What's even weirder is that warn ref $f returns Math::BigInt , but constructors of Math::BigInt and Math::BigFloat are still seen as different:

warn $_->can('new') for qw( Math::BigInt Math::BigFloat );
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($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,
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