[flang] Enforce C1027 (F'2023) (#129617)

The LHS of a pointer assignment statement may not be coindexed.

1 files changed, 4 insertions, 1 deletions

diff --git a/flang/lib/Semantics/pointer-assignment.cpp b/flang/lib/Semantics/pointer-assignment.cpp
index 654c018..23a64d0 100644
--- a/flang/lib/Semantics/pointer-assignment.cpp
+++ b/flang/lib/Semantics/pointer-assignment.cpp
@@ -154,6 +154,9 @@ bool PointerAssignmentChecker::CheckLeftHandSide(const SomeExpr &lhs) {
   } else if (evaluate::IsAssumedRank(lhs)) {
     Say("The left-hand side of a pointer assignment must not be an assumed-rank dummy argument"_err_en_US);
     return false;
+  } else if (evaluate::ExtractCoarrayRef(lhs)) { // F'2023 C1027
+    Say("The left-hand side of a pointer assignment must not be coindexed"_err_en_US);
+    return false;
   } else {
     return true;
   }
@@ -177,7 +180,7 @@ bool PointerAssignmentChecker::Check(const SomeExpr &rhs) {
     Say("An array section with a vector subscript may not be a pointer target"_err_en_US);
     return false;
   }
-  if (ExtractCoarrayRef(rhs)) { // C1026
+  if (ExtractCoarrayRef(rhs)) { // F'2023 C1029
     Say("A coindexed object may not be a pointer target"_err_en_US);
     return false;
   }