[Bug other/64452] [4.8/4.9/5.0 Regression] ICE in avr-gcc when passing struct member to varargs function

[gjl at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64452

--- Comment #1 from Georg-Johann Lay <gjl at gcc dot gnu.org> ---
Created attachment 34787
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=34787&action=edit
Tentative patch for 5.0