libcryptui needs to enable use of gnupg 2.1. This seems to be validated. See e.g. (ChangeLog): http://rpmfind.net/linux/RPM/opensuse/factory/aarch64/noarch/libcryptui-lang-3.12.2-4.1.noarch.html Reproducible: Always
Created attachment 404990 [details, diff] Enable gnupg 2.1 in libcryptui ebuild
AFAIK, 2.1 support in all parts of the seahorse / gnome-keyring stack is very broken. Sure, you can force it to compile. But it almost certainly won't work right at runtime. See https://bugzilla.gnome.org/show_bug.cgi?id=745843#c3
This is to the point that upstream removed support for gpg agent a few days ago. Imho, all work that intends to help fix issues like this should be taken to upstream directly, they need help as maintainer as little time to do the work himself.
Though I do understand this leaving things as they are will cause unintentional downgrades of GnuPG due to the fact that the latest evolution update now depends on libcryptui. At least for this use case (I'm using KDE) the combination of libcryptui/GnuPG 2.1 and evolution works as expected (GPG Sign/Encrypt) as far as I can tell. Maybe there could be some case of exemption (e.g. USE flag with a proper warning) when evolution is the sole user of libcryptui and similar cases.
*** Bug 551720 has been marked as a duplicate of this bug. ***
Um , per ChangeLog in opensuse package looks like they tested it for libcrypui part... but I need to find an upstream bug report or similar to forward that to them and hear their opinion: * Tue Dec 16 2014 dimstar@opensuse.org - Inject version 2.1 as acceptable gpg version into configure: GPG 2.1 is verified to be compatible and supported.
+ 27 Jun 2015; Pacho Ramos <pacho@gentoo.org> + +files/libcryptui-3.12.2-gnupg-2.1.patch, libcryptui-3.12.2.ebuild: + Support gnupg-2.1 building (#551822) +
