From: Krishna Garlapati (firstname.lastname@example.org)
Date: Tue May 20 2003 - 10:00:02 PDT
The following reply was made to PR enhancement/350; it has been noted by GNATS.
From: Krishna Garlapati <email@example.com>
Subject: Re: enhancement/350: Proposal to deprecate configs in Verilog source
Date: Tue, 20 May 2003 09:58:22 -0700
This is a very neat idea. Seperating link info from source code
makes most practical sense.
>Verilog-2001 allows configs to appear in either Verilog
>source files, or the library map file. I am proposing
>that they not be allowed in Verilog source files, only
>in the library map file.
>The main reason for proposing this is that configs use
>a lot of reserved keywords that can create backward
>compatibility problems for existing designs. A test on
>a large set of real customer designs indicated that 15%
>of them would not compile with these keywords reserved.
>And before anyone suggests context-sensitive keywords
>(blech!), the main offender was the keyword "config",
>which marks the start of the context and therefore
>can't be context-sensitive.
>The idea of having configs in the source code presumably
>came from VHDL. Most experienced Verilog people I have
>consulted agree that Verilog source files should only
>contain real Verilog source, and that configs should be
>put in a side file. The existing standard already allows
>for them to be put into the library map file, which fits
>that description nicely.
>Nor is putting configs in the Verilog source file the
>most beneficial use model. If you want to change what are
>effectively "link" options, you don't want to have to
>change and recompile the source code each time. My
>inquiries indicate that VHDL users most often supply
>configs in separate files, usually generated by tools
>and at most tweaked by hand. So this seems to be the
>most natural way of using them anyway.
>If we do deprecate this, it would be best to do it
>soon and publicize it before it comes into wide use.
- Krishna Garlapati, Synplicity Inc. (408)215-6152
This archive was generated by hypermail 2.1.4
: Tue May 20 2003 - 10:00:50 PDT
sponsored by Boyd Technology, Inc.