Description of problem:


Version-Release number of selected component (if applicable):


How reproducible:


Steps to Reproduce:
1.
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Actual results:


Expected results:


Additional info:


src/mongo/db/repl/oplog_fetcher.cpp: In function 'mongo::StatusWith<boost::optional<mongo::rpc::OplogQueryMetadata> > mongo::repl::{anonymous}::parseOplogQueryMetadata(mongo::Fetcher::QueryResponse)':
src/mongo/db/repl/oplog_fetcher.cpp:248:93: error: no matching function for call to 'make_optional<mongo::rpc::OplogQueryMetadata>(mongo::rpc::OplogQueryMetadata&)'
         oqMetadata = boost::make_optional<rpc::OplogQueryMetadata>(metadataResult.getValue());
                                                                                             ^
In file included from /usr/include/boost/optional.hpp:15:0,
                 from src/mongo/base/status_with.h:30,
                 from src/mongo/db/repl/oplog_fetcher.h:34,
                 from src/mongo/db/repl/oplog_fetcher.cpp:33:
/usr/include/boost/optional/optional.hpp:1367:56: note: candidate: template<class T> boost::optional<typename boost::decay<T>::type> boost::make_optional(T&&)
 optional<BOOST_DEDUCED_TYPENAME boost::decay<T>::type> make_optional ( T && v  )
                                                        ^~~~~~~~~~~~~
/usr/include/boost/optional/optional.hpp:1367:56: note:   template argument deduction/substitution failed:
The error is:

src/mongo/db/repl/oplog_fetcher.cpp:248:91: note:   cannot convert 'metadataResult.mongo::StatusWith<mongo::rpc::OplogQueryMetadata>::getValue()' (type 'mongo::rpc::OplogQueryMetadata') to type 'mongo::rpc::OplogQueryMetadata&&'
         oqMetadata = boost::make_optional<rpc::OplogQueryMetadata>(metadataResult.getValue());
                                                                    ~~~~~~~~~~~~~~~~~~~~~~~^~
In file included from /usr/include/boost/optional.hpp:15:0,
                 from src/mongo/base/status_with.h:30,
                 from src/mongo/db/repl/oplog_fetcher.h:34,
                 from src/mongo/db/repl/oplog_fetcher.cpp:33:
/usr/include/boost/optional/optional.hpp:1375:56: note: candidate: template<class T> boost::optional<typename boost::decay<T>::type> boost::make_optional(bool, T&&)
 optional<BOOST_DEDUCED_TYPENAME boost::decay<T>::type> make_optional ( bool cond, T && v )
                                                        ^~~~~~~~~~~~~
/usr/include/boost/optional/optional.hpp:1375:56: note:   template argument deduction/substitution failed:
src/mongo/db/repl/oplog_fetcher.cpp:248:93: note:   candidate expects 2 arguments, 1 provided
         oqMetadata = boost::make_optional<rpc::OplogQueryMetadata>(metadataResult.getValue());
                                                                                             ^

This code is dumb, the point of make_optional(x) is to deduce the type from 'x', so saying make_optional<T>(x) to override it makes no sense, and doesn't even compile with the latest version of boost (because boost::optional now follows the same design as std::optional).


The upstream bug is https://jira.mongodb.org/browse/SERVER-32516

The fix is:

--- mongo-r3.6.2/src/mongo/db/repl/oplog_fetcher.cpp~   2018-01-30 18:19:15.398613407 +0000
+++ mongo-r3.6.2/src/mongo/db/repl/oplog_fetcher.cpp    2018-01-30 18:19:43.245561408 +0000
@@ -245,7 +245,7 @@
         if (!metadataResult.isOK()) {
             return metadataResult.getStatus();
         }
-        oqMetadata = boost::make_optional<rpc::OplogQueryMetadata>(metadataResult.getValue());
+        oqMetadata = boost::make_optional(metadataResult.getValue());
     }
     return oqMetadata;
 }