gdb/

gdb/
	* stack.c (return_command <retval_exp>): New variables retval_expr
	and old_chain.  Inline parse_and_eval to initialize retval_expr.  Check
	RETVAL_EXPR for UNOP_CAST and set RETURN_TYPE to the RETURN_VALUE type
	if RETURN_TYPE is NULL.

gdb/doc/
	* gdb.texinfo (Returning): New description for missing debug info.

gdb/testsuite/
	* gdb.base/return-nodebug.exp, gdb.base/return-nodebug.c: New.