Both GCC and Clang generate strange/inefficient code
Summary
A blog post reports surprising assembly outputs when compiling a simple C++ function that checks if a std::array contains only zeros. The author compares GCC and Clang with array sizes 1, 2, and 3, noting unusual instruction sequences and unnecessary stack initialization in some cases. The piece argues that compiler optimizations can be non-intuitive and that trivial code changes can affect generated code, highlighting pitfalls when trusting compiler output for performance.