title: Assembly error when compiling with GCC
body: <p>I'm getting "no such instruction" errors when compiling a .s file with this command: </p>
  
  <pre><code>$ gcc -s -o scall scall.s
  scall.s: Assembler messages:
  scall.s:2: Error: no such instruction: `section '
  scall.s:4: Error: no such instruction: `global _start'
  scall.s:7: Error: unsupported instruction `mov'
  scall.s:8: Error: unsupported instruction `mov'
  scall.s:11: Error: operand size mismatch for `int'
  scall.s:13: Error: no such instruction: `section .data'
  scall.s:15: Error: no such instruction: `msglength .word 12'
  </code></pre>
  
  <p>Here is the code of the file:</p>
  
  <pre><code>section .text
      global _start
  
  _start:
      mov 4,%eax
      mov 1,%ebx
      mov $message,%ecx
      mov $msglength,%edx
      int  $0x80
  
  section .data
     message: .ascii "Hello world!"
     msglength .word 12
  </code></pre>
  
  <p>How can I get rid of the errors?</p>