Revert "[flang] Add check for constraints on event-stmts"

This reverts commit 9725c740fbe7841a7aed57ca35f83d28aac1814c.

9 files changed, 22 insertions, 181 deletions

diff --git a/flang/include/flang/Evaluate/tools.h b/flang/include/flang/Evaluate/tools.h
index 716c4a972694..dfc811fa2856 100644
--- a/flang/include/flang/Evaluate/tools.h
+++ b/flang/include/flang/Evaluate/tools.h
@@ -1201,8 +1201,6 @@ bool IsLenTypeParameter(const Symbol &);
 bool IsExtensibleType(const DerivedTypeSpec *);
 bool IsBuiltinDerivedType(const DerivedTypeSpec *derived, const char *name);
 bool IsBuiltinCPtr(const Symbol &);
-bool IsEventType(const DerivedTypeSpec *);
-bool IsLockType(const DerivedTypeSpec *);
 // Is this derived type TEAM_TYPE from module ISO_FORTRAN_ENV?
 bool IsTeamType(const DerivedTypeSpec *);
 // Is this derived type TEAM_TYPE, C_PTR, or C_FUNPTR?
diff --git a/flang/lib/Evaluate/tools.cpp b/flang/lib/Evaluate/tools.cpp
index befe28605055..b9fb511b47cb 100644
--- a/flang/lib/Evaluate/tools.cpp
+++ b/flang/lib/Evaluate/tools.cpp
@@ -1568,14 +1568,6 @@ bool IsIsoCType(const DerivedTypeSpec *derived) {
       IsBuiltinDerivedType(derived, "c_funptr");
 }
 
-bool IsEventType(const DerivedTypeSpec *derived) {
-  return IsBuiltinDerivedType(derived, "event_type");
-}
-
-bool IsLockType(const DerivedTypeSpec *derived) {
-  return IsBuiltinDerivedType(derived, "lock_type");
-}
-
 bool IsTeamType(const DerivedTypeSpec *derived) {
   return IsBuiltinDerivedType(derived, "team_type");
 }
@@ -1585,7 +1577,8 @@ bool IsBadCoarrayType(const DerivedTypeSpec *derived) {
 }
 
 bool IsEventTypeOrLockType(const DerivedTypeSpec *derivedTypeSpec) {
-  return IsEventType(derivedTypeSpec) || IsLockType(derivedTypeSpec);
+  return IsBuiltinDerivedType(derivedTypeSpec, "event_type") ||
+      IsBuiltinDerivedType(derivedTypeSpec, "lock_type");
 }
 
 int CountLenParameters(const DerivedTypeSpec &type) {
diff --git a/flang/lib/Semantics/check-coarray.cpp b/flang/lib/Semantics/check-coarray.cpp
index 688c3a7c92ad..f291a80a7033 100644
--- a/flang/lib/Semantics/check-coarray.cpp
+++ b/flang/lib/Semantics/check-coarray.cpp
@@ -124,19 +124,6 @@ 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));
@@ -169,64 +156,6 @@ 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;
diff --git a/flang/lib/Semantics/check-coarray.h b/flang/lib/Semantics/check-coarray.h
index 51d030cbf771..b4ce5b42ad6f 100644
--- a/flang/lib/Semantics/check-coarray.h
+++ b/flang/lib/Semantics/check-coarray.h
@@ -17,8 +17,6 @@ class CharBlock;
 class MessageFixedText;
 struct ChangeTeamStmt;
 struct CoarrayAssociation;
-struct EventPostStmt;
-struct EventWaitStmt;
 struct FormTeamStmt;
 struct ImageSelector;
 struct SyncAllStmt;
@@ -37,8 +35,6 @@ public:
   void Leave(const parser::SyncImagesStmt &);
   void Leave(const parser::SyncMemoryStmt &);
   void Leave(const parser::SyncTeamStmt &);
-  void Leave(const parser::EventPostStmt &);
-  void Leave(const parser::EventWaitStmt &);
   void Leave(const parser::ImageSelector &);
   void Leave(const parser::FormTeamStmt &);
 
diff --git a/flang/test/Lower/pre-fir-tree04.f90 b/flang/test/Lower/pre-fir-tree04.f90
index e5f804245854..8188bfd54b40 100644
--- a/flang/test/Lower/pre-fir-tree04.f90
+++ b/flang/test/Lower/pre-fir-tree04.f90
@@ -6,8 +6,8 @@
 Subroutine test_coarray
   use iso_fortran_env, only: team_type, event_type, lock_type
   type(team_type) :: t
-  type(event_type) :: done[*]
-  type(lock_type) :: alock[*]
+  type(event_type) :: done
+  type(lock_type) :: alock
   real :: y[10,*]
   integer :: counter[*]
   logical :: is_square
diff --git a/flang/test/Semantics/critical02.f90 b/flang/test/Semantics/critical02.f90
index e1c9bb3e0ff1..10581f9fd805 100644
--- a/flang/test/Semantics/critical02.f90
+++ b/flang/test/Semantics/critical02.f90
@@ -61,7 +61,7 @@ end subroutine test6
 
 subroutine test7()
   use iso_fortran_env
-  type(event_type) :: x[*], y[*]
+  type(event_type) :: x, y
   critical
     !ERROR: An image control statement is not allowed in a CRITICAL construct
     event post (x)
diff --git a/flang/test/Semantics/doconcurrent01.f90 b/flang/test/Semantics/doconcurrent01.f90
index 36595df5a62f..0f4e13da2290 100644
--- a/flang/test/Semantics/doconcurrent01.f90
+++ b/flang/test/Semantics/doconcurrent01.f90
@@ -66,7 +66,7 @@ end subroutine do_concurrent_test2
 
 subroutine s1()
   use iso_fortran_env
-  type(event_type) :: x[*]
+  type(event_type) :: x
   do concurrent (i = 1:n)
 !ERROR: An image control statement is not allowed in DO CONCURRENT
     event post (x)
@@ -75,7 +75,7 @@ end subroutine s1
 
 subroutine s2()
   use iso_fortran_env
-  type(event_type) :: x[*]
+  type(event_type) :: x
   do concurrent (i = 1:n)
 !ERROR: An image control statement is not allowed in DO CONCURRENT
     event wait (x)
diff --git a/flang/test/Semantics/event01b.f90 b/flang/test/Semantics/event01b.f90
index 6a207427f6d4..7cf374fbcc84 100644
--- a/flang/test/Semantics/event01b.f90
+++ b/flang/test/Semantics/event01b.f90
@@ -22,11 +22,9 @@ program test_event_post
   !______ invalid event-variable ____________________________
 
   ! event-variable must be event_type
-  !ERROR: The event-variable must be of type EVENT_TYPE from module ISO_FORTRAN_ENV
   event post(non_event)
 
   ! event-variable must be a coarray
-  !ERROR: The event-variable must be a coarray
   event post(non_coarray)
 
   !ERROR: Must be a scalar value, but is a rank-1 array
@@ -50,50 +48,18 @@ program test_event_post
 
   !______ invalid sync-stat-lists: redundant sync-stat-list ____________
 
-  !ERROR: The stat-variable in a sync-stat-list may not be repeated
+  ! No specifier shall appear more than once in a given sync-stat-list
   event post(concert, stat=sync_status, stat=superfluous_stat)
 
-  !ERROR: The stat-variable in a sync-stat-list may not be repeated
-  event post(concert, errmsg=error_message, stat=sync_status, stat=superfluous_stat)
-
-  !ERROR: The stat-variable in a sync-stat-list may not be repeated
-  event post(concert, stat=sync_status, errmsg=error_message, stat=superfluous_stat)
-
-  !ERROR: The stat-variable in a sync-stat-list may not be repeated
-  event post(concert, stat=sync_status, stat=superfluous_stat, errmsg=error_message)
-
-  !ERROR: The errmsg-variable in a sync-stat-list may not be repeated
+  ! No specifier shall appear more than once in a given sync-stat-list
   event post(concert, errmsg=error_message, errmsg=superfluous_errmsg)
 
-  !ERROR: The errmsg-variable in a sync-stat-list may not be repeated
-  event post(concert, stat=sync_status, errmsg=error_message, errmsg=superfluous_errmsg)
-
-  !ERROR: The errmsg-variable in a sync-stat-list may not be repeated
-  event post(concert, errmsg=error_message, stat=sync_status, errmsg=superfluous_errmsg)
-
-  !ERROR: The errmsg-variable in a sync-stat-list may not be repeated
-  event post(concert, errmsg=error_message, errmsg=superfluous_errmsg, stat=sync_status)
+  !______ invalid sync-stat-lists: coindexed stat-variable ____________
 
-  !______ invalid sync-stat-lists: coindexed stat-variable - C1173____________
-
-  !ERROR: The stat-variable or errmsg-variable in a sync-stat-list may not be a coindexed object
+  ! Check constraint C1173 from the Fortran 2018 standard
   event post(concert, stat=co_indexed_integer[1])
 
-  !ERROR: The stat-variable or errmsg-variable in a sync-stat-list may not be a coindexed object
+  ! Check constraint C1173 from the Fortran 2018 standard
   event post(concert, errmsg=co_indexed_character[1])
 
-  !ERROR: The stat-variable or errmsg-variable in a sync-stat-list may not be a coindexed object
-  event post(concert, stat=co_indexed_integer[1], errmsg=error_message)
-
-  !ERROR: The stat-variable or errmsg-variable in a sync-stat-list may not be a coindexed object
-  event post(concert, stat=sync_status, errmsg=co_indexed_character[1])
-
-  !ERROR: The stat-variable or errmsg-variable in a sync-stat-list may not be a coindexed object
-  !ERROR: The stat-variable or errmsg-variable in a sync-stat-list may not be a coindexed object
-  event post(concert, stat=co_indexed_integer[1], errmsg=co_indexed_character[1])
-
-  !ERROR: The stat-variable or errmsg-variable in a sync-stat-list may not be a coindexed object
-  !ERROR: The stat-variable or errmsg-variable in a sync-stat-list may not be a coindexed object
-  event post(concert, errmsg=co_indexed_character[1], stat=co_indexed_integer[1])
-
 end program test_event_post
diff --git a/flang/test/Semantics/event02b.f90 b/flang/test/Semantics/event02b.f90
index 20ee4047a1fe..8aa53bd96213 100644
--- a/flang/test/Semantics/event02b.f90
+++ b/flang/test/Semantics/event02b.f90
@@ -21,16 +21,16 @@ program test_event_wait
 
   !_________________________ invalid event-variable ________________________________
 
-  !ERROR: The event-variable must be of type EVENT_TYPE from module ISO_FORTRAN_ENV
+  ! event-variable must be event_type
   event wait(non_event)
 
-  !ERROR: The event-variable must be a coarray
+  ! event-variable must be a coarray
   event wait(non_coarray)
 
-  !ERROR: A event-variable in a EVENT WAIT statement may not be a coindexed object
+  ! event-variable must not be coindexed
   event wait(concert[1])
 
-  !ERROR: A event-variable in a EVENT WAIT statement may not be a coindexed object
+  ! event-variable must not be coindexed
   event wait(occurrences(1)[1])
 
   !ERROR: Must be a scalar value, but is a rank-1 array
@@ -62,62 +62,21 @@ program test_event_wait
 
   !______ invalid event-wait-spec-lists: redundant event-wait-spec-list ____________
 
-  !ERROR: Until-spec in a event-wait-spec-list may not be repeated
+  ! No specifier shall appear more than once in a given event-wait-spec-list
   event wait(concert, until_count=threshold, until_count=indexed(1))
 
-  !ERROR: Until-spec in a event-wait-spec-list may not be repeated
-  event wait(concert, until_count=threshold, stat=sync_status, until_count=indexed(1))
-
-  !ERROR: Until-spec in a event-wait-spec-list may not be repeated
-  event wait(concert, until_count=threshold, errmsg=error_message, until_count=indexed(1))
-
-  !ERROR: Until-spec in a event-wait-spec-list may not be repeated
-  event wait(concert, until_count=threshold, stat=sync_status, errmsg=error_message, until_count=indexed(1))
-
-  !ERROR: A stat-variable in a event-wait-spec-list may not be repeated
+  ! No specifier shall appear more than once in a given event-wait-spec-list
   event wait(concert, stat=sync_status, stat=superfluous_stat)
 
-  !ERROR: A stat-variable in a event-wait-spec-list may not be repeated
-  event wait(concert, stat=sync_status, until_count=threshold, stat=superfluous_stat)
-
-  !ERROR: A stat-variable in a event-wait-spec-list may not be repeated
-  event wait(concert, stat=sync_status, errmsg=error_message, stat=superfluous_stat)
-
-  !ERROR: A stat-variable in a event-wait-spec-list may not be repeated
-  event wait(concert, stat=sync_status, until_count=threshold, errmsg=error_message, stat=superfluous_stat)
-
-  !ERROR: A errmsg-variable in a event-wait-spec-list may not be repeated
+  ! No specifier shall appear more than once in a given event-wait-spec-list
   event wait(concert, errmsg=error_message, errmsg=superfluous_errmsg)
 
-  !ERROR: A errmsg-variable in a event-wait-spec-list may not be repeated
-  event wait(concert, errmsg=error_message, until_count=threshold, errmsg=superfluous_errmsg)
-
-  !ERROR: A errmsg-variable in a event-wait-spec-list may not be repeated
-  event wait(concert, errmsg=error_message, stat=superfluous_stat, errmsg=superfluous_errmsg)
+  !_____________ invalid sync-stat-lists: coindexed stat-variable __________________
 
-  !ERROR: A errmsg-variable in a event-wait-spec-list may not be repeated
-  event wait(concert, errmsg=error_message, until_count=threshold, stat=superfluous_stat, errmsg=superfluous_errmsg)
-
-  !_____________ invalid sync-stat-lists: coindexed stat-variable - C1173 __________________
-
-  !ERROR: The stat-variable or errmsg-variable in a event-wait-spec-list may not be a coindexed object
+  ! Check constraint C1173 from the Fortran 2018 standard
   event wait(concert, stat=co_indexed_integer[1])
 
-  !ERROR: The stat-variable or errmsg-variable in a event-wait-spec-list may not be a coindexed object
+  ! Check constraint C1173 from the Fortran 2018 standard
   event wait(concert, errmsg=co_indexed_character[1])
 
-  !ERROR: The stat-variable or errmsg-variable in a event-wait-spec-list may not be a coindexed object
-  event wait(concert, stat=co_indexed_integer[1], errmsg=error_message)
-
-  !ERROR: The stat-variable or errmsg-variable in a event-wait-spec-list may not be a coindexed object
-  event wait(concert, stat=sync_status, errmsg=co_indexed_character[1])
-
-  !ERROR: The stat-variable or errmsg-variable in a event-wait-spec-list may not be a coindexed object
-  !ERROR: The stat-variable or errmsg-variable in a event-wait-spec-list may not be a coindexed object
-  event wait(concert, stat=co_indexed_integer[1], errmsg=co_indexed_character[1])
-
-  !ERROR: The stat-variable or errmsg-variable in a event-wait-spec-list may not be a coindexed object
-  !ERROR: The stat-variable or errmsg-variable in a event-wait-spec-list may not be a coindexed object
-  event wait(concert, errmsg=co_indexed_character[1], stat=co_indexed_integer[1])
-
 end program test_event_wait