From 1f0b6e13bdb1107e25f2898c4c785ee12d980ac5 Mon Sep 17 00:00:00 2001
From: TianlinZhao <tianlinzhao@google.com>
Date: Thu, 30 Jul 2020 19:52:12 -0400
Subject: [PATCH] tracer

---
 api/include/opentelemetry/trace/default_span.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/api/include/opentelemetry/trace/default_span.h b/api/include/opentelemetry/trace/default_span.h
index f5a4cfff11..0adfe60079 100644
--- a/api/include/opentelemetry/trace/default_span.h
+++ b/api/include/opentelemetry/trace/default_span.h
@@ -8,6 +8,7 @@
 #define pass
 OPENTELEMETRY_BEGIN_NAMESPACE
 namespace trace {
+class DefaultTracer;
 class DefaultSpan: public Span {
   public:
     // Returns an invalid span.