There are many interesting C++ sites and blogs. There's no need to repeat / copy the contents.

• hacking C++
  • https://hackingcpp.com/
• C++ and other development and devop themes
  • https://www.bogotobogo.com/cplusplus/cpptut.php
• Fluent C++
  • https://www.fluentcpp.com/
• accu.org
  • contents for non-members
• Abseil
  • https://abseil.io/tips/
  • https://abseil.io/blog/
• Bartek (Bartlomiej Filipek)
  • https://www.cppstories.com/p/start-here/
  • https://www.amazon.de/Bartlomiej-Filipek/e/B08FKY9LKP
• Rainer Grimm
  • https://www.grimm-jaud.de/
  • https://www.modernescpp.com/
  • https://www.amazon.de/Rainer-Grimm/e/B006ID8WYY
• Bjarne Stroustrup
  • https://www.stroustrup.com/
  • https://www.amazon.de/Bjarne-Stroustrup/e/B000AQ349S
• Andrei Alexandrescu
  • http://erdani.org/
  • https://www.amazon.de/Andrei-Alexandrescu/e/B001ILKI7K
• Herb Sutter
  • https://herbsutter.com/
  • https://www.amazon.de/Herb-Sutter/e/B001ILHLCK
• Nicolai Josuttis
  • http://www.josuttis.de/
  • https://www.amazon.de/Nicolai-M-Josuttis/e/B001ITYMY2
• Scott Meyers
  • https://www.amazon.de/Scott-Meyers/e/B004BBEYYW/
• John Lakos
  • https://www.youtube.com/results?search_query=John+Lakos+C%2B%2B
  • https://www.amazon.de/John-S-Lakos/e/B00J7WW226
• Jonathan Müller
  • https://www.jonathanmueller.dev/
• Eli Bendersky
  • https://eli.thegreenplace.net/
• Ofek Shilon
  • https://ofekshilon.com/
• Šimon Tóth
  • https://medium.com/@simontoth
  • A Complete Guide to Standard C++ Algorithms
    • https://leanpub.com/cpp-algorithms-guide
    • https://github.com/HappyCerberus/book-cpp-algorithms

• CppCast

• Reference
  • https://en.cppreference.com/w/
• cheatsheet of modern C++ language and library features
  • https://github.com/AnthonyCalandra/modern-cpp-features
• C++ Best Practices
  • https://github.com/cpp-best-practices/cppbestpractices/blob/master/00-Table_of_Contents.md
• C++ Core Guidelines
  • http://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines

• https://github.com/martinmoene/cpp_youtube_channels
• https://hackingcpp.com/cpp/educational_videos.html

• Lists
  • https://en.cppreference.com/w/cpp/links/libs
  • https://project-awesome.org/fffaraz/awesome-cpp
  • https://cpp.libhunt.com/
  • https://github.com/nemequ/single_file_libs
• Boost
  • https://www.boost.org/doc/libs/
• https://abseil.io/
  • https://github.com/abseil/abseil-cpp
• https://github.com/Microsoft/GSL
• https://github.com/facebook/folly
• static / small buffer optimized vectors
  • https://github.com/gharveymn/small_vector
  • https://github.com/gnzlbg/static_vector
  • https://github.com/cristi1990an/Static-Vector
• Enums
  • https://github.com/quicknir/wise_enum
  • https://github.com/aantron/better-enums
• Coroutines to Implement C++ Exceptions
  • https://github.com/eyalz800/zpp_throwing
  • https://docs.google.com/presentation/d/1h1V3z0v9ENwk4BJUMogIttKCgJ9MipmSn49MpKCbi9k/edit#slide=id.p
• Martin Moene
  • https://github.com/gsl-lite/gsl-lite
  • https://github.com/martinmoene/span-lite
  • https://github.com/martinmoene/scope-lite
  • more @ https://github.com/martinmoene
• Scope Exit
  • with LAMBDA and td::unique_ptr
    • https://en.cppreference.com/w/cpp/memory/unique_ptr
    • #include <memory>
    • auto lambda_to_call = [&](void*) { .. };
    • std::unique_ptr<void, decltype(lambda_to_call)> rst((void*)1, lambda_to_call);
  • https://github.com/SergiusTheBest/ScopeExit
  • https://github.com/martinmoene/scope-lite
• (G)UI
  • http://nanapro.org/en-us/
    • https://github.com/cnjinhao/nana
    • http://nanapro.org/en-us/documentation/
    • http://nanapro.org/en-us/blog/
    • http://nanapro.org/en-us/forum/index.php?u=/topic/986/ggbug-when-using-nana-liabry-in-windows-dll/post-2156#post-2156
  • https://github.com/Immediate-Mode-UI/Nuklear
  • https://github.com/rxi/microui
  • https://github.com/andlabs/libui
• (T)UI
  • https://pdcurses.org/
  • https://github.com/mirror/ncurses
  • https://github.com/ldm0/wncurses
  • https://github.com/unicurses/unicurses

• it's really hard to recover from out-of-memory situations
• the program needs the possibility to free (or shrink) some memory resources
• all memory allocations - including utilized libraries - have to be controlled
• that's practically impossible for big applications depending on many external libraries
• Linux and it's OOM-killer need special attention
• related: the requirement for an exception-safe c++ program, so that resources are not leaked
• for most applications, it's not worth that much efforts. thus, let the program terminate or crash (early)!

some Links:

• https://eli.thegreenplace.net/2009/10/30/handling-out-of-memory-conditions-in-c
• https://kristerw.blogspot.com/2015/05/out-of-memory-handling.html
• Linux' OOM-Killer:
  • https://backdrift.org/oom-killer-how-to-create-oom-exclusions-in-linux
  • Dealing with the Linux OOM Killer at the program level
  • How to Adjust Linux Out-Of-Memory Killer Settings ..
  • https://unix.stackexchange.com/questions/432171/completely-disable-oom-killer
  • https://serverfault.com/questions/606185/how-does-vm-overcommit-memory-work
  • https://www.lug-erding.de/blog/2020-05-15-linux-und-overcommit_memory.html

• “Substitution Failure Is Not An Error”
• https://en.cppreference.com/w/cpp/types/enable_if
• https://en.cppreference.com/w/cpp/language/sfinae
• https://eli.thegreenplace.net/2014/sfinae-and-enable_if/
• https://www.fluentcpp.com/2018/05/15/make-sfinae-pretty-1-what-value-sfinae-brings-to-code/
• https://www.fluentcpp.com/2018/05/18/make-sfinae-pretty-2-hidden-beauty-sfinae/

CRTP: injecting/providing methods to a (template) base class through a template class parameter. This might be done to overcome performance penalties of dynamic polymorphism, e.g. to allow inlining.

• https://eli.thegreenplace.net/2011/05/17/the-curiously-recurring-template-pattern-in-c/
• https://eli.thegreenplace.net/2013/12/05/the-cost-of-dynamic-virtual-calls-vs-static-crtp-dispatch-in-c

• https://en.wikipedia.org/wiki/Weak_symbol
• https://ofekshilon.com/2014/02/10/linker-weak-symbols/
• https://stackoverflow.com/questions/13089166/how-to-make-gcc-link-strong-symbol-in-static-library-to-overwrite-weak-symbol

• https://eli.thegreenplace.net/2016/c-raii-without-exceptions/

• 50 terrible coding tips for a C++ developer
  • https://pvs-studio.com/en/blog/posts/cpp/0953/
• The Day The Standard Library Died
  • https://cor3ntin.github.io/posts/abi/

Hyrum's Law:
With a sufficient number of users of an API,
it does not matter what you promise in the contract:
all observable behaviors of your system
will be depended on by somebody.

• https://en.cppreference.com/w/cpp/compiler_support
• https://docs.microsoft.com/en-us/cpp/overview/visual-cpp-language-conformance
• predefined preprocessor definitions
  • https://sourceforge.net/p/predef/wiki/Home/
  • https://en.cppreference.com/w/cpp/preprocessor/replace#Predefined_macros
  • https://en.cppreference.com/w/cpp/feature_test
  • https://www.boost.org/doc/libs/release/libs/predef/

• Qt Creator
  • Windows Offline Installer includes MinGW gcc
  • https://download.qt.io/
  • https://www.qt.io/offline-installers
• JetBrains CLion
  • https://www.jetbrains.com/clion/
• Microsoft Visual Studio
  • https://visualstudio.microsoft.com/downloads/
• MinGW
  • https://wiki.qt.io/MinGW-64-bit
• CodeLite
  • https://codelite.org/
• embarcardero C++ Builder
  • https://www.embarcadero.com/de/products/cbuilder/starter

• Intel VTune Profiler
  • https://www.intel.com/content/www/us/en/developer/tools/oneapi/vtune-profiler.html
• Linux perf record
  • https://linux.die.net/man/1/perf-record
  • https://perf.wiki.kernel.org/index.php/Main_Page
• https://optick.dev/
• valgrind:
  • https://valgrind.org/docs/manual/manual.html
  • cachegrind
    • https://valgrind.org/docs/manual/cg-manual.html
  • callgrind
    • https://valgrind.org/docs/manual/cl-manual.html