The real hard limit is 73 bytes [0], to actually run any code in the executable without segfaulting right away. You can cram about 3 simple syscalls into that limit (e.g., my BGGP4 submission [1], which copies the executable to another file), including the final exit() or exit_group() if you want your program to terminate cleanly. Strings are very costly: I couldn't get a Hello World below 77 bytes.
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The real hard limit is 73 bytes [0], to actually run any code in the executable without segfaulting right away. You can cram about 3 simple syscalls into that limit (e.g., my BGGP4 submission [1], which copies the executable to another file), including the final exit() or exit_group() if you want your program to terminate cleanly. Strings are very costly: I couldn't get a Hello World below 77 bytes.
[0] https://tmpout.sh/3/22.html
[1] https://github.com/binarygolf/BGGP/pull/3/files, assembly at https://gist.github.com/LegionMammal978/347c939def56dcba449c...