You can use eval with FATAL warnings: 
#!/usr/bin/perl
use strict;
use warnings;

use open OUT => ':encoding(UTF-8)', ':std';
use warnings FATAL => 'utf8';

my $text = { string => "t\x{daed}\x{ffff}\x{daee}\x{c8}\n" };

1 until eval {
    print $text->{string};
    1;

} or do {
    my ($charcode) = $@ =~ /U\+(\S+)/ or die $@;
    print STDERR "Removing $charcode because of $@";
    $text->{string} =~ s/\x{$charcode}//g;
    0; # Try again!
};

[download]

Update: handles both "non-character" and "surrogate" cases. I wasn't able to trigger the "non_unicode" warnings.

لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ

In reply to Re: Unicode surrogate is illegal in UTF-8 by choroba
in thread Unicode surrogate is illegal in UTF-8 by Rodster001

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