1 files changed, 71 insertions, 0 deletions
diff --git a/flang/lib/Semantics/check-coarray.cpp b/flang/lib/Semantics/check-coarray.cpp
index f291a80a7033..688c3a7c92ad 100644
--- a/flang/lib/Semantics/check-coarray.cpp
+++ b/flang/lib/Semantics/check-coarray.cpp
@@ -124,6 +124,19 @@ static void CheckSyncStatList(
   }
 }
 
+static void CheckEventVariable(
+    SemanticsContext &context, const parser::EventVariable &eventVar) {
+  if (const auto *expr{GetExpr(context, eventVar)}) {
+    if (!IsEventType(evaluate::GetDerivedTypeSpec(expr->GetType()))) { // C1176
+      context.Say(parser::FindSourceLocation(eventVar),
+          "The event-variable must be of type EVENT_TYPE from module ISO_FORTRAN_ENV"_err_en_US);
+    } else if (!evaluate::IsCoarray(*expr)) { // C1604
+      context.Say(parser::FindSourceLocation(eventVar),
+          "The event-variable must be a coarray"_err_en_US);
+    }
+  }
+}
+
 void CoarrayChecker::Leave(const parser::ChangeTeamStmt &x) {
   CheckNamesAreDistinct(std::get<std::list<parser::CoarrayAssociation>>(x.t));
   CheckTeamType(context_, std::get<parser::TeamValue>(x.t));
@@ -156,6 +169,64 @@ void CoarrayChecker::Leave(const parser::SyncTeamStmt &x) {
   CheckSyncStatList(context_, std::get<std::list<parser::StatOrErrmsg>>(x.t));
 }
 
+void CoarrayChecker::Leave(const parser::EventPostStmt &x) {
+  CheckSyncStatList(context_, std::get<std::list<parser::StatOrErrmsg>>(x.t));
+  CheckEventVariable(context_, std::get<parser::EventVariable>(x.t));
+}
+
+void CoarrayChecker::Leave(const parser::EventWaitStmt &x) {
+  const auto &eventVar{std::get<parser::EventVariable>(x.t)};
+
+  if (const auto *expr{GetExpr(context_, eventVar)}) {
+    if (ExtractCoarrayRef(expr)) {
+      context_.Say(parser::FindSourceLocation(eventVar), // C1177
+          "A event-variable in a EVENT WAIT statement may not be a coindexed object"_err_en_US);
+    } else {
+      CheckEventVariable(context_, eventVar);
+    }
+  }
+
+  bool gotStat{false}, gotMsg{false}, gotUntil{false};
+  using EventWaitSpec = parser::EventWaitStmt::EventWaitSpec;
+  for (const EventWaitSpec &eventWaitSpec :
+      std::get<std::list<EventWaitSpec>>(x.t)) {
+    common::visit(
+        common::visitors{
+            [&](const parser::ScalarIntExpr &untilCount) {
+              if (gotUntil) {
+                context_.Say( // C1178
+                    "Until-spec in a event-wait-spec-list may not be repeated"_err_en_US);
+              }
+              gotUntil = true;
+            },
+            [&](const parser::StatOrErrmsg &statOrErrmsg) {
+              common::visit(
+                  common::visitors{
+                      [&](const parser::StatVariable &stat) {
+                        if (gotStat) {
+                          context_.Say( // C1178
+                              "A stat-variable in a event-wait-spec-list may not be repeated"_err_en_US);
+                        }
+                        gotStat = true;
+                      },
+                      [&](const parser::MsgVariable &errmsg) {
+                        if (gotMsg) {
+                          context_.Say( // C1178
+                              "A errmsg-variable in a event-wait-spec-list may not be repeated"_err_en_US);
+                        }
+                        gotMsg = true;
+                      },
+                  },
+                  statOrErrmsg.u);
+              CheckCoindexedStatOrErrmsg(
+                  context_, statOrErrmsg, "event-wait-spec-list");
+            },
+
+        },
+        eventWaitSpec.u);
+  }
+}
+
 void CoarrayChecker::Leave(const parser::ImageSelector &imageSelector) {
   haveStat_ = false;
   haveTeam_ = false;