Index: lib/ubsan/ubsan_flags.cc
===================================================================
--- lib/ubsan/ubsan_flags.cc
+++ lib/ubsan/ubsan_flags.cc
@@ -45,6 +45,7 @@
     CommonFlags cf;
     cf.CopyFrom(*common_flags());
     cf.print_summary = false;
+    cf.external_symbolizer_path = GetEnv("UBSAN_SYMBOLIZER_PATH");
     OverrideCommonFlags(cf);
   }