Dev-C++ 5.11是否支持C++11？编译警告相关技术咨询

First: What's a "Language Standard"? #

You're on the right track, but let's clarify the exact relationship:

• A language standard (like C11, C17) is an official, formal document published by standards bodies (e.g., ISO for C++) that defines:
  • The syntax rules of the language (e.g., how to write a delegating constructor)
  • The semantic behavior of every feature (e.g., exactly how constructor delegation should work)
  • The required standard library components and their interfaces
• The "software implementation" part falls to compilers (like GCC, Clang, MSVC). Compilers take the standard's rules and turn your code into executable machine code. A compiler is said to "support a standard" when it correctly implements all (or most) of the rules defined in that standard document.

So yes, new standards do define new features, but those features only become reliably usable when compilers implement them according to the standard's specs. Your initial thought that it's not just a list of features is spot-on—standards also enforce consistency across different compilers, so your code behaves the same no matter which compliant toolchain you use.

Second: The Delegating Constructor Warning #

Let's break down the warning: [Warning] delegating constructors only available with -std=c++11 or -std=gnu++11

Is this warning serious? #

It's not a fatal error (which is why your code still runs), but it's not something to ignore:

• Your compiler is running in a default mode (usually an older standard like C98 for legacy compatibility) but is "forgiving" and letting you use C11 features anyway. However, this behavior isn't guaranteed—future compiler versions might stop allowing this, or the feature might behave inconsistently compared to the official C++11 spec.
• If you try to compile this code on a different compiler or older toolchain, it might fail entirely without the correct standard flag.

How to fix it? #

You have a few straightforward options:

1. Add the standard flag to your compile command
   • If you're using a terminal, compile your code with:

     g++ your_file.cpp -std=c++11 -o your_program
     

     Or use -gnu++11 instead if you want to use C++11 plus GCC-specific extensions.
2. Use a newer standard version
   • If your compiler supports it (most modern GCC/Clang versions do), use a later standard like C17 or C20—these include all C++11 features, so you'll get the delegation support plus more:

     g++ your_file.cpp -std=c++17 -o your_program
     

3. Update your IDE settings
   • If you're using an IDE (e.g., CLion, Code::Blocks, Visual Studio), find the compiler settings panel and add -std=c++11 (or a newer standard) to the list of compiler flags.
4. Check your compiler version
   • If you're using a very old compiler (GCC before version 4.7, for example), it might not support C++11 at all. In that case, you'll need to upgrade your compiler to a newer version.

内容的提问来源于stack exchange，提问作者DigitaLBullet