https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98323
--- Comment #3 from David Binderman <dcb314 at hotmail dot com> --- (In reply to Nathan Sidwell from comment #2) > stupid underspecified offsetof I did try commenting out the offending block of code and a re-build and got further errors ;-< I don't know if you have access to clang, but if you don't, may I be so bold as to suggest you install a copy and, if you have the time, attempt a full build with clang ? That should flush out all the gcc specific code in your recent changes. Excellent compiler, BTW.