Does it help if you change your code to not pass a reference to undef, but instead just pass undef?

   my $bar = Foo::create_bar($foo);

That seems like a more straight-forward representation of C's NULL to me.

-sam

In reply to Re: Passing NULL pointer through XS without "Use of uninitialized value in subroutine entry" by samtregar
in thread Passing NULL pointer through XS without "Use of uninitialized value in subroutine entry" by kscaldef

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