[perl #118455] "no warnings 'exec'" does not disable "Statement unlikely to be reached"

I have pushed 3cf2ee4e44b339198562fa5f52af6a52e85d52a8 as smoke-me/rjbs/exec-
warning.

Please give it a look, anybody, and comment before I merge in a day or three.

-- 
rjbs

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via perlbug:  queue: perl5 status: new
https://rt.perl.org:443/rt3/Ticket/Display.html?id=118455

• [perl #118455] "no warnings 'exec'" does not disable "Statement unlikely to be reached" by Ricardo SIGNES via RT
• [perl #118455] "no warnings 'exec'" does not disable "Statement unlikely to be reached" by Father Chrysostomos via RT
• Re: [perl #118455] "no warnings 'exec'" does not disable "Statementunlikely to be reached" by Ricardo Signes