* breakpoint.c (breakpoint_1): Walk the breakpoint chain to decide if

	* breakpoint.c (breakpoint_1):  Walk the breakpoint chain to decide if
	we have breakpoints or watchpoints as we might have to ignore internal
	breakpoints.

	Fix gdb core dumps after `file newfile' commands.
	* symtab.h, symfile.c (clear_symtab_users):  New routine which
	unconditionally clears symtab users. clear_symtab_users_once
	commented out as it was a noop anyway.
	* objfiles.c (free_objfile):  Don't call clear_symtab_users_once.
	* objfiles.c (free_all_objfiles), symfile.c (new_symfile_objfile),
	xcoffexec.c (exec_close):  Call clear_symtab_users if necessary.
	* symfile.c (syms_from_objfile):  Install cleanups for errors during
	symbol reading.
	* coffread.c, dbxread.c, mipsread.c, xcoffread.c (*_symfile_read):
	Lint cleanup code, call do_cleanups explicitly.
	* symfile.c (symbol_file_add):  Call new_symfile_objfile and
	reinit_frame_cache _after_ the new symbols are read in.