Filling of symbol->scope annotation moved from narrow to fill_candidate_datatypes_c (became possible because narrowing of struct, array and symbolic variables is now done directly in fill_candidate_datatypes_c)
Things that we must still check for in stage 3:
1) Handling of CONSTANTs:
1.a) "Any program organization unit attempts to modify the value of a variable that has been declared with the CONSTANT qualifier;"
1.b) From table 16.a "The CONSTANT qualifier shall not be used in the declaration of function block instances as described in 2.5.2.1."