[Bug ipa/84628] attribute(warning/error) functions should not be merged together

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84628

--- Comment #10 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Created attachment 43533
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=43533&action=edit
gcc8-pr84628.patch

Untested fix.