RoadMap2008

VHDL 2008 new features

This is a list of features added in VHDL 2008 and not yet implemented in GHDL. It may be not complete.

1. Overview
   • PSL
2. References
3. Design entities and config
   • generate_specification (alternative label)
4. Subprogram and packages
   • subprogram_header, parameter
   • subprogram instantiation
   • package header [Partial]
   • package instantiation [Partial]
5. Types
   • unconstrained subtype
   • minimum, maximum, to_string for scalar types [Done]
   • predefined array types [Done]
   • minimum, maximum, to_string for array types [Done]
   • flush for file type [Done]
6. Declarations
   • subtype indication
   • variables (declared in instantiated packages)
   • interface_type_declaration
   • interface_subprogram_declaration
   • interface_package_declaration
   • anonymous signal in port clause
   • alias (rules have changed) [Done]
7. Specifications
   • compound_configuration_specification
   • disconnection_specification (changes)
8. Names
   • External names
9. Expressions
   • condition operator [Done]
   • unary logical operators [Done]
   • matching relational operators [Done]
   • mod/rem for physical types
   • array aggregates (changes)
   • type conversions (changes)
   • static expressions
10. Sequential statements
    • assertions (minor changes)
    • force/release
    • conditional signal assignments
    • selected signal assignments
    • conditional variable assignment
    • selected variable assignment
    • matching case statement
11. Concurrent statements
    • concurrent signal assignment (changes)
    • if_generate_statement (elsif/else)
    • case_generate_statement
12. Scope and visibility
    • alias (changes) [Done]
    • use (explicit) [Done]
13. Design units
    • context_declaration [Done]
    • context clauses [Done]
14. Elaboration
    • vhpi
    • changes
15. Lexical elements
    • new tokens and reserved words
    • tool directive
    • bit string literals [Done]
    • delimited comments [Done]
16. Predefined language environment
    • 'Subtype
    • 'Element
    • 'Simple_Name, 'Path_Name and 'Instance_Name
    • std.standard: riging_edge, falling_edge, ??, NOW impure, To_*String
    • std.textio: justify, sread, oread, hread, tree, write (with format), swrite,
      bwrite, owrite, hwrite. Handling of LF.
    • std.env package
    • add ieee packages