Using Redundancies to Find Errors

gsbarnes writes "Two Stanford researchers (Dawson Engler and Yichen Xie) have written a paper (pdf) showing that seemingly harmless redundant code is frequently a sign of not so harmless errors. Examples of redundant code: assigning a variable to itself, or dead code (code that is never reached). Some of their examples are obvious errors, some of them subtle. All are taken from a version of the Linux kernel (presumably they have already reported the bugs they found). Two interesting lessons: Apparently harmless mistakes often indicate serious troubles, so run lint and pay attention to its output. Also, in addition to its obvious practical uses, Linux provides a huge open codebase useful for researchers investigating questions about software engineering."

Comments

Is this not Obvious

[goombah99]

so run lint and pay attention to its output.

pardon me, but DUH???

I Hope They Didn't Get Paid

[the_mad_poster]

I seriously hope no one paid them for this.

Are they telling me that if I write useless code intentionally I'm increasing my chance of errors as I increase my code?

Or, maybe they're saying that if I write useless code by mistake, I'm being careless which invites more errors?

Brilliant insight... I wish I had thought of all that before I turned my clear, concise 10 line application into a mangled mess of 100000 lines (hey look... I just rewrote the Windoze kernel!)

talk about redundant

[Cheeze]

the article is in a pdf. now that redundancy.

are they just too lazy to "export to html" and put it up as a webpage?

and no, i don't want to load the adobe viewer. 30 megs of ram for a viewer program? there's probably 80% redundant code loaded into memory in that program alone