See tracker bug.
newlib is a c library replacement for embedded systems; it also disables automatic stripping. On the positive side, the line with prepallstrip is commented out in all ebuilds already...
The bug has been referenced in the following commit(s): https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=10b92cbbf831284ec9b9d8aeab93c8d1c9ddf4fe commit 10b92cbbf831284ec9b9d8aeab93c8d1c9ddf4fe Author: Sergei Trofimovich <slyfox@gentoo.org> AuthorDate: 2018-11-25 14:54:43 +0000 Commit: Sergei Trofimovich <slyfox@gentoo.org> CommitDate: 2018-11-25 15:13:19 +0000 sys-libs/newlib: drop comment mentioning prepallstrip() The comment still manages to confuse people. Let's drop it. Bug: https://bugs.gentoo.org/587298 Package-Manager: Portage-2.3.52, Repoman-2.3.12 Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org> sys-libs/newlib/newlib-2.0.0.ebuild | 3 +-- sys-libs/newlib/newlib-2.1.0.ebuild | 3 +-- sys-libs/newlib/newlib-2.2.0.20150423.ebuild | 3 +-- sys-libs/newlib/newlib-2.2.0.ebuild | 3 +-- sys-libs/newlib/newlib-2.3.0.20160104.ebuild | 3 +-- sys-libs/newlib/newlib-2.4.0.ebuild | 3 +-- sys-libs/newlib/newlib-2.5.0.ebuild | 3 +-- sys-libs/newlib/newlib-9999.ebuild | 3 +-- 8 files changed, 8 insertions(+), 16 deletions(-)