Can't build clang and libc on macOS?

[fhahn]

@RobNik

I have an Intel MacBook running macOS 13.1.

Moments before I had successfully built it, using the same commands but without the “libc” in the list of runtimes. I tried adding the libc because I couldn’t compile a “helloworld”.

> ~/Dev/llvm-project/build/bin/clang main.c
main.c:1:10: fatal error: 'stdio.h' file not found
#include <stdio.h>

On macOS, you need to specify -isysroot to tell clang where to look for the system headers. You can get the sys root path for macOS (e.g. xcode - How to get the path of latest SDK available on Mac - Stack Overflow)

You should be able to use clang without needing to build libc by doing something like:

clang -isysroot `xcrun -sdk macosx --show-sdk-path` main.c