Throw exceptions from rs6000 unwinder

gdb:

2017-07-21  Yao Qi  <yao.qi@linaro.org>

	* rs6000-tdep.c (struct rs6000_frame_cache) <base_p>: Remove.
	(rs6000_frame_cache): Don't catch exceptions.
	(rs6000_frame_this_id): Don't check info->base_p.
	(rs6000_epilogue_frame_this_id): Likewise.
1 file changed