Greetings from a new member of your mailing list.

I have used Gnu Pascal for some time on a Windows 10 64-bit environment.

I decided to try it on a Linux Mint 20 Cinnamon machine with x86_64 processor
I downloaded gpc-2.1-with-gcc.i686-pc-linux-gnu.tar.gz to
 /home/peter/software and installed using:

cd /
tar xzf /home/peter/software/gpc-2.1-with-gcc.i686-pc-linux-gnu.tar.gz

I tried the simplest of programs: Hello.c:
program hello;
begin
    writeln ('Hello Pascal world');
    readln
end.
and compiled by gpc -o Hello    Hello.pas
to get, to my dismay, not as on Windows but on Linux:
peter@peter-Akoya-E6237:~/Pete/Pascal$ gpc -o Hello    Hello.pas
/tmp/ccnPqfBD.s: Assembler messages:
/tmp/ccnPqfBD.s:15: Error: invalid instruction suffix for `push'
/tmp/ccnPqfBD.s:19: Error: invalid instruction suffix for `push'
/tmp/ccnPqfBD.s:20: Error: invalid instruction suffix for `push'
/tmp/ccnPqfBD.s:21: Error: invalid instruction suffix for `push'
/tmp/ccnPqfBD.s:22: Error: invalid instruction suffix for `push'
/tmp/ccnPqfBD.s:23: Error: invalid instruction suffix for `push'
/tmp/ccnPqfBD.s:24: Error: invalid instruction suffix for `push'
/tmp/ccnPqfBD.s:25: Error: invalid instruction suffix for `push'
/tmp/ccnPqfBD.s:35: Error: invalid instruction suffix for `push'
/tmp/ccnPqfBD.s:36: Error: invalid instruction suffix for `push'
/tmp/ccnPqfBD.s:37: Error: invalid instruction suffix for `push'
/tmp/ccnPqfBD.s:38: Error: invalid instruction suffix for `push'
/tmp/ccnPqfBD.s:50: Error: invalid instruction suffix for `pop'
/tmp/ccnPqfBD.s:66: Error: invalid instruction suffix for `push'
/tmp/ccnPqfBD.s:73: Error: invalid instruction suffix for `push'
/tmp/ccnPqfBD.s:80: Error: invalid instruction suffix for `pop'
/tmp/ccnPqfBD.s:88: Error: invalid instruction suffix for `push'
/tmp/ccnPqfBD.s:92: Error: invalid instruction suffix for `pop'
/tmp/ccnPqfBD.s:103: Error: invalid instruction suffix for `push'
/tmp/ccnPqfBD.s:108: Error: invalid instruction suffix for `push'
/tmp/ccnPqfBD.s:110: Error: invalid instruction suffix for `push'
/tmp/ccnPqfBD.s:112: Error: invalid instruction suffix for `push'
/tmp/ccnPqfBD.s:123: Error: invalid instruction suffix for `pop'
peter@peter-Akoya-E6237:~/Pete/Pascal$

What am I doing wrong? Can you please advise?