[Bug preprocessor/83063] [8 Regression] ICE on an invalid preprocessor snippet

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83063

--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Created attachment 43070
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=43070&action=edit
gcc8-pr83063.patch

WIP patch.  It still doesn't handle #__VA_OPT__(whatever) or #__VA_OPT__()
properly and there seems to be other issues.