Merge branch 'go_caller_filepath'.
diff --git a/go/build.go b/go/build.go
index 095efb2..03935fc 100644
--- a/go/build.go
+++ b/go/build.go
@@ -42,6 +42,9 @@
 
 func init() {
 	_, buildGO, _, _ = runtime.Caller(1)
+	if buildGO == "<autogenerated>" {
+		_, buildGO, _, _ = runtime.Caller(0)
+	}
 	buildDir = path.Dir(buildGO)
 	hostSrcDir = path.Join(buildDir, "../c/src")
 	configGO = path.Join(buildDir, "lucy", "config.go")