avr-ld rjmp 2-off anomaly

[Karakó Tibor]

Hi,

I ran into a weird situation regarding whether I compile and link the 
code in one go or in two phases.

main.c:

int main() {
    asm("out 0x14, r24");
        while (1) {
        asm("out 0x16, r24");
    }
}

When I run:

avr-gcc -O main.c -o main_one.hex -mmcu=attiny2313 -Wl,--oformat,ihex

I get a different result compared to:

avr-gcc -O main.c -o main_two.elf -mmcu=attiny2313
avr-ld -o main_two.elf.hex --oformat ihex main_two.elf

$ avr-objdump -j .sec1 -d -m avr main_two.elf.hex

 38:   fe cf           rjmp    .-4             ;  0x36

It calculates the jump correctly.

But the former one seems to introduce a 2-off bug when calculating the 
rjmps' offset:

$ avr-objdump -j .sec1 -d -m avr main_one.hex

  38:   ff cf           rjmp    .-2             ;  0x38

The same goes for every rjmp.

Is this a legit bug, or I am missing something?


gcc-avr(1:5.4.0+Atmel3.6.2-1)

binutils-avr(2.26.20160125+Atmel3.6.2-2)


Br,

Tibor