use -Werror=missing-field-initializers, to closer match MyRocks build

Summary:
myrocks seems to build rocksdb using
-Wmissing-field-initializers (and treats warnings as errors).  This diff
adds that flag to the rocksdb build, and fixes the compilation failures
that result.  I have not checked for any other differences in the build
flags for rocksdb build as part of myrocks.

Test Plan: make check

Reviewers: sdong, rven

Reviewed By: rven

Subscribers: dhruba

Differential Revision: https://reviews.facebook.net/D52443

Makefile

@@ -192,7 +192,7 @@ ifndef DISABLE_WARNING_AS_ERROR
 endif
 
 CFLAGS += $(WARNING_FLAGS) -I. -I./include $(PLATFORM_CCFLAGS) $(OPT)
-CXXFLAGS += $(WARNING_FLAGS) -I. -I./include $(PLATFORM_CXXFLAGS) $(OPT) -Woverloaded-virtual -Wnon-virtual-dtor -Wno-missing-field-initializers
+CXXFLAGS += $(WARNING_FLAGS) -I. -I./include $(PLATFORM_CXXFLAGS) $(OPT) -Woverloaded-virtual -Wnon-virtual-dtor -Werror=missing-field-initializers
 
 LDFLAGS += $(PLATFORM_LDFLAGS)
 

db/column_family_test.cc

@@ -1990,10 +1990,10 @@ TEST_F(ColumnFamilyTest, FlushAndDropRaceCondition) {
   Reopen({options, options});
 
   rocksdb::SyncPoint::GetInstance()->LoadDependency(
-      {{"VersionSet::LogAndApply::ColumnFamilyDrop:1"
+      {{"VersionSet::LogAndApply::ColumnFamilyDrop:1",
         "FlushJob::InstallResults"},
        {"FlushJob::InstallResults",
-        "VersionSet::LogAndApply::ColumnFamilyDrop:2", }});
+        "VersionSet::LogAndApply::ColumnFamilyDrop:2"}});
 
   rocksdb::SyncPoint::GetInstance()->EnableProcessing();
   test::SleepingBackgroundTask sleeping_task;

db/db_impl.cc

@@ -4383,7 +4383,7 @@ Status DBImpl::WriteImpl(const WriteOptions& write_options,
             &flush_scheduler_, write_options.ignore_missing_column_families,
             0 /*log_number*/, this, false /*dont_filter_deletes*/);
       } else {
-        WriteThread::ParallelGroup pg{};
+        WriteThread::ParallelGroup pg;
         pg.leader = &w;
         pg.last_writer = last_writer;
         pg.early_exit_allowed = !need_log_sync;

db/db_test.cc

@@ -5653,7 +5653,7 @@ TEST_F(DBTest, GroupCommitTest) {
     ASSERT_TRUE(!itr->Valid());
     delete itr;
 
-    HistogramData hist_data = {0};
+    HistogramData hist_data = {0, 0, 0, 0, 0};
     options.statistics->histogramData(DB_WRITE, &hist_data);
     ASSERT_GT(hist_data.average, 0.0);
   } while (ChangeOptions(kSkipNoSeekToLast));

db/write_thread.cc

@@ -213,7 +213,7 @@ void WriteThread::CreateMissingNewerLinks(Writer* head) {
 }
 
 void WriteThread::JoinBatchGroup(Writer* w) {
-  static AdaptationContext ctx{"JoinBatchGroup"};
+  static AdaptationContext ctx("JoinBatchGroup");
 
   assert(w->batch != nullptr);
   bool linked_as_leader;
@@ -323,7 +323,7 @@ void WriteThread::LaunchParallelFollowers(ParallelGroup* pg,
 }
 
 bool WriteThread::CompleteParallelWorker(Writer* w) {
-  static AdaptationContext ctx{"CompleteParallelWorker"};
+  static AdaptationContext ctx("CompleteParallelWorker");
 
   auto* pg = w->parallel_group;
   if (!w->status.ok()) {
@@ -419,7 +419,7 @@ void WriteThread::ExitAsBatchGroupLeader(Writer* leader, Writer* last_writer,
 }
 
 void WriteThread::EnterUnbatched(Writer* w, InstrumentedMutex* mu) {
-  static AdaptationContext ctx{"EnterUnbatched"};
+  static AdaptationContext ctx("EnterUnbatched");
 
   assert(w->batch == nullptr);
   bool linked_as_leader;

db/write_thread.h

@@ -207,6 +207,8 @@ class WriteThread {
   struct AdaptationContext {
     const char* name;
     std::atomic<int32_t> value;
+
+    explicit AdaptationContext(const char* name0) : name(name0), value(0) {}
   };
 
  private:

table/table_test.cc

@@ -1998,7 +1998,7 @@ TEST_F(HarnessTest, Randomized) {
 #ifndef ROCKSDB_LITE
 TEST_F(HarnessTest, RandomizedLongDB) {
   Random rnd(test::RandomSeed());
-  TestArgs args = { DB_TEST, false, 16, kNoCompression, 0 };
+  TestArgs args = {DB_TEST, false, 16, kNoCompression, 0, false};
   Init(args);
   int num_entries = 100000;
   for (int e = 0; e < num_entries; e++) {