brix@fangorn ~ $ avr-gcc --version
avr-gcc (GCC) 3.4.5 (Gentoo 3.4.5, ssp-3.4.5-1.0, pie-8.7.9)
Copyright (C) 2004 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
brix@fangorn ~ $ avr-gcc --target-help
Target specific options:
-msize Output instruction sizes to the asm file
-mshort-calls Use rjmp/rcall (limited range) on >8K devices
-mno-tablejump Do not generate tablejump insns
-mtiny-stack Change only the low 8 bits of the stack pointer
-mcall-prologues Use subroutines for function prologue/epilogue
-mno-interrupts Change the stack pointer without disabling interrupts
-mint8 Assume int to be 8 bit integer
-mmcu= Specify the MCU name
-minit-stack= Specify the initial stack address
There are undocumented target specific options as well.
AVR options:
-mmcu=[avr-name] select microcontroller variant
[avr-name] can be:
avr1 - AT90S1200, ATtiny1x, ATtiny28
avr2 - AT90S2xxx, AT90S4xxx, AT90S8xxx, ATtiny22
avr3 - ATmega103, ATmega603
avr4 - ATmega83, ATmega85
avr5 - ATmega161, ATmega163, ATmega32, AT94K
or immediate microcontroller name.
-mall-opcodes accept all AVR opcodes, even if not supported by MCU
-mno-skip-bug disable warnings for skipping two-word instructions
(default for avr4, avr5)
-mno-wrap reject rjmp/rcall instructions with 8K wrap-around
(default for avr3, avr5)
Known MCU names:
avr1 avr2 avr3 avr4 avr5 at90s1200 attiny10 attiny11 attiny12 attiny15
attiny28 at90s2313 at90s2323 at90s2333 at90s2343 attiny22 attiny26
at90s4433 at90s4414 at90s4434 at90s8515 at90s8535 at90c8534 at86rf401
attiny13 attiny2313 attiny25 attiny45 attiny85 atmega603 atmega103
at43usb320 at43usb355 at76c711 atmega48 atmega8 atmega83 atmega85
atmega88 atmega8515 atmega8535 atmega16 atmega161 atmega162 atmega163
atmega164 atmega165 atmega168 atmega169 atmega32 atmega323 atmega324
atmega325 atmega329 atmega3250 atmega3290 atmega64 atmega644 atmega128
atmega645 atmega6450 atmega6490 at90can128 at94k
no emulation specific options.