https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81037
--- Comment #9 from Jack Howarth <howarth.at.gcc at gmail dot com> --- Note that the main deviation from the previous back porting for gcc-6-branch is that the ipa-icf-gimple.c source file must define INCLUDE_LIST since it is used in that file for gcc-5-branch unlike gcc-6-branch.
