I've come to the conclusion that you've hit an unfortunate case - the EXTEND macro evaluates its arguments several times

It sounds like you're saying that's the problem, but it took a a few reads to realize this isn't actually a problem here. The actual problem is the fact that the macro and the caller both use a var named ix.

NERDVANA said,

A good reminder to not use expressions inside macros.

The relevant lesson is to not use variable names in macros that could possibly be used outside the macro.

In reply to Re^2: XS debugging "failed to extend arg stack" by ikegami
in thread [Solved] XS debugging "failed to extend arg stack" by NERDVANA

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