In new stable 'eautoreconf' command was added to src_prepare without adding automake to DEPEND, so build fails:
>>> Preparing source in /var/package-manager/tmp/portage/net-libs/libgadu-1.11.4/work/libgadu-1.11.4 ...
* Running eautoreconf in '/var/package-manager/tmp/portage/net-libs/libgadu-1.11.4/work/libgadu-1.11.4' ...
* ERROR: net-libs/libgadu-1.11.4::gentoo failed (prepare phase):
* Cannot find the latest automake! Tried 1.13:1.13
After installing automake libgadu builds fine.
Thanks for reporting.