previous to sys-libs/binutils-libs-2.25.1-r2 and sys-devel/binutils-config-5-r2 the file dmangle.h was available in /usr/include. Now it ships in /usr/include/libiberty which appears to be non standard. Can we keep this file available in /usr/include?
it's always been available via libiberty/ because libiberty is the sub-package that owns/installs the header. the reason it was available in /usr/include/ directly in the past was we additionally symlinked it (and a few other headers). not for any real good reason, more of a historical wart. i don't know about your "non-standard" claim -- it's what upstream binutils does, and apparently also what Debian does. i don't see any failing packages listed here, so i'm guessing it's just your own code. change it to use libiberty/ and move on.
for completeness, the failing package was already listed in "see also" and I'll link it here: https://bugs.gentoo.org/show_bug.cgi?id=561978 You have already given me what I wanted, an official ruling on how to fix my bug. I can and will use libiberty/demangle.h. Thanks.
(In reply to Rick Farina (Zero_Chaos) from comment #2) ah, i only saw the blockers list. sorry about that.