VHDL Issue Number: 0016 Classification: Language Definition Problem Language Version: VHDL-87 Summary: It is unclear what subtype checks are involved in a procedure call. Related Issues: Relevant LRM Sections: 8.5 Key Words and Phrases: Subprograms, parameters, subtype checks Current Status: Submitted 1076-1993 Disposition: Closed (All Issues Completely Addressed) Disposition Rationale: Issues addressed in VHDL 93 LRM Superseded By: N/A ----------------------- Date Submitted: 1989/02/10 Author of Submission: Doug Dunlop Author's Affiliation: Intermetrics, Inc. Author's Post Address: 4733 Bethesda Ave #415 Bethesda, MD 20814 Author's Phone Number: (301) 657-3775 Author's Fax Number: Author's Net Address: dunlop@inmet.inmet.com ----------------------- Date Analyzed: TBD Author of Analysis: TBD Revision Number: $Revision: 1.9 $ Date Last Revised: $Date: 1995/08/02 23:40:30 $ Description of Problem ---------------------- The subtype checking described in LRM 8.5 appears incorrect. First, it does not deal properly with an OUT mode parameter since it implies the subtype check for such a parameter takes place prior to the execution of the subprogram. Second, for an INOUT or OUT mode parameter, it does not cover the check when the subprogram completes that the value of the parameter lies within the subtype of the actual. Proposed Resolution ------------------- For scalar procedure parameters we assume that prior to the execution of the subprogram subtype checks are performed for IN and INOUT mode parameters and that after the execution of the subprogram subtype checks are performed for INOUT and OUT mode parameters (as in Ada). VASG-ISAC Analysis & Rationale ------------------------------ TBD VASG-ISAC Recommendation for IEEE Std 1076-1987 ----------------------------------------------- TBD VASG-ISAC Recommendation for Future Revisions --------------------------------------------- TBD