Test CircleCI with CLANG-10 (#7025)

Summary:
It's useful to build RocksDB using a more recent clang version in CI. Add a CircleCI build and fix some issues with it.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/7025

Test Plan: See all tests pass.

Reviewed By: pdillinger

Differential Revision: D22215700

fbshipit-source-id: 914a729c2cd3f3ac4a627cc0ac58d4691dca2168

.circleci/config.yml

@@ -57,6 +57,18 @@ jobs:
       - run: sudo apt-get install -y clang
       - run: CC=clang CXX=clang++ USE_CLANG=1 PORTABLE=1 make all -j32
 
+  build-linux-clang10-no-test:
+    machine:
+      image: ubuntu-1604:201903-01
+    resource_class: 2xlarge
+    steps:
+      - checkout # check out the code in the project directory
+      - run: sudo sh -c 'echo "deb http://apt.llvm.org/xenial/ llvm-toolchain-xenial-10 main" >> /etc/apt/sources.list'
+      - run: sudo sh -c 'echo "deb-src http://apt.llvm.org/xenial/ llvm-toolchain-xenial-10 main" >> /etc/apt/sources.list'
+      - run: sudo apt-get update -y
+      - run: sudo apt-get install -y clang-10
+      - run: CC=clang-10 CXX=clang++-10 ROCKSDB_DISABLE_ALIGNED_NEW=1 USE_CLANG=1 make all -j32 # aligned new doesn't work for reason we haven't figured out
+
   build-linux-cmake:
     machine:
       image: ubuntu-1604:201903-01
@@ -125,6 +137,9 @@ workflows:
   build-linux-clang-no-test:
     jobs:
       - build-linux-clang-no-test
+  build-linux-clang10-no-test:
+    jobs:
+      - build-linux-clang10-no-test
   build-linux-cmake:
     jobs:
       - build-linux-cmake

db/db_iter_stress_test.cc

@@ -97,7 +97,8 @@ struct StressTestIterator : public InternalIterator {
 
   bool MaybeFail() {
     if (rnd->Next() >=
-        std::numeric_limits<uint64_t>::max() * error_probability) {
+        static_cast<double>(std::numeric_limits<uint64_t>::max()) *
+            error_probability) {
       return false;
     }
     if (rnd->Next() % 2) {
@@ -114,7 +115,8 @@ struct StressTestIterator : public InternalIterator {
 
   void MaybeMutate() {
     if (rnd->Next() >=
-        std::numeric_limits<uint64_t>::max() * mutation_probability) {
+        static_cast<double>(std::numeric_limits<uint64_t>::max()) *
+            mutation_probability) {
       return;
     }
     do {
@@ -126,8 +128,9 @@ struct StressTestIterator : public InternalIterator {
       if (data->hidden.empty()) {
         hide_probability = 1;
       }
-      bool do_hide =
-          rnd->Next() < std::numeric_limits<uint64_t>::max() * hide_probability;
+      bool do_hide = rnd->Next() <
+                     static_cast<double>(std::numeric_limits<uint64_t>::max()) *
+                         hide_probability;
       if (do_hide) {
         // Hide a random entry.
         size_t idx = rnd->Next() % data->entries.size();

db/db_options_test.cc

@@ -39,7 +39,7 @@ class DBOptionsTest : public DBTestBase {
     std::unordered_map<std::string, std::string> options_map;
     StringToMap(options_str, &options_map);
     std::unordered_map<std::string, std::string> mutable_map;
-    for (const auto opt : db_options_type_info) {
+    for (const auto& opt : db_options_type_info) {
       if (opt.second.IsMutable() && opt.second.ShouldSerialize()) {
         mutable_map[opt.first] = options_map[opt.first];
       }
@@ -57,7 +57,7 @@ class DBOptionsTest : public DBTestBase {
     std::unordered_map<std::string, std::string> options_map;
     StringToMap(options_str, &options_map);
     std::unordered_map<std::string, std::string> mutable_map;
-    for (const auto opt : cf_options_type_info) {
+    for (const auto& opt : cf_options_type_info) {
       if (opt.second.IsMutable() && opt.second.ShouldSerialize()) {
         mutable_map[opt.first] = options_map[opt.first];
       }

env/env_test.cc

@@ -1120,7 +1120,7 @@ TEST_P(EnvPosixTestWithParam, RandomAccessUniqueIDConcurrent) {
 
     // Collect and check whether the IDs are unique.
     std::unordered_set<std::string> ids;
-    for (const std::string fname : fnames) {
+    for (const std::string& fname : fnames) {
       std::unique_ptr<RandomAccessFile> file;
       std::string unique_id;
       ASSERT_OK(env_->NewRandomAccessFile(fname, &file, soptions));
@@ -1134,7 +1134,7 @@ TEST_P(EnvPosixTestWithParam, RandomAccessUniqueIDConcurrent) {
     }
 
     // Delete the files
-    for (const std::string fname : fnames) {
+    for (const std::string& fname : fnames) {
       ASSERT_OK(env_->DeleteFile(fname));
     }
 

options/options_helper.cc

@@ -656,7 +656,7 @@ Status GetStringFromStruct(
     std::string* opt_string) {
   assert(opt_string);
   opt_string->clear();
-  for (const auto iter : type_info) {
+  for (const auto& iter : type_info) {
     const auto& opt_info = iter.second;
     // If the option is no longer used in rocksdb and marked as deprecated,
     // we skip it in the serialization.

table/table_test.cc

@@ -228,7 +228,7 @@ class BlockConstructor: public Constructor {
     block_ = nullptr;
     BlockBuilder builder(table_options.block_restart_interval);
 
-    for (const auto kv : kv_map) {
+    for (const auto& kv : kv_map) {
       builder.Add(kv.first, kv.second);
     }
     // Open the block
@@ -352,7 +352,7 @@ class TableConstructor: public Constructor {
         TablePropertiesCollectorFactory::Context::kUnknownColumnFamily,
         file_writer_.get()));
 
-    for (const auto kv : kv_map) {
+    for (const auto& kv : kv_map) {
       if (convert_to_internal_key_) {
         ParsedInternalKey ikey(kv.first, kMaxSequenceNumber, kTypeValue);
         std::string encoded;
@@ -487,7 +487,7 @@ class MemTableConstructor: public Constructor {
                              kMaxSequenceNumber, 0 /* column_family_id */);
     memtable_->Ref();
     int seq = 1;
-    for (const auto kv : kv_map) {
+    for (const auto& kv : kv_map) {
       memtable_->Add(seq, kTypeValue, kv.first, kv.second);
       seq++;
     }
@@ -548,7 +548,7 @@ class DBConstructor: public Constructor {
     delete db_;
     db_ = nullptr;
     NewDB();
-    for (const auto kv : kv_map) {
+    for (const auto& kv : kv_map) {
       WriteBatch batch;
       batch.Put(kv.first, kv.second);
       EXPECT_TRUE(db_->Write(WriteOptions(), &batch).ok());
@@ -1226,7 +1226,7 @@ class FileChecksumTestHelper {
   }
 
   Status WriteKVAndFlushTable() {
-    for (const auto kv : kv_map_) {
+    for (const auto& kv : kv_map_) {
       if (convert_to_internal_key_) {
         ParsedInternalKey ikey(kv.first, kMaxSequenceNumber, kTypeValue);
         std::string encoded;

tools/ldb_cmd_test.cc

@@ -76,7 +76,7 @@ TEST_F(LdbCmdTest, HexToStringBadInputs) {
   const vector<string> badInputs = {
       "0xZZ", "123", "0xx5", "0x111G", "0x123", "Ox12", "0xT", "0x1Q1",
   };
-  for (const auto badInput : badInputs) {
+  for (const auto& badInput : badInputs) {
     try {
       ROCKSDB_NAMESPACE::LDBCommand::HexToString(badInput);
       std::cerr << "Should fail on bad hex value: " << badInput << "\n";