Options initialization rearrangement

[Joseph S. Myers]

On Sat, 9 Oct 2010, Richard Sandiford wrote:

> "Joseph S. Myers" <joseph@codesourcery.com> writes:
> > 	* configure.ac (tm_include_list): Include flags.h instead of
> > 	options.h.
> 
> Not sure if you're already aware, but this change breaks the build
> for MIPS.  flags.h includes some state that is in the target_flag_state
> structure, but SWITCHABLE_TARGET is no longer defined appropriately.
> I suppose target_flag_state now belongs in a different header file.

My inclination would be that a fix should put the types from flags.h (that 
are the reason that it needs to be included in options.h) in a separate 
flag-types.h header, included by both flags.h and options.h, so that 
options.h can be included on its own again, and then go back to having 
options.h used by tm.h (revert those configure and TM_H changes).  The 
general idea is inspired by 
<http://gcc.gnu.org/ml/gcc-patches/2010-10/msg00754.html>, but I don't 
think there should be much interaction between that fix and the 
HeaderInclude changes in that patch.

-- 
Joseph S. Myers
joseph@codesourcery.com