Use of auto that causes a copy
Unnecessary object copies can affect performance. Using the auto keyword without an & causes a copy.
/data/mci/22bd5cb6273c9c571686198c9f6023af/bazel_cache/3d8c86e2cd3c28a487a62d019e05fed8/execroot/_main/src/mongo/db/pipeline/document_source_facet.cpp:243: AUTO_CAUSES_COPY 175376 Using the "auto" keyword without an "&" causes the copy of an object of type "std::vector<mongo::Value, std::allocator<mongo::Value> >".
/data/mci/22bd5cb6273c9c571686198c9f6023af/bazel_cache/3d8c86e2cd3c28a487a62d019e05fed8/execroot/_main/src/mongo/db/pipeline/document_source_facet.cpp:243: AUTO_CAUSES_COPY 175376 The variable "explain" has a non-"const" type, however its value is never changed.