diff --git a/flang/lib/Semantics/check-declarations.cpp b/flang/lib/Semantics/check-declarations.cpp
--- a/flang/lib/Semantics/check-declarations.cpp
+++ b/flang/lib/Semantics/check-declarations.cpp
@@ -1565,6 +1565,12 @@
         msg =
             "In defined assignment subroutine '%s', second dummy"
             " argument '%s' must have INTENT(IN) or VALUE attribute"_err_en_US;
+      } else if (dataObject->attrs.test(DummyDataObject::Attr::Pointer)) {
+        msg =
+            "In defined assignment subroutine '%s', second dummy argument '%s' must not be a pointer"_err_en_US;
+      } else if (dataObject->attrs.test(DummyDataObject::Attr::Allocatable)) {
+        msg =
+            "In defined assignment subroutine '%s', second dummy argument '%s' must not be an allocatable"_err_en_US;
       }
     } else {
       DIE("pos must be 0 or 1");
diff --git a/flang/test/Semantics/resolve65.f90 b/flang/test/Semantics/resolve65.f90
--- a/flang/test/Semantics/resolve65.f90
+++ b/flang/test/Semantics/resolve65.f90
@@ -65,6 +65,18 @@
         end
       end interface
     end
+    !ERROR: In defined assignment subroutine 's3', second dummy argument 'y' must not be a pointer
+    subroutine s3(x, y)
+      import t
+      type(t), intent(out) :: x
+      type(t), intent(in), pointer :: y
+    end
+    !ERROR: In defined assignment subroutine 's4', second dummy argument 'y' must not be an allocatable
+    subroutine s4(x, y)
+      import t
+      type(t), intent(out) :: x
+      type(t), intent(in), allocatable :: y
+    end
   end interface
 end