local *CORE::GLOBAL::die = sub (@) {
    die scalar(localtime()), ' ', @_;
};

##</code><code>##

$ perl -e'local *CORE::GLOBAL::die = sub (@) {CORE::die(scalar(localtime()), " ", @_);}; die "Foo!"'
Foo! at -e line 1.
$ 

##</code><code>##

$ perl -e'print prototype "CORE::die"'
@$ 

##</code><code>##

BEGIN {
    *CORE::GLOBAL::warn = sub (@) {
        CORE::warn(scalar(localtime), " ", @_);
    };
    warn "Foo!";
}
BEGIN {
    *CORE::GLOBAL::warn = sub (@) {
        CORE::warn( @_);
    };
}
warn "Bar!"'
__END__
Foo! at -e line 1.
Bar! at -e line 1.