I get the same results as you for the second (although with warnings), but more drastic ones for the first! 
Name "main::a" used only once: possible typo at /tmp/t76 line 5.
Name "main::b" used only once: possible typo at /tmp/t76 line 5.
semi-panic: attempt to dup freed string at /tmp/t76 line 5.
Segmentation fault (core dumped)

This is with Perl 5.6.1, and List::Utils 1.11.

In reply to Re: An anomaly with List::Util::reduce and/or eval? by sgifford
in thread An anomaly with List::Util::reduce and/or eval? by BrowserUk

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