Revert to C++17 build

cpp/CMakeLists.txt

@@ -3,7 +3,7 @@ cmake_minimum_required(VERSION 3.21) # TARGET_RUNTIME_DLLS
 # Make the `project` command handle the version of the project.
 cmake_policy(SET CMP0048 NEW)
 
-set(CMAKE_CXX_STANDARD 20)
+set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 # We do not need any compilers' extensions, so we disable them.
 set(CMAKE_CXX_EXTENSIONS OFF)

cpp/arcticdb/CMakeLists.txt

@@ -347,7 +347,6 @@ set(arcticdb_srcs
         util/memory_mapped_file.hpp
         util/name_validation.hpp
         util/offset_string.hpp
-        util/offset_string.hpp
         util/optional_defaults.hpp
         util/pb_util.hpp
         util/preconditions.hpp
@@ -473,7 +472,6 @@ set(arcticdb_srcs
         util/memory_mapped_file.hpp
         util/name_validation.cpp
         util/offset_string.cpp
-        util/offset_string.cpp
         util/sparse_utils.cpp
         util/string_utils.cpp
         util/trace.cpp
@@ -488,7 +486,7 @@ set(arcticdb_srcs
         version/symbol_list.cpp
         version/version_map_batch_methods.cpp
         storage/s3/ec2_utils.cpp
-)
+        storage/lmdb/lmdb.hpp)
 
 if(${ARCTICDB_INCLUDE_ROCKSDB})
     list (APPEND arcticdb_srcs
@@ -680,6 +678,7 @@ target_include_directories(arcticdb_python PRIVATE
         ${LIBMONGOCXX_STATIC_INCLUDE_DIRS}
         ${LIBBSONCXX_STATIC_INCLUDE_DIRS}
         ${BITMAGIC_INCLUDE_DIRS}
+        ${LMDB_LIBRARIES}
         )
 
 

cpp/arcticdb/column_store/column.hpp

@@ -28,7 +28,6 @@
 #include <pybind11/pybind11.h>
 #include <pybind11/numpy.h>
 
-#include <concepts>
 #include <numeric>
 #include <optional>
 
@@ -677,7 +676,7 @@ class Column {
     template <
             typename input_tdt,
             typename functor>
-    requires std::is_invocable_r_v<void, functor, typename input_tdt::DataTypeTag::raw_type>
+    // requires std::is_invocable_r_v<void, functor, typename input_tdt::DataTypeTag::raw_type> //TODO reinstate with C++20
     static void for_each(const Column& input_column, functor&& f) {
         auto input_data = input_column.data();
         std::for_each(input_data.cbegin<input_tdt>(), input_data.cend<input_tdt>(), std::forward<functor>(f));
@@ -686,7 +685,7 @@ class Column {
     template <
             typename input_tdt,
             typename functor>
-    requires std::is_invocable_r_v<void, functor, typename ColumnData::Enumeration<typename input_tdt::DataTypeTag::raw_type>>
+    //requires std::is_invocable_r_v<void, functor, typename ColumnData::Enumeration<typename input_tdt::DataTypeTag::raw_type>>
     static void for_each_enumerated(const Column& input_column, functor&& f) {
         auto input_data = input_column.data();
         if (input_column.is_sparse()) {
@@ -702,7 +701,7 @@ class Column {
         typename input_tdt,
         typename output_tdt,
         typename functor>
-    requires std::is_invocable_r_v<typename output_tdt::DataTypeTag::raw_type, functor, typename input_tdt::DataTypeTag::raw_type>
+    //  requires std::is_invocable_r_v<typename output_tdt::DataTypeTag::raw_type, functor, typename input_tdt::DataTypeTag::raw_type>
     static void transform(const Column& input_column, Column& output_column, functor&& f) {
         auto input_data = input_column.data();
         initialise_output_column(input_column, output_column);
@@ -720,11 +719,11 @@ class Column {
             typename right_input_tdt,
             typename output_tdt,
             typename functor>
-    requires std::is_invocable_r_v<
+    /*requires std::is_invocable_r_v<
             typename output_tdt::DataTypeTag::raw_type,
             functor,
             typename left_input_tdt::DataTypeTag::raw_type,
-            typename right_input_tdt::DataTypeTag::raw_type>
+            typename right_input_tdt::DataTypeTag::raw_type>*/
     static void transform(const Column& left_input_column,
                           const Column& right_input_column,
                           Column& output_column,
@@ -783,7 +782,8 @@ class Column {
 
     template <
             typename input_tdt,
-            std::predicate<typename input_tdt::DataTypeTag::raw_type> functor>
+            typename functor>
+    // std::predicate<typename input_tdt::DataTypeTag::raw_type> functor>
     static void transform(const Column& input_column,
                           util::BitSet& output_bitset,
                           bool sparse_missing_value_output,
@@ -806,7 +806,8 @@ class Column {
     template <
             typename left_input_tdt,
             typename right_input_tdt,
-            std::relation<typename left_input_tdt::DataTypeTag::raw_type, typename right_input_tdt::DataTypeTag::raw_type> functor>
+            // std::relation<typename left_input_tdt::DataTypeTag::raw_type, typename right_input_tdt::DataTypeTag::raw_type> functor>
+            typename functor>
     static void transform(const Column& left_input_column,
                           const Column& right_input_column,
                           util::BitSet& output_bitset,

cpp/arcticdb/column_store/column_data.hpp

@@ -258,7 +258,7 @@ struct ColumnData {
             return data_.ptr_ == other.data_.ptr_;
         }
 
-        base_type::reference dereference() const {
+        typename base_type::reference dereference() const {
             if constexpr (iterator_type == IteratorType::ENUMERATED) {
                 return data_;
             } else {
@@ -270,7 +270,7 @@ struct ColumnData {
         ColumnData* parent_{nullptr};
         std::optional<TypedBlockData<TDT>> opt_block_{std::nullopt};
         std::size_t remaining_values_in_block_{0};
-        base_type::value_type data_;
+        typename base_type::value_type data_;
     };
 
     ColumnData(

cpp/arcticdb/log/log.cpp

@@ -33,16 +33,12 @@ namespace arcticdb::log {
 
 static const char* DefaultLogPattern = "%Y%m%d %H:%M:%S.%f %t %L %n | %v";
 
-
 namespace {
-    std::shared_ptr<Loggers> loggers_instance_;
-    std::once_flag loggers_init_flag_;
-}
-
-
-struct Loggers::Impl
-{
+std::shared_ptr<Loggers> loggers_instance_;
+std::once_flag loggers_init_flag_;
+} // namespace
 
+struct Loggers::Impl {
     std::mutex config_mutex_;
     std::unordered_map<std::string, spdlog::sink_ptr> sink_by_id_;
     std::unique_ptr<spdlog::logger> unconfigured_ = std::make_unique<spdlog::logger>("arcticdb",
@@ -70,7 +66,6 @@ struct Loggers::Impl
     spdlog::logger& logger_ref(std::unique_ptr<spdlog::logger>& src);
 };
 
-
 constexpr auto get_default_log_level() {
     return spdlog::level::info;
 }
@@ -128,15 +123,13 @@ namespace fs = std::filesystem;
 using SinkConf = arcticdb::proto::logger::SinkConfig;
 
 Loggers::Loggers()
-    : impl_(std::make_unique<Impl>())
-{
+        : impl_(std::make_unique<Impl>()) {
     impl_->unconfigured_->set_level(get_default_log_level());
 }
 
 Loggers::~Loggers() = default;
 
-Loggers& Loggers::instance()
-{
+Loggers& Loggers::instance() {
     std::call_once(loggers_init_flag_, &Loggers::init);
     return *loggers_instance_;
 }
@@ -204,7 +197,6 @@ void Loggers::flush_all() {
     snapshot().flush();
 }
 
-
 void Loggers::destroy_instance() {
     loggers_instance_.reset();
 }
@@ -213,7 +205,6 @@ void Loggers::init() {
     loggers_instance_ = std::make_shared<Loggers>();
 }
 
-
 namespace {
 std::string make_parent_dir(const std::string &p_str, std::string_view def_p_str) {
     fs::path p;
@@ -236,7 +227,6 @@ spdlog::logger& Loggers::Impl::logger_ref(std::unique_ptr<spdlog::logger>& src)
     return *unconfigured_;
 }
 
-
 bool Loggers::configure(const arcticdb::proto::logger::LoggersConfig &conf, bool force) {
     auto lock = std::scoped_lock(impl_->config_mutex_);
     if (!force && impl_->root_)
@@ -320,7 +310,6 @@ bool Loggers::configure(const arcticdb::proto::logger::LoggersConfig &conf, bool
     check_and_configure("symbol", "root", impl_->symbol_);
     check_and_configure("snapshot", "root", impl_->snapshot_);
 
-
     if (auto flush_sec = util::as_opt(conf.flush_interval_seconds()).value_or(1); flush_sec != 0) {
         impl_->periodic_worker_.emplace(
             [loggers = std::weak_ptr(loggers_instance_)]() {
@@ -332,7 +321,6 @@ bool Loggers::configure(const arcticdb::proto::logger::LoggersConfig &conf, bool
     return true;
 }
 
-
 void Loggers::Impl::configure_logger(
         const arcticdb::proto::logger::LoggerConfig &conf,
         const std::string &name,
@@ -354,18 +342,15 @@ void Loggers::Impl::configure_logger(
         logger = std::make_unique<spdlog::logger>(fq_name, sink_ptrs.begin(), sink_ptrs.end());
     }
 
-    if (!conf.pattern().empty()) {
+    if (!conf.pattern().empty())
         logger->set_pattern(conf.pattern());
-    }
-    else {
+    else
         logger->set_pattern(DefaultLogPattern);
-    }
 
-    if (conf.level() != 0) {
+    if (conf.level() != 0)
         logger->set_level(static_cast<spdlog::level::level_enum>(conf.level() - 1));
-    } else {
+    else
         logger->set_level(get_default_log_level());
-    }
 }
 
 }

cpp/arcticdb/pipeline/index_writer.hpp

@@ -17,7 +17,7 @@
 
 namespace arcticdb::pipelines::index {
 // TODO: change the name - something like KeysSegmentWriter or KeyAggragator or  better
-template<ValidIndex Index>
+template<typename Index>
 class IndexWriter {
     // All index segments are row-count indexed in the sense that the keys are
     // already ordered - they don't need an additional index

cpp/arcticdb/pipeline/input_tensor_frame.hpp

@@ -18,18 +18,6 @@ namespace arcticdb::pipelines {
 
 using namespace arcticdb::entity;
 
-/// @TODO Move to a separate "util" header
-template <typename T, typename... U>
-concept is_any_of = (std::same_as<T, U> || ...);
-
-template <typename IndexT>
-concept ValidIndex = is_any_of<
-    std::remove_cvref_t<std::remove_pointer_t<std::decay_t<IndexT>>>,
-    stream::TimeseriesIndex,
-    stream::RowCountIndex,
-    stream::TableIndex,
-    stream::EmptyIndex>;
-
 
 struct InputTensorFrame {
     InputTensorFrame() :

cpp/arcticdb/processing/clause.hpp

@@ -351,6 +351,13 @@ inline StreamDescriptor empty_descriptor(arcticdb::proto::descriptors::IndexDesc
 }
 
 struct NamedAggregator {
+    NamedAggregator(const std::string& s, const std::string& t, const std::string& v) :
+            aggregation_operator_(s),
+            input_column_name_(t),
+            output_column_name_(v){
+
+    }
+
     std::string aggregation_operator_;
     std::string input_column_name_;
     std::string output_column_name_;

cpp/arcticdb/processing/test/benchmark_clause.cpp

@@ -89,7 +89,6 @@ static void BM_merge_ordered(benchmark::State& state){
 }
 
 template <typename integer>
-requires std::integral<integer>
 void BM_hash_grouping_int(benchmark::State& state) {
     auto num_rows = state.range(0);
     auto num_unique_values = state.range(1);

cpp/arcticdb/storage/coalesced/multi_segment_utils.hpp

@@ -22,7 +22,7 @@ uint64_t get_symbol_prefix(const entity::StreamId& stream_id) {
     constexpr size_t begin = sizeof(InternalType) - sizeof(StorageType);
     StorageType data{};
     util::variant_match(stream_id,
-        [&data] (const entity::StringId& string_id) {
+        [&data, begin, end] (const entity::StringId& string_id) {
             auto* target = reinterpret_cast<char*>(&data);
             for(size_t p = begin, i = 0; p < end && i < string_id.size(); ++p, ++i) {
                 const auto c = string_id[i];

cpp/arcticdb/storage/lmdb/lmdb.hpp

@@ -0,0 +1,14 @@
+#pragma once
+
+// LMDB++ is using `std::is_pod` in `lmdb++.h`, which is deprecated as of C++20.
+// See: https://github.com/drycpp/lmdbxx/blob/0b43ca87d8cfabba392dfe884eb1edb83874de02/lmdb%2B%2B.h#L1068
+// See: https://en.cppreference.com/w/cpp/types/is_pod
+// This suppresses the warning.
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+#ifdef ARCTICDB_USING_CONDA
+#include <lmdb++.h>
+#else
+#include <third_party/lmdbcxx/lmdb++.h>
+#endif
+#pragma GCC diagnostic pop

cpp/arcticdb/storage/lmdb/lmdb_client_wrapper.hpp

@@ -12,18 +12,10 @@
 #include <arcticdb/entity/variant_key.hpp>
 #include <arcticdb/storage/storage_utils.hpp>
 
-// LMDB++ is using `std::is_pod` in `lmdb++.h`, which is deprecated as of C++20.
-// See: https://github.com/drycpp/lmdbxx/blob/0b43ca87d8cfabba392dfe884eb1edb83874de02/lmdb%2B%2B.h#L1068
-// See: https://en.cppreference.com/w/cpp/types/is_pod
-// This suppresses the warning.
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
-#ifdef ARCTICDB_USING_CONDA
-#include <lmdb++.h>
-#else
-#include <third_party/lmdbxx/lmdb++.h>
-#endif
-#pragma GCC diagnostic pop
+namespace lmdb {
+class txn;
+class dbi;
+}
 
 
 namespace arcticdb::storage::lmdb {

cpp/arcticdb/storage/lmdb/lmdb_mock_client.cpp

@@ -11,6 +11,7 @@
 #include <arcticdb/entity/atom_key.hpp>
 #include <arcticdb/entity/serialized_key.hpp>
 #include <arcticdb/util/string_utils.hpp>
+#include <arcticdb/storage/lmdb/lmdb.hpp>
 
 
 namespace arcticdb::storage::lmdb {

cpp/arcticdb/storage/lmdb/lmdb_real_client.cpp

@@ -11,7 +11,7 @@
 #include <arcticdb/entity/variant_key.hpp>
 #include <arcticdb/storage/lmdb/lmdb_real_client.hpp>
 #include <arcticdb/storage/storage_utils.hpp>
-
+#include <arcticdb/storage/lmdb/lmdb.hpp>
 
 namespace arcticdb::storage::lmdb {