The fix has no effect on: 

my $ref;
{
    my $string = "123";
    $ref = \substr $string, 1, 1;
}

## This was the (IMO false) "bug" scenario.

[download]

The fix is for: 

{
    my $string = "123";
    my $ref = \substr $string, 1, 1;
}

[download]

All the patch does (or is suppose to do) is avoid saving the SV inside of the OP, something that causes $string until the end of the program in the second snippet.

Do you have a way of automating the test so I can use git bisect to find when the behaviour changed (if it did).

In reply to Re^7: Tracking down an Lvalue bug? by ikegami
in thread Tracking down an Lvalue bug? by BrowserUk

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