'How do you enter command line arguments in SPIM

I am trying to make programs using argc and argv in MIPS simulator SPIM. This is my code:

.data
nl: .asciiz "\n"

.globl main
.text
main:
  # print argv[0]
  lw $a0, 0($a1)
  li $v0, 4
  syscall
  # print "\n"
  li $v0, 4
  la $a0, nl
  syscall
  # exit
  li $v0, 10
  syscall

When I run

$ spim -f args.s
Loaded: /usr/share/spim/exceptions.s                                                                    
args.s

I get the correct result argv[0] (the name of the program). But if I try

$ spim -f args.s hello
Loaded: /usr/share/spim/exceptions.s
Cannot open file: `(null)'
Memory address out of bounds

I get that error. I searched everywhere but couldn't find anything. What's the correct way to pass arguments to argv[]? Changing the lw in the code to lw $a0, 4($a1) gets me the following output.

$ spim -f args.s hello
Loaded: /usr/share/spim/exceptions.s
Cannot open file: `(null)'
SHELL=/bin/zsh

I tried in the virtual console and it's the same. After printing all the environment variables changing the offset in the lw it justs prints "Memory address out of bounds".

I don't know what I am doing wrong.

assemblycommand-linemipsspim


Solution 1:[1]

Finally solved it. The right way to use program arguments is indeed

$ spim -f code.s arg1 arg2 etc

Turns out I was wrong when I said that I installed it from the AUR, I compiled it from source using the last snapshot on the official Sourceforge repo. There is a bug in spim.cpp. After line 278 it should say break; and it works flawlessly. I already created a ticket in Sourceforge so they can patch it.

Sources

This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.

Source: Stack Overflow

Solution Source
Solution 1 Santiago Trini

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