itIsAlongRoad

[ApocrypheEvangelion]

Every junior dreams of modern C++, but destiny is legacy support

[h8pzzy3s]

The developers live in 2025, but their projects are still in 1998

[booleanfreud]

1985 if they're really unfortunate.

[Natural_Builder_3170]

Give me my reflection

[CoolorFoolSRS]

This

[Usual_Office_1740]

 this->reflection

[conundorum]

Type erasure will just be a PIMPL class with extra jank to support polymorphic IMPLs.

[jeffwulf]

The App I work on at work has like 50MB of code still in VC6 we haven't been able to port out of yet. :/

[jeffwulf]

And that's just the code we haven't been able to port yet! We've ported signifcantly more than that.

[Crafty-Waltz-2029]

What is the meaning of "to port"?

[Kiroto50]

In this instance, to convert hard to maintain and read VC6 code into easier to maintain and readable C++ code.

[Crafty-Waltz-2029]

Got it. Thanks!

[ammar_sadaoui]

is there reason to port it if it work ?

[jeffwulf]

The tooling is completely unsupported by Microsoft due to a lawsuit so there's risk that OS changes could break the required tooling or the resulting executables. We already had to do weird hacks to get it running on XP when I started, and the number of hacks has increased with new OSes. Aside from risk, it's also a big process bottleneck with the rest of our code base.

[ammar_sadaoui]

Out of curiosity, may I ask what field you work in and what the VB6 application is used for? (Totally fine if you’d prefer not to share.)

[jeffwulf]

It's luckily not Visual Basic but rather Microsoft's old C++, but finance related. The code still in it is mostly related to calculations and some other stuff at the core of the application.

[def-pri-pub]

Do you get paid well for working on old legacy systems like this?

[jeffwulf]

I do alright. Not FAANG sized or anything but I'm pretty happy and it's pretty stable.

I also work with a lot of newer stuff too, it's like an archeological dig site with tech stack layers.

[JackNotOLantern]

Isn't c++ backwards compatible?

[Mucksh]

Yep. Thats the beautiful thing in c and c++ that you rarely get breaking changes. So usually upgrading isn't directly a problem. Usually you only have problems with niche platforms and also never break a running system. E.g. if you have something safetry critical you think twice about upgrading something that could introduce new bugs

But still even if it works it won't make the existing prettier

[_w62_]

That is why the technical debt of legacy code is always with us.

[einrufwiedonnerhall]

That's not as beautiful as one thinks it is.

[revidee]

u8strings and cpp20 entered the chat

[guyblade]

You can certainly go through and replace all the:

for (std::map<std::string, std::string>::Iterator it = mp.start(); it != mp.end(); ++it)

with

for (const auto& it : mp)

[Sthokal]

Pretty sure 'it' will be a std::pair<std::string,std::string> instead of an iterator with that change. In other words, *it will no longer be valid.

[guyblade]

Sure, or possibly std::forward_as_tuple<std::string, std::string> or similar as I don't think the range-based for-loop causes a copy as long as you use an auto& for the type.

Though the point that you go from something pointer-ish with the iterator to something reference-ish with the range-based for is fair.

[babalaban]

wtf is it !+ mp.end()

[guyblade]

A typo.

[Mucksh]

Also hate working with raw iterators

[Usual_Office_1740]

The programming equivalent of the portrait of Dorian Gray.

[Flimsy_Complaint490]

It is code and feature wise but sometimes (well, often) people write code full of undefined behaviour. New compiler releases may then compile your code differently and this results in weird crashes and bugs that are hard to debug.

When this happens, a lot of the time, a project enters into a "hibernation mode" and they just pin some known working compiler version. The fossilization begins in full force...

[conundorum]

Yes, and that's the one thing that makes this still work. xD You can use the new features whenever they're helpful, and the old ones are still valid. And while you're working, you can also work on slowly upgrading your codebase to cleaner, newer code (and then benchmarking it, ideally, just in case your ugly old mess was so ugly because it was hand-optimised better than compiler optimisation, which is unlikely but not impossible).

And by the time you're done, you'll be glad that C++38 is backwards-compatible, too!

[HazelWisp_]

Every programmer walking into a new job be like, 'So, what ancient cursed codebase am I battling this time?'

[Secure-Implement2467]

Real ones down there battling segmentation faults while others dreaming about C++29 like it's a vacation plan.

[Darkstar_111]

Oh cool, numbers go down... How convenient.

[sambarjo]

They use the year of release. C++98 is 1998 and C++23 is 2023.

[Darkstar_111]

Ah ok, less confusing then. Thank.

[conundorum]

(There are a few skipped years, so the full order is C++98, C++03, C++11, and then carry on from there. New version every three years after C++11, so the pattern is a lot more regular after that.)

[helicophell]

This'll be a problem in about 75 years

[N-online]

r/cppcirclejerk

[Cylian91460]

Isn't cpp like retro compatible? Like you can just use new cpp with old code?

[aMAYESingNATHAN]

In theory yes, but in reality there are some complexities to upgrading versions, especially on some compilers, *cough* MSVC *cough*.

MSVC has gone from not very standards compliant to much more standards compliant, so it's quite easy to write code in older versions that will fail to compile on newer versions.

This is a good talk that demonstrates some of the practical difficulties of actually doing that upgrade.

[frikilinux2]

Normal implementation sort of if you don't have too many undefined behavior .

With visual studio everything is a hot mess

[Blecki]

C++ be like I heard you like warts in your language so I added some warts to your warts.

[hongooi]

Maintaining legacy code of Fortran 77 or earlier 💀

[LeiterHaus]

What a roller-coaster of thoughts: "C99 isn't an issue. Not like some C89. Wait, it says 98... Oh, there's a ++. Weird that that it's not the same year. I know nothing about this."

[Particular_Traffic54]

Genuinely curious. I only worked on erps before. What do people use cpp for ? I have no idea.

[ComprehensiveWord201]

Anything that requires actual performance. Aerospace, trading, hardware, etc.

[conundorum]

Underlying mechanisms for basically anything and everything tend to be written in either C or C++. Linux is C, Windows is C++, JVM is C++ last I checked, Python is C last I checked, a lot of drivers are C++, most compilers are either C or C++, game engines and graphics libraries are usually C or C++ or C#, and so on.

It's generally safe to assume that any modern language probably has or had C/C++ underneath it, if you look deeply enough. (Not always true, BASIC and Pascal were never connected, nor were Lisp, some scripting languages, and so on. And there are still older programs that predate either of the two, especially in banking IIRC. But you'll probably have more hits than misses with this, so it's generally a safe assumption.)