__AVR_ATxmega192A3U__",        0, 0x2000, "x192a3u"},
   { "atxmega192d3", ARCH_AVRXMEGA6, "__AVR_ATxmega192D3__",         0, 0x2000, "x192d3" },
diff -Naurp gcc/config/avr/t-avr gcc/config/avr/t-avr
--- gcc/config/avr/t-avr	2011-10-28 14:59:12.000000000 +0530
+++ gcc/config/avr/t-avr	2011-10-28 15:04:23.000000000 +0530
@@ -300,6 +300,7 @@ MULTILIB_MATCHES = \
 	mmcu?avrxmega6=mmcu?atxmega128b1 \
 	mmcu?avrxmega6=mmcu?atxmega128b3 \
 	mmcu?avrxmega6=mmcu?atxmega128d3 \
+	mmcu?avrxmega6=mmcu?atxmega128d4 \
 	mmcu?avrxmega6=mmcu?atxmega192a3 \
 	mmcu?avrxmega6=mmcu?atxmega192a3u \
 	mmcu?avrxmega6=mmcu?atxmega192d3 \