Comment by icedchai

21 days ago

Yep. Building a working C compiler that compiles Linux is an impossible task for all but the top 1% of developers. And the ones that could do it have better things to do, plus they’d want a lot more than 20K for the trouble.

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icedchai

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vbezhenar  21 days ago

What's so hard about it? Compiler construction is well researched topic and taught in the universities. I made toy language compiler as a student. May be I'm underestimating this task, but I think that I can build some simple C compiler which will output trivial assembly. Given my salary of $2500, that would probably take me around a year, so that's pretty close LoL.

  • cma  20 days ago

    You can one shot prompt a toy C compiler. Getting one that can compile Linux in a bootable way is significantly harder.

    • f1shy  18 days ago

      Everybody talks as Linux is the most difficult thing to compile in the world. The reality is that linux is well written and designed with portability with crappy compilers in mind from the beginning.

      Also, the booting part, as stated some times, is discutable.

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viraptor  20 days ago

It's a bit more nuanced. You can build a simple compiler without too many issues. But once you want it to do optimisations, flow control protection, good and fast register allocation, inling, autovectoriasation, etc. that's going to take a multiples of the original time.

dgacmu  20 days ago

Some of the hardest parts of the compiler are optimization and clear error handling/reporting. If you forego those - because you're testing against a codebase that is already free of things that break compilation and have no particular performance requirements for the generated code - it's a substantially simpler task.

  • f1shy  18 days ago

    Making a basic C compiler, without much error/warn detection and/or optimizations, is as a matter if fact no so difficult. In many Universities is a semester project for 2 to 3 students.

rezonant  20 days ago

> Building a working C compiler ... is an impossible task

I think you might be thinking of C++

  • icedchai  20 days ago

    I’m not. I’ve been working with C on and off for 30 years. Linux requires GNU extensions beyond standard C. Once you get the basics done, there’s still a lot more work to do. Compiling a trivial program might work. But you’ll hit an edge case or 50 in the millions of lines in Linux.

    I also should’ve qualified my message with “in 2 weeks”, or even “in 2 months.” Given more time it’s obviously possible for more people.

rhubarbtree  21 days ago

Interesting, why impossible? We studied compiler construction at uni. I might have to dig out a few books, but I’m confident I could write one. I can’t imagine anyone on my course of 120 nerds being unable to do this.

  • menaerus  21 days ago

    You are underestimating the complexity of the task so do other people on the thread. It's not trivial to implement a working C compiler very much so to implement the one that proves its worth by successfully compiling one of the largest open-source code repositories ever, which btw is not even a plain ISO C dialect.

    • f1shy  18 days ago

      They did bot compile the whole linux, mind you, just an absolute minimal kernel.

      Doing a real compiler to be used by humans is difficult. Doing a compiler that “gets the thing done” is a different thing.

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