warnings have lexical scope, so 

no warnings;

sub test_warnings {
    GenerateWarning();
    AnotherSub();
}

sub AnotherSub {
    GenerateWarning();
}

[download]

also, may be this code be useful for you 

sub test_warnings {
    local $SIG{__WARN__} = sub {};
    GenerateWarning();
    AnotherSub();
}

[download]

In reply to Re: Nested runtime warning disabling by ccn
in thread Nested runtime warning disabling by kryten

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