With a == &PL_sv_undef you are not testing if they contain the same value but if they are both pointers to the same scalar!

Doh!! ... thanks salva.

Cheers,
Rob

In reply to Re^5: testing for undef in perl XS code (in DBD::ODBC) by syphilis
in thread testing for undef in perl XS code (in DBD::ODBC) by mje

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