> It seems you have to build with a special flag that tells GCC to put a nop at the start of each function. BTW - llvm+clang support a similar feature called "

> It seems you have to build with a special flag that tells GCC to put a nop at the start of each function. BTW - llvm+clang support a similar feature called "X-ray" [1]. It's intended to allow for patching (and unpatching!) these entry/exit points at runtime, with calls to specific tracing / black box facilities or whatever your favorite logging mechanism might be. And it's not limited to x86_64. [1] https://llvm.org/docs/XRay.html https://llvm.org/docs/XRay.html