Here's a simple C++ program: cpp #include stdio.h int main() { printf("Hello world\n"); return 0; } On my M1 Macbook air, I can compile, run, and debug this program successfully: bash % clang++ hello.cpp -g % ./a.out Hello world % lldb a.out (lldb) target create "a.out" Current executable set to '/Users/sam/build/a.out' (x86_64). (lldb) run Process 55681 launched: '/Users/sam/build/a.out' (x86_64) Hello world Process 55681 exited with status = 0 (0x00000000) When adding -arch arm64, it builds and runs, as expected: bash % clang++ hello.cpp -g -arch arm64 % ./a.out Hello world But debugging seems to fail: bash % lldb a.out (lldb) target create "a.out" Current executable set to '/Users/sam/build/a.out' (arm64). (lldb) run error: process exited with status -1 (attach failed ((os/kern) invalid argument)) Is there anything special I need to do to get lldb to work with an executable compiled with -arch arm64? Macbook Air (M1, 2020) Big Sur 11.0.1 bash % clang++ --version Apple clang version 12.0.0 (clang-1200.0.32.29) Target: x86_64-apple-darwin20.1.0 Thread model: posix InstalledDir: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin bash % lldb --version lldb-1200.0.44.2 Apple Swift version 5.3.2 (swiftlang-1200.0.45 clang-1200.0.32.28)