Gentoo's Bugzilla –
Attachment 704121 Details for
Bug 786981sys-fs/dd-rescue-1.99.10: fails to build on ppc ( /usr/lib/gcc/powerpc-unknown-linux-gnu/10.2.0/include/altivec.h:34:2: error: #error Use the "-maltivec" flag to enable PowerPC AltiVec support)