Hi,

The emacs will be extremely slow after I first time enable the
semantic mode and open a simple C source file which includes the
stdio.h.
I find the semantic mode will try to analyse the chained header files,
by calling the function (semantic-find-file-noselect ...) to open the
file and analyse its content, while the `find-file-hook` may have many
heavy functions.
Disabling the `find-file-hook` do have great performance improvement
for semantic mode.
Please help review this patch. Thanks

Best regards
Lin