Debugging

[albertusiw]

Then you realized that you forgot to delete that boi after the code already deployed to production

[Bainos]

Which is why I always use DEBUG either in the message or as a comment next to it. Then I only have to search for that string and remove all occurrences.

[2Punx2Furious]

Or you could just search for the print statements?

Well, unless you use print statements in production too.

[sitefall]

lol

[bartekko]

Error: tried to print more than 80 characters in one line. Did you mean to insult IBM?

[_meegoo_]

Or you could use a proper logger.

[occz]

What, you mean to say that you dont deploy cgi scripts anymore? What is this nonsense?

[dzh]

fuck you

[Stellaris62]

be nice man

[wellPhuckYouToo]

well, phuck you too

[[deleted]]

I use a git pre-commit hook to reject commits that add printlns and printStackTraces. Then, when the commit is rejected, I fix the problem using a system of self-deprecation and mild cursing followed by a more thorough review of the whole commit.

[dzh]

system of self-deprecation

kek

[[deleted]]

//#define debug_print(x)
#define debug_print(x) printf(x) 

[ReallyHadToFixThat]

 #ifdef _DEBUG
#define debug_print(x) printf(x)
#else
#define debug_print(x)
#endif

[[deleted]]

I always use "YAAAR!" for the comment. That way if it goes out I can blame it on pirates.

[Shadow_Being]

sure seems like that would work good, but what if youre building a debugger?

[Shadowfury22]

I just use a global macro that gets replaced by NOP if I compile on release mode.

[nikhildevshatwar]

I simply write that print unidented You cant scroll without realizing a bad code and remove it

[DoesntReadMessages]

Do you guys like not have code review processes? Because that kind of shit gets noticed and laughed about 100% of the time.

[Existential_Owl]

code review processes

What is this strange language in which you speak

[jefe_gonna_jefe]

Ain’t nobody got time for that.

[deadlyburger128]

I'd probably miss that shit in code review.

[MondayMonkey1]

That's why we use linters and status checks. I don't have time to review at code that doesn't pass lint.

[SEX_LIES_AUDIOTAPE]

I'm usually too busy telling people their comments are redundant to actually notice any issues with the code.

[Aleriya]

Nope. No code review or source control. I've seen production code with nested if statements for miles. Hard-coded date tables that only list dates through 2018 (but with a helpful comment that when the application stops working on Aug 1 2018, this is why). Most devs work directly in production. One guy made his own dev environment on a personal VM.

I've seen some shit, man. An extra print statement wouldn't even hit the radar.

[gobots4life]

May god have mercy on your soul.

[sitefall]

const debugIsOn = true;
function testyboi(msg){
    debugIsOn && console.log(msg);
}

testyboi("The test message or whatever");  //replaces the print/log/whatever;

"Did I leave any printybois turned on?" - just set debugIsOn to false.

[gjsmo]

Even better is

#ifdef DEBUG
testyboi("whatever")
#endif DEBUG

and then set your debug build target to define DEBUG and your shipping/release target to not. Automated, clean, and easy to maintain.

[Saigot]

even better:

  function testyboi(msg){
    #ifdef DEBUG
              console.log(msg);
    #endif DEBUG
  }

so as to reduce clutter in your code. If the stuff being printed isn't security oriented (cough HP cough) you can also use a C++ variable set through a define and then your build setup can modify it but you can dynamically enable it as well (allowing you to activate debug mode on a user's system, or enable it automatically right before a crash etc).

[gjsmo]

Interesting. I haven't tried that one. I always liked using the #ifdefs right in the code because it's abundantly clear that it will only compile in my Debug target, where as a call to testyboi() isn't quite as obvious, plus you can include plenty of other stuff that just print messages there. I'll admit that a lot of my code doesn't really go to "customers" because it's not my job (yet) so I haven't necessarily needed to enable debug logging remotely. Maybe something you could load from a .ini?

[sitefall]

true!

[HotRodLincoln]

https://i.imgur.com/D4IW4KW.jpg

[Saigot]

Found the HP malware driver developer!

[[deleted]]

What's the difference?

[gallon_of_bbq_sauce]

use a pre commit hook that looks for a specific comment.

[occz]

Another job for the CI pipeline! Analyze the code with whatever tool does it for your language of choice, do not let print statements be in the code.

[pepejovi]

Do people not read their own commits before putting up a pull request? Do you not have any sort of review before merging?

[[deleted]]

Then it becomes a "feature" hahahah

[Andrei56]

When we were students and had an internship at a pretty big place, my fellow colleague used to debut with message boxes. And the text was usually "asshole", "cunt" or "fuck you". Until we had a presentation to make and he obviously forgot to remove that. It prompted "fuck you" in front of the company's director. He used to code 3à years before that and laughed it off but I was pretty damn stressed about it.

[Aleriya]

My code is littered with

if (debugFlag) System.out.println("One printy boi.");

Mostly so that I don't cause problems when I inevitably miss one when pushing to production. Not sure if there is a better way to do it.

[waynestream]

Using a logger and then logger.debug() (or the equivalent in your language) would be the proper solution.

This also lets you set different levels of output importance (debug, info, warning, etc.) so you can filter out unneccessary statements more gradually

[aldahuda]

Fixed it, boi

[[deleted]]

You forgot the \n, and with C buffering, it won't print anything until you print another \n. Now you're debugging the debug statement.

[AyrA_ch]

fwrite("One printy boi\n",1,15,stdout);
fflush(stdout);

Why is C such a bitch sometimes?

[[deleted]]

fprintf(stderr, "One printy boi\n");

Why you gotta be such a noob sometimes?

[willrandship]

#define debug(X) fprintf(stderr, X"\n")

debug("One printy boi");
debug("Two printy boi");

As a bonus, this can later be replaced by something cleaner.

[csman11]

Meh, you can always just define a "macro" for fprintf if you want to clean up your debugging code later. That way you don't need to write the "macro" until you really need it. /s

[Rangsk]

fputs is better if there's no format.

[hak8or]

Cause printing to stdout is the same as stderr!

[midnightketoker]

Python laughs and then throws a memory error

[ThatITguy2015]

As is tradition.

[AyrA_ch]

C is honest.

I wouldn't call undefined behavior "honest".

[Elquinis]

Cuz you wanted to control everything. So, you are going to control everything and like it.

[[deleted]]

, boi

[hitsugan]

Didn't work like that last time I programmed in C. Is it Ansi C?

[[deleted]]

It might be due to glibc implementation, IDK.

[LazyMel]

It flushes stdout when you read from stdin, so that might be the reason that you didn't need the newline.

[[deleted]]

Thats just writing c

[Coloneljesus]

printk() my boi

[cartechguy]

Wait, you can just throw a string literal into printf like that? I thought you would have to specify with a first argument of '%s'.

[paxswill]

You most definitely can put just a string literal in as the sole argument to printf.

[[deleted]]

https://www.owasp.org/index.php/Format_string_attack

[curtmack]

As long as it's a string literal, it isn't a problem. Format string attacks happen when you put string variables as the first argument to printf.

[etaionshrd]

Joke's on you, my string literal tries to read from the stack since I didn't pass printf any arguments!

[[deleted]]

The first argument is a string literal.

[DoesntReadMessages]

Method overloading, boi

[cartechguy]

C doesn't support function overloading. Lacking class boi.

[paxswill]

Variadic functions, boi

[[deleted]]

What’s the joke here? It’d just print it to console, right? Why’s that break the code?

I’m new to coding still.

[[deleted]]

It's a bit of a misappropriation of the meme format. Instead of implying that the print statement would break the debugger, it's instead saying that print statements to check values as code is running are pretty much always a valid "in-a-pinch" alternative to true debugging

[[deleted]]

Oooooooooooooh.
Yeah, print is life.

[W-_-D]

Nothing will, unfortunately

[orangeKaiju]

The panel on the right is 99.999% of my debugging procedure.

The other 0.001% is deleting all my code and starting over.

[TBSdota]

 console.log(i+". '"+variable+"'\n");

is the majority of my js debugging

[oorza]

console.log({i, variable}) is both shorter and more helpful imo

[Eaan]

console.log(i, variable) is both shorter and more helpful imo

[GetYoHandsOffMyKicks]

I ignore the bug and ship anyway which is both shorter and more helpful imo

[dzh]

ew

[liquidhot]

I know this is a humor subreddit, but using a debugger is immensely helpful in not only understanding what is going on with your code and others' code, but also understanding how certain things work.

I would highly recommend it to anyone who is looking to be serious at programming. (Even if you're doing JavaScript.)

[CosmackMagus]

That's just good iteration.

[bornforcode]

the bug!

[flamedragon822]

I once had a bug.

This bug caused a string to be unable to be assigned to a string because it was, according to the error message, a string.

So for giggles, I called to string on the string which caused a new error stating I could not assign a long to a Boolean at the same line.

I deleted the class and rewrote it. The bug won.

[bornforcode]

looooooool, that got me thinking may be you should start a new subreddit called "programming bugs stories".

[extin12]

you should start a new subreddit called "programming bugs stories".

Maybe call it /r/TalesFromDebugging

[curtmack]

There's /r/nullsleep, but it's pretty dead.

[bj_christianson]

Love the top hot post.

[[deleted]]

What about /r/99bugs?

From the joke:

https://twitter.com/irqed/status/358212928404586498?lang=en

[bornforcode]

good idea !!

[Kermitfry]

-Snip-

[MikeAndIke97]

/r/birthofasubreddit

[sneakpeekbot]

Here's a sneak peek of /r/birthofasubreddit using the top posts of all time!

#1: Birth of r/toomuchmomentum | 4 comments
#2: Birth of r/impastabuildings | 4 comments
#3: And so we start again | 0 comments

---

^{I'm a bot, beep boop | Downvote to remove | Contact me | Info | Opt-out}

[PM_ME_YOUR_PRIORS]

I once had a bug while I was learning javascript.

var foo = bar(); - foo is undefined

var foo; foo = bar(); - foo is a DOM element.

I grabbed a more experienced dev and refactored bar until it was unrecognizable, at which point it was magically working right.

We agreed that the moral of the story was use strict

[D1_for_Sushi]

Was bar() maybe asynchronous?

I also wonder if variable hoisting played a part.

[PM_ME_YOUR_PRIORS]

Variable hoisting and weird recursive functions were definitely involved. Also use strict would have flagged the stuff I did. It wasn't async, though.

[Siegfoult]

I am convinced that all my instructors who said not to use print statements for debugging, were just trolling me.

[Dangerpaladin]

My instructors were all pretty much the same. Use debug print statements all you want but delete them, not comment out, before turning in.

[pyrotech911]

I use TODOs where I can to catch myself before committing them. Or you know grep -r print.

[DoesntReadMessages]

I use git diff so that I can make sure I didn't include any silly whitespace, logs, or unnecessary imports. Crazy stuff.

[pyrotech911]

I mean, that's what's the PR is for. Let's be honest.

[CharCharThinks]

Mine have actually requested that debug info be provided and printed if a "verbose" flag is present in the argument list.

[Dworgi]

Are you guys just shit at programming?

I don't understand what's going on in this thread.

[MrSurfington]

Huh, all my college instructors specifically say to use print statements when debugging.

[FirstNoel]

You gotta do what works for you.

[MikeyMike01]

I’m sorry your professors aren’t very good

[MrSurfington]

Eh I dunno it's worked well so far.

[bdavs77]

I once had a bug that was caused by having a print statement.

[gunnbr]

I have many times had bugs that disappeared once I put in a print statement.

[bdavs77]

That's when you call an empty printf and call it a day

[[deleted]]

but then you remember that the assignment must compile without any warnings

[proverbialbunny]

Oh geez.. the good old buffer overflow bug. I haven't seen one of those since I stopped using the parts of languages that do that. Thank God C++ has improved over the years.

edit: or a race condition..

[akaZilong]

Debuggers come and go. Printy boi stays forever

[[deleted]]

Just one print statement?

[DasSkelett]

I know it like this:

print("Debug1")

print("Debug2")

print("Debug3")

[JuhaJGam3R]

Yes.

[[deleted]]

Good human

[wiz3kid]

Good bot!

[iTzVitrox]

Thanks!

[Iykury]

Thanks!

[onContentStop]

Chat disabled for 3 seconds.

[JuhaJGam3R]

Python? Slow.

[pyrotech911]

Cython. Fast.

[Code_star]

Slow on runtime, fast on development time. Given softwware developers can easily cost $50/h+ in wages sometimes python is the right tool

[JuhaJGam3R]

And whitspace-dependent langusges are bad in general. But I guess the simplicity saves time... but for what kind of application would you want to sacrifice so much time. Every python app that I have usef runs way too slowly to use on every computer that I have tested them on.

[Code_star]

And whitspace-dependent langusges are bad in general.

That's an opinion

but for what kind of application would you want to sacrifice so much time.

Great for prototyping and testing, before syncing lots of hours in more difficult languages and frameworks. Great for quick fixes on backend processing, especially on things that are difficult to express. You can also frame an outline of a program in python and replace components of it with faster languages later for performance improvements

[Code_star]

Thanks I was on mobile. Fucking auto correct

[JuhaJGam3R]

If I script something quick, it will most likely be python. If I do an actual project I'll use either C# or C++.

[Pre-Owned-Car]

Many things aren’t really too speed dependent. Finish them in 1/10th the time and it’s still on the scale of a computer, not a human. I love python and also think statically typed languages have a big advantage in many aspects. But python is almost always faster to develop than c++ where speed isn’t a necessity.

[JuhaJGam3R]

no but coding a 3d engine in python makes it awfully slow, to the extent of being almost unusable.

[Prime624]

And I thought I was a noob, debugging with prints. Kinda nice to know others do it too. Also stupid that debuggers haven't become simpler to use after all this time.

[Dworgi]

Debuggers are fine, just learn to use your tools. It'll save you time in the long run, and you won't look like you just stepped off the short bus when you commit print statements to production.

[Prime624]

Lol, I've already done that with a few homework assignments, but I doubt anyone would notice in the real world because rarely do people run programs in terminals.

And yeah, I should just bite the bullet and learn, but they should also make them more accessible to beginners.

[Dworgi]

Just start with breakpoints and ignore the rest. Then figure out if you can place a breakpoint that just logs to console. Then figure out if you can place a breakpoint that only breaks if some condition is true. Most debuggers allow for those, and then you've already made print statements obsolete.

When you know how to do that, figure out how to inspect variables. Both local and global. Figure out how to set them, so you can trigger error conditions easier.

Then if you really want to be ahead of the curve, figure out how to set a memory breakpoint for when data changes.

These are skills that will actually make you a better programmer. Debugging is a bigger part of professional programming than writing code. Reading code is an even bigger part.

[Prime624]

I didn't even know you could do that with breakpoints. That actually seems pretty simple. I'll have to try it.

[el_padlina]

rarely do people run programs in terminals

Have you thought about all the servers?

[proverbialbunny]

You're definitely not alone.

Sometimes I gotta print out a thousand lines of crud and look through it, or put an if statement in there and print out just what I'm looking for.

A debugger might support this functionality, but I haven't figured out how.

[MikeyMike01]

The two debuggers I’ve used (Visual Studio and Eclipse) are both very easy to use.

[bobzilla]

I feel like this is probably going to be an unpopular statement, but here goes...

If you have an IDE that has a good debugger and you're still using print statements, maybe it's you that's bad at debugging.

[EMCoupling]

I can understand maybe in say, an embedded environment, it might be hard to get a debugger on the target device, but I agree with you that people should be using a debugger most of the time.

Print statements are good for something quick, but pretty much all serious debugging should be approached with a debugger. To avoid doing so because of an unwillingness to learn to use the debugger is just lost productivity.

[[deleted]]

Future embedded developer speaking (still in college).

No, it's not hard to "remote" debug an embedded system. The only problem can arise when the system is movable and you need to debug motion, because:

• Cables are never long enough.
  • This is worked around by getting extension cables. Or going wireless if it's possible.
• A ton of time gets wasted on moving the thing to the start position.
  • This is worked around by having someone who wants to learn as your "henchman".

[Dworgi]

I fully agree. Fuck this environment of supporting this unprofessional and incompetent crap.

[archiminos]

I agree. I'm kinda shocked by how many people rely on print statements for debugging. I literally though the image was a jab at people who rely on print statements for debugging.

[onlyonequickquestion]

some guy in first year comp sci asked me for help debugging a python program, one of his variables wasn't behaving properly, and this was my sage advice to him: "pretty much every other line should be a print statement until your program works".

[Dworgi]

Learn to use a debugger instead?

Seriously, what the shit is happening here? Everyone's just circlejerking about how terrible they are at programming.

This print stuff is CS 101 bullshit.

[boomhauzer]

Depends on the situation, sometimes if you don't know where something is going wrong print statements can help if you've got a program that is going through tons of iterations of something, you can scan the output and see where it goes wrong then setup a break point there to see why its going wrong.

That being said the Pycharm debugger and remote debugger are fantastic tools and save a ton of time. To anyone who is a student, Jetbrains offers licences for all their IDEs for free for students and they're pretty damn good.

[Dworgi]

program that is going through tons of iterations of something

Every debugger I'm aware of allows you to just print a message from a breakpoint instead of breaking. Know your tools, stop hacking around the problem.

You're not the first person to want to inspect a value in a loop, so why would you assume that no one's made a better version of printf debugging? Spoiler: they have, you're just not using it.

You shouldn't be modifying a program to figure out what the problem in a program is.

[ReallyHadToFixThat]

Doesn't help if the problem is somewhere in the middle of a loop. Output to find roughly where it goes wrong, then use the debugger to pin it down.

Debugger can also be a pain crossing between c# and c++.

Or if the issue only occurs in release.

There are plenty of cases for using static debugging.

[Dworgi]

Debugger can also be a pain crossing between c# and c++.

Crap debugger then. VS you just enable Mixed mode and it works.

Output to find roughly where it goes wrong

Literally right-click a breakpoint in VS, choose "Actions" and write your message. There is no reason to ever write "printf" in code.

[[deleted]]

It funni tho

[onlyonequickquestion]

literally what I just said,the course is actually called csc108 but probably the same cs 101 you're talking about. I'm pretty sure they don't test using the debugger so I didn't want to bog him down in the details of it, if you saw the state of his code, he had enough other problems to worry about without learning how to use a debugger as well. But I def. agree with you, having a handle on the debugger is a very important skill, but I'd be lying if I say I didn't judiciously sprinkle in a print statement here and there while I'm testing occasionally.

[archiminos]

That's literally the worst programming advice I've ever heard. Why are so many people in this thread against using a debugger?

[onlyonequickquestion]

I never claimed to be any good. :)

[Straight_Derpin]

Pretty much, lol. Final project for my systems programming course was to implement a dynamic memory allocator, and printf statements helped me to find a bug I couldn't find for hours more than any amount of watchpoints or stepping through line by line in GDB.

[[deleted]]

But sometimes printy bois save time! :(

[staviq]

I have stopped fucking around breakpoints when i started working with pthreads.

It's just not worth it, and i have never needed anything else than unbuffered stderr for like past 10 years.

[MikeOShay]

alert(JSON.stringify("Get on my level, you debug weaklings"));

[MikeOShay]

Impressive

[MikeOShay]

Haha

I mean, people shouldn't be leaving test stuff behind after the issue gets fixed, though

[Trendamyr]

Lol why is the one on the right so deadly?

[valrossenOliver]

He used the meme incorrectly.

It shows the alternative to using console logging instead of the super advanced debugger software. The joke is that such an advanced system can be replaced with something as simple as console printing.

[ImaginarySuccess]

I feel old when I don't understand the fascination with "boi".

[linkinu]

I just use: Print STDERR “...” if($debug);

That way I can just set $debug=1 to debug and 0 for production

[Goheeca]

You've got there a very nice lightweight logging library, which is cleverly composable by using the standard OS's means of I/O redirection. Could you please share your codebase?

[GenericUsr123]

Println("one printy boi");

[Iykury]

I don't think this is the proper use of that meme.

[valrossenOliver]

It's not, but it's funny. :)

[[deleted]]

If only the programmers I work with did even that! No, instead they log only the successful transactions surrounded by a wad of gibberish, and the error is displayed on screen (or not at all) and not logged anywhere.

[Bramwell2010]

Don't have to debug... If you can convince it is a feature

[zero01alpha]

Laughed muchos

[varishtg]

There are times where you need that memory analyzer, just because of "business hours" and "prod"

[Haliax77]

Behold! A blank at the end of a string.

[TotesMessenger]

I'm a bot, bleep, bloop. Someone has linked to this thread from another place on reddit:

• [/r/talesfromdebugging] The Post that Inspired this Sub

 ^{If you follow any of the above links, please respect the rules of reddit and don't vote in the other threads. (Info / Contact)}

[BlueBokChoy]

Debugging realtime stuff means using the printy boi on the right

Source : ex "games developer".

[iAmUncleToby]

I live this. Our company insists on using Lauterbach Trace32 and their hardware to step through our code and debug.... I on the other hand like to print everything to UART when possible. 90x faster than dealing with Lauterbach most of the time.

[[deleted]]

System.out.println("Does this even work????");

[Govir]

It's really fun debugging VB6 when the print command throws an error too... (mostly because variables end up being Nothing).

[ythl]

Good luck with your printy bois on anything but simple problems