No talking please.
I suggest not doing anything here. * In 13.0 profiles, >=ICU 59 is masked. * In 17.0 profiles, <GCC-6 is masked. I.e., in current profiles the problem should not appear, and in future profiles it will be gone. If you insist on making your package buildable with ICU 59 and old GCC, adding -std=c++11 (or newer) to CFLAGS somewhere should do the trick. However, the intention of the whole profiles construct is to make such liberal sprinkling of ebuild complications unnecessary.
should we close the bugs then?
Not needed anymore.