Created attachment 898325 [details] build.log Fails to build with -flto on musl-llvm system. Building without -flto works.
Created attachment 898326 [details] emerge --info
Not specific to musl. Same error on llvm with glibc. Also reported by https://www.reddit.com/r/Gentoo/comments/1eodr9i/ldlld_error_undefined_symbol_truncsfbf2.