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Error: Junk at end of line -as and -o error with ARM

I am attempting to write my first ARM program and getting this error when I try to run "as -o labl1.o lab1.s"

lab1.s:3: Error: junk at end of line, first unrecognized character is `s'

I am very unsure about what I am doing wrong here, as the only times I use s is in my 2 strings, and very puzzled on where in the code I went wrong.


@Data
.data
string1: .asciz
string2: .asciz

@Code
.text
.global main
.extern printf

main:

push {ip, lr}

push {r0, r1, r2}
ldr r0, =string1
mov r1, #34
mov r2, #56
bl printf
pop {r0,r1,r2}

push {r0}
ldr r0, =string2
bl printf
pop {r0}

pop {ip, pc}

Links to helpful documents or help debugging would be greatly appreciated, thank you!

Solution

  • You may be confusing the address of your strings and the values you want to assign them: As specified in GNU as documentation, the .asciz directive does require a string argument - a slightly modified version of your code does assemble correctly:

    .data
string1: .asciz "string1"
string2: .asciz "string2"

    string1 is now the label for the address where bytes "string1\x00" are located, and string2 is the label for the address where bytes "string2\x00" are.