Re: comparing two programs?

abykov@pollux.usc.edu (Alexander Bykov)
Wed, 20 Apr 1994 23:27:58 GMT

          From comp.compilers

Related articles
comparing two programs? abykov@pollux.usc.edu (1994-04-18)
Re: comparing two programs? bosullvn@maths.tcd.ie (Bryan O'Sullivan) (1994-04-19)
Re: comparing two programs? jan@neuroinformatik.ruhr-uni-bochum.de (1994-04-20)
Re: comparing two programs? abykov@pollux.usc.edu (1994-04-20)
Re: comparing two programs? khorsell@ee.latrobe.edu.au (1994-04-26)
Re: comparing two programs? masjpb@midge.bath.ac.uk (1994-04-29)
| List of all articles for this month |

Newsgroups: comp.compilers
From: abykov@pollux.usc.edu (Alexander Bykov)
Keywords: theory
Organization: University of Southern California, Los Angeles, CA
References: 94-04-124 94-04-135
Date: Wed, 20 Apr 1994 23:27:58 GMT

>>I need the program that would compare two programs for being identical.
>You don't say what language your programme's written in...there are some


I am sorry, of course, I forgot to mention very important factor: I need
the analyzer for the following: C, C++, LISP. I already found two
programs: one developed at Berkeley (targeted towards C) and the other
developed at Bellcore (called spiff) which is basically an improvement of
diff program. Spiff is better than diff (for my purpose) because it is
targeted specifically to comparing two PROGRAMS and not just any two text
files.


I am now experimenting with a C analyzer from Berkeley. It was written by
a former Berkeley student and there is no documentation on the meaning of
the program output. It generates a number between 0 and 1. But the meaning
of the number was unclear to me: when programs are absolutely different
the number is close to 0.95... if programs are identical (regardless of
comments, spacing, indentation, variable names) the number is 1. So it is
clear that when the number is 1 then two programs are identical. However,
I suspect, that the number will not be 1 most of the time. So, if 0.95 for
two absolutely different programs and 1 for two absolutely identical
programs then what should the number be for just similar programs (copied
but not exactly identical)? When should I become suspicious?


--- Alex Bykov abykov@pollux.usc.edu
--


Post a followup to this message

Return to the comp.compilers page.
Search the comp.compilers archives again.