Created attachment 3931 [details] diffoscope output that corroborates the claim. "bushbug" reports CFLAGS used to build the bash image. The flags contain hardcoded path to the host build environment, via the "-fdebug-prefix-map=", hence two builds in two different folders will be binary different. Fix this by removing all "-fdebug-prefix-map" flags. (brought in via DEBUG_PREFIX_MAP).
Patch merged http://git.yoctoproject.org/cgit/cgit.cgi/poky/commit/?id=dabbfe23de0615a958fac31b83684ade024cf17d