How to enable C++17 on Mac?

Question

I am able to update gcc on Linux to get -std=c++17 but cannot do the same on Mac. Is there a version of Clang I can update to or some other alternative to get C++17 on my Mac? Please help. Thanks.

Answer 1

On my 10.11 El Capitan, Xcode 7.3.1, clang has been updated to:

Apple LLVM version 7.3.0 (clang-703.0.31)

which is almost equivalent to llvm version 3.8. clang++ hasn't -std=c++17 option, but -std=c++1z, working well at present, though only supporting some features of C++1z.

For gcc, you can install a very new one by:

brew install gcc --HEAD

which will install gcc-6.1 now, (2016.8). This gcc has limited support for C++17 and can be enabled by -std=c++17.

---

some update:

The corresponding llvm version of Apple's clang is not clear recently, should be 3.9+ or 4+. Check this wiki page for more information.

brew install gcc --HEAD should always work for mac/homebrew, and give you the cutting edge gnu gcc with many experimental features. On the other hand, normal brew install gcc should install a gcc supporting most c++17 features now.

For the language standard argument, try -std=c++17 and -std=c++1z for different compilers, one of them should work.

Answer 2

You can install gcc from sources (it's not complex at all) if there are some complications with the repositories.

Installation process for mac os X, and here it is for linux. Hope it helps.

Answer 3

Maybe you should install xcode command tool using:

xcode-select --install

Answer 4

The v17 standard is now offered by default with Xcode 10, offering both standard, and variant flavors.

via Build Settings:

CLANG_CXX_LANGUAGE_STANDARD : C++17/GNU++17

CLI:

-std=c++17

-std=gnu++17