[rfc] Clear some global variables when reloading object files

[Mark Kettenis]

> Date: Thu, 3 Aug 2006 17:46:42 -0400
> From: Daniel Jacobowitz <drow@false.org>
> 
> Mark, I encountered a problem today with expression_context_block that
> sounded exactly like what you encountered with innermost_block.  I
> suspect the right thing to do would be to clean up the global variables
> entirely, but I agree that it would be a terrible mess to untangle,
> and this seems like the next best thing.  What do you think?

Looks reasonable to me.

> 2006-08-03  Daniel Jacobowitz  <dan@codesourcery.com>
> 
> 	* Makefile.in (objfiles.o, symfile.o): Update.
> 	* objfiles.c: Include "expression.h" and "parser-defs.h".
> 	(free_objfile): Clear global blocks.
> 	* symfile.c: Include "parser-defs.h".
> 	(clear_symtab_users): Clear global blocks.