Use Config and check the ivsize key:

C:\test>perl -MConfig -E"say $Config{ ivsize }"
8

C:\test>\perl32\bin\perl -MConfig -le"print $Config{ ivsize }"
4

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In reply to Re: reliably test integer size for portable bit-fiddling? by BrowserUk
in thread reliably test integer size for portable bit-fiddling? by wollmers

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