How to slice array of awk-output in bash?

Question

Summary

Depending on what bash or awk version I have, I get different results when I try to slice an array that holds awk output. On older versions of bash and awk the "slice operation" ( e.g. ${a[@]:2}) incorrectly returns an array with a single element regardless of how many elements are left in the sliced array. However, this only seems to be an issue when slicing arrays that "capture" awk output.

MWE

• You can run the following to reproduce the issue:

    bash array_slice.sh text.file
  

  where array_slice.sh and text.file are the following:

• array_slice.sh script:

     #!/usr/bin/env bash                                                        
  
     defaultIFS=$IFS                                                            
     IFS=$'\n'                                                                  
     t=($(awk '{ printf("%s\n", $0) }' "$1"))                                   
     printf "\nArray 't' has ${#t[@]} elements\n"                               
     printf "Elements of array 't':\n"                                          
     printf "%s\n" "${t[@]}"                                                    
  
     t45=( ${t[@]:4} )                                                          
     printf "\nArray 't45' has ${#t45[@]} elements\n"                           
     printf "Elements of array 't45':\n"                                        
     printf "%s\n" "${t45[@]}"      
  

• text.file :

    some text                                                                   
    some other text                                                             
    this is text too                                                            
    text above is text                                                          
    and text below is text text                                                 
    text text  
  

Output for various platforms

Notice how array t45 only has one element in Ubuntu 16.04's output (it's supposed to have two) and how it correctly has two elements in Ubuntu 20.04's output.

• Ubuntu 16.04 with

  • GNU Awk 4.1.3, API: 1.1 (GNU MPFR 3.1.4, GNU MP 6.1.0)
  • GNU bash, version 4.3.48(1)-release (x86_64-pc-linux-gnu) Gives:

    Array 't' has 6 elements
    Elements of array 't':
    some text
    some other text
    this is text too
    text above is text
    and text below is text text
    text text
  
    Array 't45' has 1 elements
    Elements of array 't45':
    and text below is text text text text
  

• Ubuntu 20.04 with

  • GNU Awk 5.0.1, API: 2.0 (GNU MPFR 4.0.2, GNU MP 6.2.0)
  • GNU bash, version 5.0.17(1)-release (x86_64-pc-linux-gnu) Gives:

  Array 't' has 6 elements
  Elements of array 't':
  some text
  some other text
  this is text too
  text above is text
  and text below is text text
  text text
  
  Array 't45' has 2 elements
  Elements of array 't45':
  and text below is text text
  text text