[Bug c++/54928] Infinite output with after ICE with macro

[manu at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54928

--- Comment #8 from Manuel López-Ibáñez <manu at gcc dot gnu.org> 2012-10-16 18:05:52 UTC ---
Created attachment 28457
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=28457
better fix

The code is re-using the diagnostic passed as an argument to produce new
diagnostics, and by saving/reloading values on it. But we actually only need to
modify things once, and if we use a new diagnostic struct, we don't need to
touch the original.

Of course, we should still not print the caret and macro expansion in
internal_error, but that is a bit more complicated.