Like Burak and like I already said, I can't replicate your behaviour.

However, it is possible for $@ to get cleared. For example, if you have an object that gets destroyed in the eval and it uses eval in its destructor, $@ would get cleared. That's why you shouldn't rely on $@ being set to detect an exception. 

my $result;
if (!eval {
   ...
   $result = ...;
   1;
}) {
   die("Unable to ...: $@\n");
}

[download]

That said, I'd like to present a better solution to your initial problem. I propose there's a bug in your global __DIE__ handler. It should check $^S just rethrow the exception if it's true. 

local $SIG{'__DIE__'} = sub {
   die($@) if $^S;
   ...
};

[download]

In reply to Re: 5.10 shows uninitialized $@ warning by ikegami
in thread 5.10 shows uninitialized $@ warning by pmSwim

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