2007-11-1  George Helffrich  <ghfbsd@gly.bris.ac.uk>

	* dbxout.c (dbxout_symbol_location, dbxout_syms): Output stabs for
	symbols in .comm to use the gdb-supported N_BCOMM/N_ECOMM mechanism.
	Some systems (e.g. Darwin) will not relocate SYMBOL+offset expressions
	in stabs, making the traditional N_LCSYM mechanism unusable.
        (dbxout_common_name, dbxout_common_check): New routines.

	*dwarf2out.c (gen_decl_die, decls_for_scope): Output DWARF DIE
	for symbols in Fortran common using DW_AT_common_block.  This allows
	some GDB ports (e.g. Darwin) to relocate references to COMMON data
	properly.
	(add_pubname_string, add_pubname, dw_expand_expr, common_check): New
	routines for ditto.