#2487: CI: switch one build to use the C++20 standard

docker-bake.hcl

@@ -184,6 +184,11 @@ function "vt_ldms" {
   result = lookup(item, "vt_ldms", "")
 }
 
+function "vt_cmake_cxx_standard" {
+  params = [item]
+  result = lookup(item, "vt_cmake_cxx_standard", 17)
+}
+
 target "vt-build" {
   target = "build"
   context = "."
@@ -243,6 +248,7 @@ target "vt-build-all" {
     VT_UNITY_BUILD_ENABLED         = vt_unity_build(item)
     VT_WERROR_ENABLED              = vt_werror(item)
     VT_ZOLTAN_ENABLED              = vt_zoltan(item)
+    CMAKE_CXX_STANDARD             = vt_cmake_cxx_standard(item)
   }
 
   # to get the list of available images from DARMA-tasking/workflows:
@@ -332,6 +338,8 @@ target "vt-build-all" {
       },
       {
         image = "amd64-ubuntu-22.04-clang-15-cpp"
+        variant = "cxx20"
+        vt_cmake_cxx_standard = 20
       },
       {
         image = "amd64-ubuntu-22.04-gcc-11-cpp"

examples/collection/jacobi1d_vt.cc

@@ -128,7 +128,7 @@ struct LinearPb1DJacobi : vt::Collection<LinearPb1DJacobi,vt::Index1D> {
         "\n Maximum Number of Iterations Reached. \n\n" :
         fmt::format("\n Max-Norm Residual Reduced by {} \n\n", default_tol);
 
-      fmt::print(to_print);
+      fmt::print(fmt::runtime(to_print));
 
       // Notify all nodes that computation is finished
       objProxy_.broadcast<&NodeObj::workFinishedHandler>();

examples/collection/jacobi2d_vt.cc

@@ -139,7 +139,7 @@ struct LinearPb2DJacobi : vt::Collection<LinearPb2DJacobi,vt::Index2D> {
         "\n Maximum Number of Iterations Reached. \n\n" :
         fmt::format("\n Max-Norm Residual Reduced by {} \n\n", default_tol);
 
-      fmt::print(to_print);
+      fmt::print(fmt::runtime(to_print));
 
       // Notify all nodes that computation is finished
       objProxy_.broadcast<&NodeObj::workFinishedHandler>();

examples/collection/jacobi3d_vt.cc

@@ -135,7 +135,7 @@ struct LinearPb3DJacobi : vt::Collection<LinearPb3DJacobi,vt::Index3D> {
         "\n Maximum Number of Iterations Reached. \n\n" :
         fmt::format("\n Max-Norm Residual Reduced by {} \n\n", default_tol);
 
-      fmt::print(to_print);
+      fmt::print(fmt::runtime(to_print));
 
       // Notify all nodes that computation is finished
       objProxy_.broadcast<&NodeObj::workFinishedHandler>();

src/vt/collective/basic.cc

@@ -62,7 +62,7 @@ void output(
 #if !vt_check_enabled(trace_only)
   return CollectiveOps::output(str,code,error,decorate,formatted,abort_out);
 #else
-  ::fmt::print(str.c_str());
+  ::fmt::print("{}", str);
 #endif
 }
 

src/vt/collective/collective_ops.cc

@@ -347,7 +347,7 @@ void CollectiveAnyOps<instance>::output(
   if (myrt) {
     myrt->output(str,code,error,decorate,formatted);
   } else {
-    ::fmt::print(str.c_str());
+    ::fmt::print("{}", str);
   }
   if (error and abort_out) {
     vt::abort("Assertion Failed", 129);

src/vt/collective/reduce/reduce.impl.h

@@ -151,7 +151,7 @@ Reduce::PendingSendType Reduce::reduce(
   ReduceNumType num_contrib
 ) {
   auto msg_ptr = promoteMsg(msg);
-  return PendingSendType{theMsg()->getEpochContextMsg(msg_ptr), [=](){
+  return PendingSendType{theMsg()->getEpochContextMsg(msg_ptr), [this, root, msg_ptr, id, num_contrib](){
                            reduceImmediate<f>(root, msg_ptr.get(), id, num_contrib);
                          } };
 }

src/vt/elm/elm_id.h

@@ -85,7 +85,7 @@ struct ElementIDStruct {
 };
 
 inline auto format_as(ElementIDStruct e) {
-  auto fmt_str = "({},{},{},{})";
+  auto constexpr fmt_str = "({},{},{},{})";
   return fmt::format(
     fmt_str, e.id, e.getHomeNode(), e.curr_node, e.isMigratable()
   );

src/vt/messaging/active.cc

@@ -1107,7 +1107,7 @@ void ActiveMessenger::finishPendingActiveMsgAsyncRecv(InProgressIRecv* irecv) {
     } else {
       /*bool const put_delivered = */recvDataMsg(
         1, put_tag, sender,
-        [=](PtrLenPairType ptr, ActionType deleter){
+        [this, base, sender](PtrLenPairType ptr, ActionType deleter){
           envelopeSetPutPtr(base->env, std::get<0>(ptr), std::get<1>(ptr));
           processActiveMsg(base, sender, true, deleter);
         }

src/vt/messaging/collection_chain_set.impl.h

@@ -69,7 +69,7 @@ CollectionChainSet<Index>::CollectionChainSet(
   auto const this_node = theContext()->getNode();
   auto const proxy_bits = proxy.getProxy();
 
-  ListenerType l = [=](ElementEventEnum event, IndexT idx, NodeType home) {
+  ListenerType l = [this, p, layout, this_node](ElementEventEnum event, IndexT idx, NodeType home) {
     switch (event) {
     case ElementEventEnum::ElementCreated:
     case ElementEventEnum::ElementMigratedIn:

src/vt/rdma/rdma.cc

@@ -1289,7 +1289,7 @@ void RDMAManager::createDirectChannelInternal(
     );
 
     auto cb = theCB()->makeFunc<GetInfoChannel>(
-      pipe::LifetimeEnum::Once, [=](GetInfoChannel* msg){
+      pipe::LifetimeEnum::Once, [this, type, han, non_target, action, unique_channel_tag, is_target, override_target](GetInfoChannel* msg){
         auto const& my_num_bytes = msg->num_bytes;
         createDirectChannelFinish(
           type, han, non_target, action, unique_channel_tag, is_target, my_num_bytes,
@@ -1326,7 +1326,7 @@ void RDMAManager::removeDirectChannel(
   auto const target = getTarget(han, override_target);
 
   if (this_node != target) {
-    auto cb = theCB()->makeFunc(pipe::LifetimeEnum::Once, [=]{
+    auto cb = theCB()->makeFunc(pipe::LifetimeEnum::Once, [this, han, action, target, this_node]{
       auto iter = channels_.find(
         makeChannelLookup(han,RDMA_TypeType::Put,target,this_node)
       );

src/vt/rdmahandle/holder.impl.h

@@ -150,7 +150,7 @@ RequestHolder Holder<T,E>::rget(
   auto mpi_type_str = TypeMPI<T>::getTypeStr();
   RequestHolder r;
   if (mpi2_) {
-    r.add([=]{
+    r.add([this, l, node, ptr, offset, len, mpi_type, mpi_type_str]{
       LockMPI _scope_lock(l, node, data_window_);
       vt_debug_print(
         verbose, rdma,
@@ -188,7 +188,7 @@ RequestHolder Holder<T,E>::rput(
   auto mpi_type_str = TypeMPI<T>::getTypeStr();
   RequestHolder r;
   if (mpi2_) {
-    r.add([=]{
+    r.add([this, l, node, ptr, offset, len, mpi_type, mpi_type_str]{
       LockMPI _scope_lock(l, node, data_window_);
       vt_debug_print(
         verbose, rdma,
@@ -245,7 +245,7 @@ RequestHolder Holder<T,E>::raccum(
   auto mpi_type_str = TypeMPI<T>::getTypeStr();
   RequestHolder r;
   if (mpi2_) {
-    r.add([=]{
+    r.add([this, l, node, offset, ptr, len, mpi_type, mpi_type_str, op]{
       LockMPI _scope_lock(l, node, data_window_);
       vt_debug_print(
         verbose, rdma,

src/vt/runtime/component/diagnostic_value_format.h

@@ -158,7 +158,7 @@ struct DiagnosticFormatter {
 
       if (multiplier == 0) {
         return fmt::format(
-          default_spec + " {}", val, unitFormat(unit_name, align)
+          fmt::runtime(default_spec + " {}"), val, unitFormat(unit_name, align)
         );
       } else {
         // Compute the new value with multiplier as a double
@@ -169,7 +169,7 @@ struct DiagnosticFormatter {
 
         auto decimal = std::string{decimal_format};
         return fmt::format(
-          decimal + " {}", new_value, unitFormat(unit_name, align)
+          fmt::runtime(decimal + " {}"), new_value, unitFormat(unit_name, align)
         );
       }
       break;
@@ -206,7 +206,7 @@ struct DiagnosticFormatter {
 
       if (multiplier == 0) {
         return fmt::format(
-          default_spec + " {}", val, unitFormat(unit_name, align)
+          fmt::runtime(default_spec + " {}"), val, unitFormat(unit_name, align)
         );
       } else {
         // Compute the new value with multiplier as a double
@@ -217,7 +217,7 @@ struct DiagnosticFormatter {
 
         auto decimal = std::string{decimal_format};
         return fmt::format(
-          decimal + " {}", new_value, unitFormat(unit_name, align)
+          fmt::runtime(decimal + " {}"), new_value, unitFormat(unit_name, align)
         );
       }
 
@@ -255,7 +255,7 @@ struct DiagnosticFormatter {
 
       if (multiplier == 0) {
         return fmt::format(
-          default_spec + " {}", val, unitFormat(unit_name, align)
+          fmt::runtime(default_spec + " {}"), val, unitFormat(unit_name, align)
         );
       } else {
         // Compute the new value with multiplier as a double
@@ -264,15 +264,15 @@ struct DiagnosticFormatter {
 
         auto decimal = std::string{decimal_format};
         return fmt::format(
-          decimal + " {}", new_value, unitFormat(unit_name, align)
+          fmt::runtime(decimal + " {}"), new_value, unitFormat(unit_name, align)
         );
       }
 
       break;
     }
     case DiagnosticUnit::UnitsPerSecond:
     default:
-      return fmt::format(default_spec, val);
+      return fmt::format(fmt::runtime(default_spec), val);
       break;
     }
     return "";

src/vt/runtime/runtime_banner.cc

@@ -292,7 +292,7 @@ void Runtime::printStartupBanner() {
       if (getAppConfig()->vt_lb_show_config) {
         auto s = opt_on("--vt_lb_show_config", "Showing LB specification");
         fmt::print("{}\t{}", vt_pre, s);
-        fmt::print(vrt::collection::balance::ReadLBConfig::toString());
+        fmt::print("{}", vrt::collection::balance::ReadLBConfig::toString());
       }
     } else {
       auto a3 = fmt::format("Load balancer name: \"{}\"", getAppConfig()->vt_lb_name);
@@ -950,7 +950,7 @@ void Runtime::printStartupBanner() {
   }
 
   //fmt::print("{}\n", reset);
-  fmt::print(reset);
+  fmt::print("{}", reset);
 
   // Enqueue a check for later in case arguments are modified before work
   // actually executes

src/vt/runtime/runtime_diagnostics.cc

@@ -83,13 +83,13 @@ struct FormatHelper {
     using DF = component::detail::DiagnosticFormatter;
     using component::detail::decimal_format;
 
-    bool const is_decimal =
+    constexpr bool is_decimal =
       std::is_same<T, float>::value or std::is_same<T, double>::value;
 
-    std::string default_format = is_decimal ? decimal_format : std::string{"{}"};
+    std::string default_format = is_decimal ? decimal_format : "{}";
 
     if (base_) {
-      return fmt::format(default_format, std::get<T>(eval));
+      return fmt::format(fmt::runtime(default_format), std::get<T>(eval));
     } else {
       return DF::getValueWithUnits(std::get<T>(eval), unit_, default_format, align_);
     }
@@ -299,9 +299,8 @@ void Runtime::computeAndPrintDiagnostics() {
     );
 
     auto out = fmt::format("{}", table.to_string());
-
     if (theConfig()->vt_diag_print_summary) {
-      fmt::print(out);
+      fmt::print("{}", out);
     }
 
     if (theConfig()->vt_diag_summary_file != "") {

src/vt/topos/location/location.impl.h

@@ -597,7 +597,7 @@ void EntityLocationCoord<EntityID>::routeMsgNode(
 
     theTerm()->produce(epoch);
 
-    auto trigger_msg_handler_action = [=](EntityID const& hid) {
+    auto trigger_msg_handler_action = [this, msg, home_node](EntityID const& hid) {
       bool const& has_handler = msg->hasHandler();
       auto const& from = msg->getLocFromNode();
       if (has_handler) {
@@ -662,7 +662,7 @@ void EntityLocationCoord<EntityID>::routeMsgNode(
 
       EntityID id_ = id;
       // buffer the message here, the entity will be registered in the future
-      insertPendingEntityAction(id_, [=](NodeType resolved) {
+      insertPendingEntityAction(id_, [this, id_, epoch, msg, home_node, trigger_msg_handler_action](NodeType resolved) {
         auto const& my_node = theContext()->getNode();
 
         vt_debug_print(
@@ -779,7 +779,7 @@ void EntityLocationCoord<EntityID>::routePreparedMsg(
   } else {
     theTerm()->produce(epoch);
     // non-eager protocol: get location first then send message after resolution
-    getLocation(msg->getEntity(), msg->getHomeNode(), [=](NodeType node) {
+    getLocation(msg->getEntity(), msg->getHomeNode(), [this, epoch, msg](NodeType node){
       theMsg()->pushEpoch(epoch);
       routeMsgNode<MessageT>(
         msg->getEntity(), msg->getHomeNode(), node, msg

src/vt/vrt/collection/balance/lb_common.h

@@ -77,6 +77,10 @@ static constexpr ElementIDType const no_element_id = elm::no_element_id;
 struct PhaseOffset {
   PhaseOffset() = delete;
 
+  PhaseOffset(int in_phases, unsigned int in_subphase)
+    : phases(in_phases), subphase(in_subphase)
+  {}
+
   int phases;
   static constexpr unsigned int NEXT_PHASE = 0;
 

src/vt/vrt/collection/balance/lb_invoke/lb_manager.cc

@@ -186,7 +186,7 @@ void LBManager::defaultPostLBWork(ReassignmentMsg* msg) {
   auto phase = msg->phase;
   auto proposed = std::make_shared<ProposedReassignment>(model_, reassignment);
 
-  runInEpochCollective("LBManager::runLB -> computeStats", [=] {
+  runInEpochCollective("LBManager::runLB -> computeStats", [this, proposed, phase] {
     auto stats_cb = vt::theCB()->makeBcast<&LBManager::statsHandler>(proxy_);
     before_lb_stats_ = false;
     computeStatistics(proposed, false, phase, stats_cb);
@@ -228,7 +228,7 @@ void LBManager::defaultPostLBWork(ReassignmentMsg* msg) {
 
 void
 LBManager::runLB(PhaseType phase, vt::Callback<ReassignmentMsg> cb) {
-  runInEpochCollective("LBManager::runLB -> updateLoads", [=] {
+  runInEpochCollective("LBManager::runLB -> updateLoads", [this, phase] {
     model_->updateLoads(phase);
   });
 
@@ -241,7 +241,7 @@ LBManager::runLB(PhaseType phase, vt::Callback<ReassignmentMsg> cb) {
     );
   }
 
-  runInEpochCollective("LBManager::runLB -> computeStats", [=] {
+  runInEpochCollective("LBManager::runLB -> computeStats", [this, phase] {
     auto stats_cb = vt::theCB()->makeBcast<&LBManager::statsHandler>(proxy_);
     before_lb_stats_ = true;
     computeStatistics(model_, false, phase, stats_cb);
@@ -327,11 +327,11 @@ void LBManager::startLB(
     last_phase_info_->migration_count = 0;
     last_phase_info_->ran_lb = false;
 
-    runInEpochCollective("LBManager::noLB -> updateLoads", [=] {
+    runInEpochCollective("LBManager::noLB -> updateLoads", [this, phase] {
       model_->updateLoads(phase);
     });
 
-    runInEpochCollective("LBManager::noLB -> computeStats", [=] {
+    runInEpochCollective("LBManager::noLB -> computeStats", [this, phase] {
       before_lb_stats_ = true;
       auto stats_cb = vt::theCB()->makeBcast<&LBManager::statsHandler>(proxy_);
       before_lb_stats_ = true;
@@ -372,13 +372,13 @@ void LBManager::startLB(
 /*static*/
 void LBManager::printLBArgsHelp(LBType lb) {
   auto sep = fmt::format("{}{:-^120}{}\n", debug::bd_green(), "", debug::reset());
-  fmt::print(sep);
+  fmt::print("{}", sep);
   fmt::print(
     "{}{}LB arguments for {}{}{}:\n",
     debug::vtPre(), debug::green(), debug::magenta(),
     get_lb_names()[lb], debug::reset()
   );
-  fmt::print(sep);
+  fmt::print("{}", sep);
   fmt::print("\n");
 
   std::unordered_map<std::string, std::string> help;

src/vt/vrt/collection/balance/temperedlb/tempered_msgs.h

@@ -132,7 +132,7 @@ using ClusterSummaryType = std::unordered_map<SharedIDType, ClusterInfo>;
 using RankSummaryType = std::tuple<BytesType, ClusterSummaryType>;
 
 inline auto format_as(ClusterInfo const& e) {
-  auto fmt_str = "(load={},bytes={},intra=({},{})),home={},edge={}";
+  auto constexpr fmt_str = "(load={},bytes={},intra=({},{})),home={},edge={}";
   return fmt::format(
     fmt_str, e.load, e.bytes, e.intra_send_vol, e.intra_recv_vol,
     e.home_node, e.edge_weight

src/vt/vrt/collection/manager.impl.h

@@ -127,7 +127,7 @@ CollectionManager::runConstructor(Args&&... args) {
 
 template <typename ColT>
 void CollectionManager::addCleanupFn(VirtualProxyType proxy) {
-  cleanup_fns_[proxy].push_back([=]{
+  cleanup_fns_[proxy].push_back([this, proxy]{
     CollectionProxyWrapType<ColT> typed_proxy(proxy);
     destroyMatching(typed_proxy);
   });
@@ -1792,7 +1792,7 @@ MigrateStatus CollectionManager::migrate(
 
   auto const epoch = theMsg()->getEpoch();
   theTerm()->produce(epoch);
-  schedule([=]{
+  schedule([this, epoch, col_proxy, idx, dest]{
     theMsg()->pushEpoch(epoch);
     migrateOut<ColT,IndexT>(col_proxy, idx, dest);
     theMsg()->popEpoch(epoch);
@@ -2342,7 +2342,7 @@ messaging::PendingSend CollectionManager::schedule(
 ) {
   theTerm()->produce(cur_epoch);
   return messaging::PendingSend(
-    msg, [=]([[maybe_unused]] MsgVirtualPtr<BaseMsgType> inner_msg
+    msg, [this, cur_epoch, action, execute_now]([[maybe_unused]] MsgVirtualPtr<BaseMsgType> inner_msg
   ){
     auto fn = [=]{
       theMsg()->pushEpoch(cur_epoch);