* include/cpplib.h (struct cpp_options): Add canonical_system_headers.
* files.c (find_file_in_dir): Call maybe_shorter_path() only if
canonical_system_headers is set.
* init.c (cpp_create_reader): Initialize canonical_system_headers.
* configure.ac: Add new --enable-canonical-system-headers.
* configure: Regenerate.
* config.in: Regenerate.
* doc/cppopts.texi: Document -f[no-]canonical-system-headers.
* doc/install.texi: Document --enable-canonical-system-headers.
* c.opt: Add f[no-]canonical-system-headers.
* c-opts.c (c_common_handle_option): Handle
OPT_fcanonical_system_headers.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@193569
138bc75d-0d04-0410-961f-
82ee72b054a4