I am working on a XS module (Foo), that at some point has to convert an SV returned from a Perl callback to a double and does so with SvNV(). If the callback returns something that is not a number, a warning is printed but it points to the line on my module calling the xsub: 
Argument "foo" isn't numeric in subroutine entry at /usr/local/lib/per
+l/5.8.4/Foo.pm line 84.

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I would like it to point not to my module but to the calling one as Carp::carp would do, and to not print anything unless use warnings had been used on the calling module.

A possible solution for that would be to precheck the SV with looks_like_number() and add some logic to act accordingly, but this seems inelegant to me, so is there any other way of doing it?

In reply to warnings from API calls on XS by salva

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