in reply to Re^3: CPAN and "Weak references"
in thread CPAN and "Weak references"

But List::Util (to which List/Util/Util.so belongs) is a different module than Scalar::Util.

List/Util/Util.so does in fact belong to Scalar::Util (the module is somewhat peculiar in that respect). 

$ nm -D /usr/lib/perl5/5.8.8/x86_64-linux-thread-multi/auto/List/Util/
+Util.so | grep weaken
                 U Perl_sv_rvweaken
0000000000003f70 T XS_Scalar__Util_weaken

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