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C Questions and Answers

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Re: C Questions and Answers

#41

Post by sjolsen »

belovedeagle wrote: post #11

> (especially C programmers) Author needs to stop his anti-intellectual everyone-is-as-ignorant-as-me bullshit. I see that a lot re programming to justify a lot of silly positions. If you only know Javascript, that's great, I rather like having shiny things in my browser (I like it too much, even). That doesn't mean that C programming is obsolete; some of us know C. For example, I got #5 and #9 wrong, and the rest I…

I don't believe the author is claiming that C is obsolete; nor do I believe he is claiming that no one knows C.

What I do think he's implying, if not outright claiming, is that there are many people who grossly overestimate their knowledge of the language. That doesn't mean there aren't a lot of very talented and knowledgeable C programmers— but there are a lot of people out there who think they're hot shit because they've done all the exercises in K&R, but who have no real familiarity with the formal semantics of standard C.

Re: C Questions and Answers

#42

Post by fizixer »

obstinate wrote: post #27
fizixer wrote: post #5

He's discussing subtle points of the C language and yet there is no mention of which compiler he's using, whether the results might be different for different compilers, hardware platforms, and how they correlate with multiple C standards (C89, C99, C11/C1X, etc). He succeeded in convincing me that he does not know C!

Since he's talking about undefined behavior in a lot of the cases, the answer to all your questions is, "Yes." That's pretty obvious, so maybe he thought it went without saying.

Not sure which of my questions you're referring to.

As I replied to others, saying "bar() is invoked" is not only not obvious, it's incorrect. bar() may or may not be invoked.

Re: C Questions and Answers

#43

Post by cbsmith »

ChuckMcM wrote: post #30

I think this was silly, the author clearly does know C but they are complaining about optimizing compilers which do things "behind your back" and are becoming an increasing nuisance. It's sort of a passive aggressive "I think this should be an error but it isn't an error because twisted logic that the compiler uses with respect to undefined operation." That people can teach themselves what to expect the compiler to d…

> they are complaining about optimizing compilers which do things "behind your back" and are becoming an increasing nuisance.

Actually no. I think there was maybe one case where you could argue it was the optimizer that is producing different results than you'd expect for unoptimized output, but in most cases you have a problem that exists because of poor assumptions on the part of programmers/error prone language definitions.

Re: C Questions and Answers

#44

Post by cbsmith »

ternaryoperator wrote: post #14

This reminds of me of the Quiz books that were popular years ago. They'd show some code that inadvertently tripped some obscure corner of the language. Rarely did the quizzes provide great insight. Rather, they confirmed the benefits of keeping your code idiomatic.

Sadly, much of this code is idiomatic.

Re: C Questions and Answers

#45

Post by sjolsen »

ChuckMcM wrote: post #30

I think this was silly, the author clearly does know C but they are complaining about optimizing compilers which do things "behind your back" and are becoming an increasing nuisance. It's sort of a passive aggressive "I think this should be an error but it isn't an error because twisted logic that the compiler uses with respect to undefined operation." That people can teach themselves what to expect the compiler to d…

>I think this was silly, the author clearly does know C but they are complaining about optimizing compilers which do things "behind your back" and are becoming an increasing nuisance

I think the compiler behaviour is meant to be illustrative of the main point, not the main point itself, which I think is simply that the actual C language is more complicated than people appreciate. Most of the examples have nothing to do with optimization whatsoever; they're purely focused on correctness.

Re: C Questions and Answers

#48

Post by cbsmith »

_RPM wrote: post #2

This reminds me of tests I took in earlier CS classes. Knowing those things are utterly useless in practice.

A lot of these are cases where I've seen actual bugs. Popular ones are >= 0 checks, dumb assumptions about overflows and null derefs, and the always popular "use an int when it should be size_t".

Re: C Questions and Answers

#49

Post by cbsmith »

anon4 wrote: post #38
bgvopg wrote: post #15

Earlier quoted context omitted.

Some would twitch at this: for(i = length - 1; i but it is completely valid.

just fucking use for(i = 0; i I've been much happier since I started writing all loops as incrementing loops.

    for (i = 0; i
It's not about the incrementing vs. decrementing so much as the equality bounded loop on a value that could be a min/max value. Gets you every time.

Re: C Questions and Answers

#50

Post by oneeyedpigeon »

belovedeagle wrote: post #11

> (especially C programmers) Author needs to stop his anti-intellectual everyone-is-as-ignorant-as-me bullshit. I see that a lot re programming to justify a lot of silly positions. If you only know Javascript, that's great, I rather like having shiny things in my browser (I like it too much, even). That doesn't mean that C programming is obsolete; some of us know C. For example, I got #5 and #9 wrong, and the rest I…

I think the opinions "c is too complicated and buggy and, therefore, obsolete" and "javascript is a 'shiny' language for amateurs" are just as narrow-minded as each other.
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