[Bug c++/52974] Canonicalize include paths in diagnostics

[manu at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52974

--- Comment #4 from Manuel López-Ibáñez <manu at gcc dot gnu.org> 2012-04-15 15:31:46 UTC ---
Created attachment 27160
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=27160
patch

This patch implements the shortening in line-map.c. It seems more general fix
than touching the default include paths.

If it looks ok to you, I will submit it properly.