Failure with libidn2 on OpenBSD.

[Mats Erik Andersson]

Hello there,

since Simon Josefsson and Tim Rühsen are both involved in libidn2,
this bug is doubly relevant here.

The following call

   host = "::1";

   idna_to_ascii_lz(host, &newhost, 0);

results in

   newhost = "1"

when executed on OpenBSD 6.3 with libidn2. This is clearly not intended. Right?
In contrast, FreeBSD 11 with libidn and OpenIndiana with libidn2, both lead to

   newhost = "::1"

which is to be expected of an IPv6 address. Similarly, the OpenBSD+libidn2
call transforms the legal "::ffff:127.0.0.1" for the corrupted "ffff127.0.0.1".

Thus the compatibility call idna_to_ascii_lz() in libidn2 strips off every 
colon,
when executed on OpenBSD but not on OpenIndiana. Explanation? Resolution?
I get two failed tests with OpenBSD, but none with OpenIndiana!

Regards
  M E Andersson