ld: be less picky about bad line number info
ld: be less picky about bad line number info

Fixes issue 1175.

R=lvd
CC=golang-dev
http://codereview.appspot.com/2439041
abustany/go,abustany/go,abustany/go,abustany/go,abustany/go,abustany/go,abustany/go