As I understand, the two exit procedures only matter if you fork.

This is on windows, clean exit

perl -e"use Tk; $mw=tkinit; $mw->Button(-command=>sub{ Tk::exit })->pa
+ck; MainLoop; "
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Dirty exit

perl -e"use Tk; $mw=tkinit; $mw->Button(-command=>sub{ CORE::exit })->
+pack; MainLoop; "

perl.exe has encountered a problem and needs to close.

Faulting application perl.exe, version 5.20.3.3, faulting module tk.xs
+.dll, version 8.4.2.5, fault address 0x00044b1e.
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