-------------BEGINNING OF IR---------------- VHDL Issue Number: 2061 Language_Version VHDL-2002 Classification Language Definition Problem Summary Default actions on severity flags is different between simulators Relevant_LRM_Sections Related_Issues Key_Words_and_Phrases Authors_Name Jim Lewis Authors_Phone_Number 503-590-4787 Authors_Fax_Number Authors_Email_Address jim@synthworks.com Authors_Affiliation Authors_Address1 Authors_Address2 Authors_Address3 Current Status: VASG-Approved Superseded By: ------------------------ Date Submitted: 10 February 2005 Date Analyzed: 18 February 2005 Author of Analysis: Chuck Swart Revision Number: 4 Date Last Revised: 15 November 2005 Description of Problem ---------------------- Both users and standards groups (those developing packages) are hampered by the fact different simulators do different things with severity error. It appears that some simulators stop on severity error and some do not. In the package numeric_std there are some things that are currently severity warning that should have been severity error. There is resistance to changing them to severity error because this would make the package execute differently under some simulators. This is a problem. As engineers, we need one definition of what these flags do by default. Proposed Resolution ------------------- By default, all simulators shall print messages of severity error but not stop. By default all simulators shall stop on severity failure. VASG-ISAC Analysis & Rationale ------------------------------ Different default behaviors between simulators have created problems with package design. The ISAC suggests that the LRM recommend that the default action for simulators is to continue execution for severity messages error and below. VASG-ISAC Recommendation for IEEE Std 1076-2002 ----------------------------------------------- No change. VASG-ISAC Recommendation for Future Revisions --------------------------------------------- Clause 0.2 Structure and terminology of this standard add: The word should is used to indicate a recommendation. Clause 8.2 Assertion statement After the paragraph starting "The error message consists of at least..." Add a paragraph: An implementation should continue execution of a model after occurrence of an assertion violation in which the severity level is NOTE, WARNING or ERROR. Add the note: NOTE: An implementation may choose whether or not to continue execution of a model after occurrence of assertion violations with various severity levels. It may also give tool users ability to control simulator actions for assertions of various severity levels via mechanisms not specified by this document. Similarly, Clause 8.3 Report statement After the paragraph starting "The report message consists of at least..." Add a paragraph: An implementation should continue execution of a model after executing a report statement in which the severity level is NOTE, WARNING or ERROR. Add the note: NOTE: An implementation may choose whether or not to continue execution of a model after occurrence of report statements with various severity levels. It may also give tool users ability to control simulator actions for report statements of various severity levels via mechanisms not specified by this document. -------------END OF IR----------------