A SMLoc allows MCStreamer to report location-aware diagnostics, which
were previously done by adding SMLoc to various methods (e.g. emit*) in an ad-hoc way.
Since the file:line is most important, the column is less important and
the start token location suffices in many cases, this patch reverts
// old symbol-binding-changed.s:6:8: error: local changed binding to STB_GLOBAL .globl local ^ // new symbol-binding-changed.s:6:1: error: local changed binding to STB_GLOBAL .globl local ^