It ought to be possible to make a single determination at the top of a routine

That is how it's done. A single SvGETMAGIC if you read a scalar, no matter how many times you read it. A single SvSETMAGIC if you write to a scalar, no matter how many times you write to it. You don't want to call magic twice, and not just for performance reasons.

In reply to Re^5: XS: returning a 64-bit unsigned int? by ikegami
in thread XS: returning a 64-bit unsigned int? by BrowserUk

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