Fix inquiry behaviour for is_read

src/psyclone/psyir/nodes/reference.py

@@ -102,10 +102,17 @@ def is_read(self):
         '''
         # pylint: disable=import-outside-toplevel
         from psyclone.psyir.nodes.assignment import Assignment
+        from psyclone.psyir.nodes.intrinsic_call import IntrinsicCall
         parent = self.parent
         if isinstance(parent, Assignment):
             if parent.lhs is self:
                 return False
+
+        # If we have an intrinsic call parent then we need to check if its
+        # an inquiry. Inquiry functions don't read from their arguments.
+        if isinstance(parent, IntrinsicCall) and parent.is_inquiry:
+            return False
+
         # All references other than LHS of assignments represent a read. This
         # can be improved in the future by looking at Call intents.
         return True

src/psyclone/tests/psyir/nodes/reference_test.py

@@ -583,6 +583,7 @@ def test_reference_is_read(fortran_reader):
     code = """subroutine my_subroutine()
         b = a
         call somecall(c)
+        b = lbound(d)
     end subroutine"""
 
     psyir = fortran_reader.psyir_from_source(code)
@@ -591,6 +592,8 @@ def test_reference_is_read(fortran_reader):
     assert references[1].is_read
     assert references[3].symbol.name == "c"
     assert references[3].is_read
+    assert references[6].symbol.name == "d"
+    assert not references[6].is_read
 
 
 def test_reference_is_write(fortran_reader):