c++ compiler not working after macOS sequoia update

It’s probably just you |-:

I have a post that covers this general topic: Investigating Third-Party IDE Integration Problems. Please run through that process and write back if you hit a snag with the Apple side of this.

Share and Enjoy
—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"

I am seeing this on my Mac which I've just upgraded to Sequoia:

$ cat hello.cpp
#include <iostream>
int main() {
  std::cout << "Hello, world!!\n";
}
$ clang hello.cpp
hello.cpp:1:10: fatal error: 'iostream' file not found
    1 | #include <iostream>
      |          ^~~~~~~~~~
1 error generated.

I have one Mac with Sonoma where this works; the above error is from my other Mac where I just installed Sequoia. I do C++ development (on multiple platforms) for a living -- the only change is my having installed Sequoia on my one Mac, whereat a hello-world C++ program no longer compiles.

After uninstall and reinstall of xcode (version 2409 reported before & after) I can compile hello-world using clang++ and g++

I am also getting same error test.cc:1:10: fatal error: 'iostream' file not found 1 | #include <iostream> | ^~~~~~~~~~ 1 error generated. make: *** [test] Error 1 while compiling from terminal, but Xcode is working

Problem solved after upgrading os to latest version

https://github.com/ggerganov/llama.cpp/issues/9575

At the very bottom someone says to do

sudo rm -rf /Library/Developer/CommandLineTools/
xcode-select --install

and it worked for me!!!! If this is a bad idea dont do it obviously im a novice dev