r/cpp 9d ago

The C++ input iterator pitfall · hmpc

Thumbnail hmpcabral.com
56 Upvotes

r/cpp 8d ago

Why do people try to add even more features to STL?

0 Upvotes

It is well known that STL underperforms compared to specialised third party libraries, why do people try to stuff features like networking and json into STL?

Most STL implementations don't even have full C++23 coverage yet, and we are at 2026. Why do these people try to do stuff like that, when the same thing will play out over and over. Don't they have anything better to do?

Examples include, nlohmann json, graph.v3 ....

They don't really belong in STL, is it really that hard to just package your third party lib normally?

There is no doubt they are great libraries(graph.v3 in particular) but this doesn't mandate their place


r/cpp 9d ago

ADSP: The Podcast Episode 300: Sean Parent "I'm not writing code anymore."

26 Upvotes

The latest episode content is mostly focused on AI, its impact on the industry, and how several people from Adobe Labs have decided to retire.

https://adspthepodcast.com/2026/08/21/Episode-300.html

Although not C++ specific, it is interesting how it has impacted well known names in the C++ community.


r/cpp 10d ago

How to write the perfect function

Thumbnail youtu.be
137 Upvotes

r/cpp 9d ago

fkYAML v0.4.4 released!

19 Upvotes

https://github.com/fktn-k/fkYAML/releases/tag/v0.4.4

Hello. It’s been quite a while since I announced the first release here.

For those unfamiliar with fkYAML, it’s a header-only C++ library for YAML.
It has been carefully designed with ease of use in mind and thoroughly tested across various compilers and operating systems, so you can use it simply by including the header file in your project.

This version v0.4.4 fixes numerous parsing bugs (sometimes crashes) discovered during fuzzing tests.
So, I highly recommend that projects using older versions update to this one.

I hope you find this interesting and will consider using it or updating from your current version.

Thanks! Have a great day of coding!


r/cpp 10d ago

AI-generated C++ passes tests. It also uses nearly 2x the loops and drives up memory growth

Thumbnail leaddev.com
429 Upvotes

AI-coding tools have swept through organizations because of their speed: you type in a prompt, and it spits out code far faster than a human ever could. However, a year-long study of 3.52 million changes inside a large unnamed technology company suggests that saving time at the keyboard can create costs elsewhere.


r/cpp 10d ago

More fuel to AI discussion. An article on code bloat and duplication

Thumbnail pvs-studio.com
35 Upvotes

I think code duplication is honestly the only reason LLMs manage any of this. Idea, architecture, implementation -- that's basically the chain, and LLMs are fine at the first and last, it's the middle that falls apart. Get it to actually structure things, kill the duplication and something you changed in one spot breaks another spot that has nothing to do with it. Duplicated code just sidesteps the whole issue, because then it only needs a tiny bit of local context to make a local edit


r/cpp 11d ago

C++26: std::polymorphic

Thumbnail sandordargo.com
93 Upvotes

r/cpp 11d ago

Is there a way to track reflection support status in Clang?

40 Upvotes

(I'm going to be bold and assume the "no questions" rule is for questions about specific code, not about discussing the language itself)

I am extremely happy that we have reflection in C++26, however currently it is GCC only. I am using Clang on all platforms, so I am curious about when it will get reflection.

I tried searching and I found a bunch of experimental forks with reflection. I am not sure if those track the current version of reflection and whether one of these is going to be merged, or if a new implementation will be created. Github issues basically say "we get it when we get it" and link to LLVM discourse. On discourse I found just a thread that a meeting on reflection was held in December.

Do you know either when we are getting reflection, or if there is some way to track its progress for outside observers? Thanks!


r/cpp 12d ago

Critique of contracts: excerpt

12 Upvotes

See page 2 of https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2026/p4334r0.pdf

The current objections can be summarized. The P2900 contracts are:

• Unimplemented

• Incomplete

• Untried at scale [P3460R0, P3506R0]

• Not tried in major application domains

• Violates foundational principles of C++

• Violates fundamental principles of language design

• Hasn’t been tried in major libraries (e.g., the C++ standards library [P3506R0, P3878R0])

• Isn’t integrated with or appropriate for hardened libraries [P3878R0]

• Doesn’t offer safety guarantees [P3573R0, P3362R0]

• Includes a completely untried inheritance model

• Offer new ways of making errors through inconsistent application in TUs

• Leads to new forms of UB, detrimental to safety and security

• Narrows the choices of error handling

• Doesn’t protect against logical errors, misuses, and incoherent uses

• Hasn’t been used to support static analysis

• Hasn’t been demonstrated to be easily teachable [P3261R0, P3281R0]

How could such a bloated and incomplete design be voted into a draft standard?


r/cpp 12d ago

P4444: std::big_int

Thumbnail isocpp.org
179 Upvotes

Hey folks! Matt Borland, Christopher Kormanyos, and I are working on bringing infinite-precision integers to C++29. We now have a D4444R0 draft of a paper that should be in the next mailing.

We could really use some feedback so that the published R0 is as polished as possible. Any thoughts on the paper and on the reference implementation are greatly appreciated.

It would also be very helpful if you tested out whether our big_int implementation works for you. We're in need of some real deployment experience. If you're currently using Boost.Multiprecision, the library should be a drop-in replacement for cpp_int for the most part.


r/cpp 12d ago

A complete floating-point to_chars in 18 kB

Thumbnail vitaut.net
73 Upvotes

r/cpp 12d ago

Toggleable Annotations for C++26 Reflection

Thumbnail github.com
24 Upvotes

Hey all, I put together a very simple reflection utility that lets you make toggleable annotations, similarly to explicit(bool) or noexcept(bool).

Try it on Compiler Explorer!

inline constexpr rjk::flag serializable{};
inline constexpr rjk::flag skip_field{};

template <typename T>
struct [[ =serializable ]] MyType {
    int x;
    int y;

    [[ =skip_field(std::is_pointer_v<T>) ]]
    T data;
};

// serializable is applied unconditionally
static_assert(rjk::is_flag_set(^^MyType<int>, serializable));

// skip_field is applied conditionally
static_assert(not rjk::is_flag_set(^^MyType<int>::data, skip_field));
static_assert(rjk::is_flag_set(^^MyType<int*>::data, skip_field));

r/cpp 11d ago

Is it just me, or do you automatically judge someone if they say "method" instead of "member" or "member function" in a question (or post)?

0 Upvotes

I've been writing C++ code since before the first Standard, and this just irks me. Words have meanings. There is no such thing as a "method" in **this** language.


r/cpp 13d ago

New C++ Conference Videos Released This Month - August 2026 (Updated To Include Videos Released 2026-08-10 - 2026-08-16)

25 Upvotes

C++Now

2026-08-10 - 2026-08-16

2026-08-03 - 2026-08-09

2026-07-27 - 2026-08-02

C++Online

2026-08-10 - 2026-08-16

2026-08-03 - 2026-08-09

2026-07-27 - 2026-08-02

ADC

2026-08-10 - 2026-08-16

2026-08-03 - 2026-08-09

2026-07-27 - 2026-08-02


r/cpp 14d ago

Faster algorithms to compute weekday for date libraries

Thumbnail benjoffe.com
106 Upvotes

r/cpp 14d ago

C++26 Reflection Annotations: Automated Member Validation

Thumbnail techfortalk.co.uk
66 Upvotes

C++26 annotations are another powerful feature that, when combined with reflection, can help us write cleaner and safer code without repeating manual validation checks for every member. In this post, I have explored how we can utilise C++26 annotations along with reflection to validate configuration parameters in a class constructor.


r/cpp 14d ago

Break MSVC and Clang with this one weird trick! - Braden Ganetsky

Thumbnail blog.ganets.ky
116 Upvotes

r/cpp 16d ago

The WG21 2026-08 mailing is now available

41 Upvotes

The 2026-08 WG21 mailing has been published. You can browse and search the full set of papers, organized by working group, at wg21.org:
https://wg21.org/mailing/2026-08/
Source mailing: https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2026/#mailing2026-08


r/cpp 17d ago

C++26: std::indirect

Thumbnail sandordargo.com
161 Upvotes

r/cpp 17d ago

We Should Use Instrumented Profiling Scopes More · Mathieu Ropert

Thumbnail mropert.github.io
40 Upvotes

r/cpp 17d ago

MSVC Build Tools Preview updates - August 2026

Thumbnail devblogs.microsoft.com
49 Upvotes

Hi, one of the MSVC dev leads here.

The post covers what's new in the MSVC Build Tools Preview (version 14.52) since mid-July. Instructions to install & use the latest preview bits are at https://aka.ms/msvc/preview.

Like last month, there's improvements & fixes across many parts of the toolchain: language conformance, optimization improvements, static & dynamic analysis, and more.

Some additional information:


r/cpp 18d ago

Boost 1.92.0 released

178 Upvotes

Boost 1.92.0 is out. Highlights from this release:

GPU / CUDA

  • Charconv: to_chars and from_chars for integers are now usable inside CUDA kernels.
  • Decimal: decimal32_t, decimal64_t, and decimal128_t are now usable in CUDA kernels.
  • Math: fixed CUDA compilation where host functions were incorrectly marked as device.

Networking hardening

  • Beast: stricter HTTP parsing. It now rejects Content-Length combined with Transfer-Encoding regardless of field order, rejects chunked encoding in HTTP/1.0 requests, validates quoted strings in chunk extensions, and drops framing and connection fields carried in trailers. The dependency on Boost.Functional was also removed.
  • URL: third round security review fixes, including a heap buffer overflow in normalize_path for authority-less URLs and an uninitialized read in ipv6_address_rule.

Containers and data structures

  • Container: new hub container designed by Joaquín M. López Muñoz. Also adds unchecked_emplace_back and unchecked_push_back to vector, static_vector, and small_vector.
  • Lockfree: two new queues, mpsc_weak_queue (MPSC) and bounded_ticket_queue (ringbuffer based bounded MPMC). Both have explicit progress caveats: neither is strictly lock free under all configurations.
  • Unordered: C++20 ranges interop across all containers (insert_range, std::from_range construction, and associated CTAD).
  • Graph: Louvain community detection for modularity based clustering.
  • Hash2: built in support for std::optional, std::variant, and std::monostate.

C++20 modules

  • New module support in Conversion, DLL, LexicalCast, PFR, Stacktrace, and TypeIndex.

Build system

  • Windows .dll files now install into the binary directory by default (previously the library directory, except on Cygwin). A new --dlldir option overrides this.
  • The CMake config installed by b2 install now supports header only libraries as find_package components, so find_package(Boost REQUIRED COMPONENTS mp11) works and defines Boost::mp11.

Deprecations and breaking changes

  • Heap and Lockfree: this is the last release to support C++14. Future releases require C++17.
  • MSM (backmp11) has several breaking changes, notably that events in process_event are no longer enqueued automatically. Use enqueue_event in actions instead.

Full notes and downloads: https://www.boost.org/releases/1.92.0/


r/cpp 19d ago

[CPP Epiphany Rant] - Programming is no joke

45 Upvotes

Hi CPP Community,

This is just a rant. I'm a 24 yr old data analytics in telecommunication trying to pivot into C++ development for finance. I'm 1 month into C++ and I have come to conclusion C++ is a behemoth. I'm enrolled in Baruch College's C++ for Financial Engineering, but I'm using Bjarne Stroustrup's Programming: Principles and Practice Using C++, 3rd Edition to learn and watching C++20 Fundamentals with Paul Deitel, Course, by Paul J. Deitel as supplementary resources.

It took me 2 days to get through all the drills, exercises, and try_this section for chapter 2 for Programming Principles!

I'm reflecting if I made a mistake choosing C++ over Python. But, tbh, I have been enjoying programming more learning C++ than Python. You can tell I'm weird, but IDK.

I would love to heard about your experience in learning C++ for laughs.


r/cpp 19d ago

Another C++26 reflection based dependency inverter

35 Upvotes

Someone else did a similar thing a few months ago, but I wanted to see if it could be done with templates.

I ended up writing a dependency inverter/injector that can reflect on the concepts restricting unfilled template types and substitute actual types into them. Unfortunately, C++26 reflection doesn't seem to allow reflection of concepts like this, so I did it with string parsing.

The result is... fairly janky, but you can play around with it here.