Those criteria for when untainting is done and when not look random to me.

Could it be as simple as whether the regex engine is used internally, during the parsing of the unpack template?

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In reply to Re^2: pack() untaints data : bug or undocumented Perl 5.10 feature? by BrowserUk
in thread pack() untaints data : bug or undocumented Perl 5.10 feature? by mr_mischief

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