Question

I can’t tell if this is a bug or what.

The following code works with Inline::C but not Inline::CPP

#!/usr/bin/perl
use warnings;
use Inline C;

my @array = (1..10);
print findAvLen(\@array), "\n";

__END__
__C__

int findAvLen(AV* arrayIn) {
    return av_len(arrayIn);
}

The above runs fine, but replace C with CPP, and I get the error Can't locate auto/main/findAvLen.al in @INC...

I can get other inline c++ code to work. It is possible, for instance, to pass a list of variables to inline code with an ellipsis as they do in this example, but I wonder why AV* isn’t working! For instance, I will want to use a subroutine to converts perl arrays passed to C++ into vectors, e.g. void perl2vector(AV* ar, std::vector<T> &v) {...}, rather than inserting code to perform such conversion into every C++ function I write that takes an array argument. How could I use that example’s syntax to pass the perl array to such a converter?

---

This does seem to be a bug, but in the meantime, uesp has found a workaround:

int findAvLen(SV* arrRef) { 
    AV * arr = MUTABLE_AV(SvRV(arrRef));
    return av_len(arr);
}

arr is now equivalent to the arrayIn desired in the example code above.

Answer 1

This appears to be be identical to this Perl bug which exists in 5.10.0 and should have been fixed in release 5.10.29. If you are running 5.10.0-28 try updating. If you aren’t running these versions and still getting the error you can try doing what is mentioned in this forum post by changing the AV to SV.