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This compliant solution ensures that the loop counter computation involves numbers less than 2<superscript>24</superscript>
(2⁴⁸ (that is, 281,474,976,710,656).

my $x = 10000000000000000;  # 1e+16
for (my $y = 0; $y <= 5; $y += 1) {
  my $z = $x + $y;
  print "$z\n";
}

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1e+16
1e+16
1e+16
1e+16
1e+16
1e+16

Compliant Solution

This compliant solution uses the Bignum module to ensure precise computation. The Bignum module is available in CPAN, but became part of Perl's standard library for version 5.8.

use bignum;
my $x = 10000000000000000;  # 1e+16
for (my $y = $x; $y <= $x + 5; $y += 1) {
  print "$y\n";
}

On a 32-bit machine, this program terminates normally after printing the following:

10000000000000000
10000000000000001
10000000000000002
10000000000000003
10000000000000004
10000000000000005

Risk Assessment

Failing to understand the limitations of floating-point numbers can result in unexpected computational results and exceptional conditions, possibly resulting in a violation of data integrity.

Bibliography

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