Do you have to use just one regexp? The following will work in Java, and is only compiled once:

my @regexps = (
  qr/a/,
  qr/ab/,
  qr/abc/,
);

my $text = 'aababc';

my @matches;

foreach ($text) {  # Safe $_ = $text;
   foreach my $re (@regexps) {
      push(@matches, /($re)/g);
   }
}

print("$_\n")
   foreach @matches;
[download]

a     (at pos 0)
a     (at pos 1)
a     (at pos 3)
ab    (at pos 0)
ab    (at pos 3)
abc   (at pos 3)
[download]

Remove the "g" from "/($re)/g" to match each regexp only once.