Re: Please, no knee-jerk "no goto ever" reactions

Posted Dec 30, 2014 3:00 UTC (Tue) by flussence (guest, #85566)
In reply to: Re: Please, no knee-jerk "no goto ever" reactions by ldo
Parent article: The "too small to fail" memory-allocation rule

Your code already uses gotos - albeit each one rendered with an indented, gaudy costume of do-break-while-0 euphemism.

But the compiler can see your royal highness is stark naked. And so can we.

Re: Please, no knee-jerk "no goto ever" reactions

Posted Dec 30, 2014 9:47 UTC (Tue) by anselm (subscriber, #2796) [Link] (1 responses)

GOTO used to be a real problem when it was all that people had for control flow (think 1960s-era FORTRAN).

Right now with the proper discipline I don't have a huge problem with “goto” in C. As far as I'm concerned it is way less of a problem for program structure than the style that ldo is advocating. ldo's style also seems to presuppose that “cleanup” consists exclusively of undoing earlier things in reverse order; in general one might have to do things in an error branch that one might not have to do during normal flow, and sorting these cases out just serves to make the code even more convoluted on top of all the extraneous “do { … } while (0)” and “if (…) break” constructs.

I teach programming as my day job (some of the time, anyway), and I can guarantee that anybody who came to me with code like ldo's would get a very stern talking-to.

Re: in general one might have to do things in an error branch that one might not have to do during normal flow

Posted Dec 30, 2014 20:53 UTC (Tue) by ldo (guest, #40946) [Link]

I believe this is another instance of the “cleanup” versus “rollback” argument made elsewhere. See my comments about idempotency of deallocation routines and NULLing subsumed pointers.