__sync_val_fetch_and_add未定义

[yinghaoyu]

我把Atomic.h单独拿出来测试， 提示‘__sync_val_fetch_and_add’ was not declared in this scope; did you mean ‘__sync_fetch_and_add’?
请问为何？g++9.4.0

[chenshuo]

What's the output of g++ -v?

On Debian 11 x86-64, works fine for me:

[~/muduo]$ g++ muduo/base/tests/Atomic_unittest.cc -I . -Wall
[~/muduo]$ ./a.out

[yinghaoyu]

Thanks for your patience & reading.
It's all my fault, as __sync_fetch_and_add is the right bulid-in function.