For those who comment out "strip-flags" in the glibc ebuild, "strip-flags" should include "-ffunction-sections" as glibc build fails with this flag. Reproducible: Always Steps to Reproduce:
I mean "filter-flags" should include it. Doh.
You uncomment strip-flags, means you are prepared to take the risk. Only way out, is to get flags tested to be included in 'stable' flags for strip-flags