You might additionally want to check whether Util.so is in fact being loaded: 

$ strace -efile perl -MScalar::Util=weaken -e'weaken(\my $var)' 2>&1 |
+ grep Util\.so

[download]

With a working installation, the results should look something like 

stat("/usr/lib/perl5/5.8.8/auto/List/Util/Util.so", 0x63b140) = -1 ENO
+ENT (No such file or directory)
stat("/usr/lib/perl5/5.8.8/x86_64-linux-thread-multi/auto/List/Util/Ut
+il.so", {st_mode=S_IFREG|0555, st_size=40616, ...}) = 0
open("/usr/lib/perl5/5.8.8/x86_64-linux-thread-multi/auto/List/Util/Ut
+il.so", O_RDONLY) = 6

[download]

Otherwise, you'd get stat()s with ENOENT only (several dozens, typically), or maybe an attempted open() with EACCES (Permission denied), but no successful open()

In reply to Re^3: CPAN and "Weak references" by almut
in thread CPAN and "Weak references" by arthurg

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