build: fix IWYU error in instruments.h (open-telemetry#1555)

yxue · Dec 5, 2022 · fdf2ad7 · fdf2ad7
1 parent 95e9e0e
commit fdf2ad7
Showing 1 changed file with 1 addition and 0 deletions.
diff --git a/sdk/include/opentelemetry/sdk/metrics/instruments.h b/sdk/include/opentelemetry/sdk/metrics/instruments.h
@@ -3,6 +3,7 @@
 
 #pragma once
 #ifndef ENABLE_METRICS_PREVIEW
+#  include <functional>
 #  include "opentelemetry/sdk/common/attribute_utils.h"
 OPENTELEMETRY_BEGIN_NAMESPACE
 namespace sdk