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by chvid5 hours ago |
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upvoteby falcor844 hours ago|
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> literally a text book task

Generating a 99% compliant C compiler is not a textbook task in any university I've ever heard of. There's a vast difference between a toy compiler and one that can actually compile Linux and Doom.

From a bit of research now, there are only three other compilers that can compile an unmodified Linux kernel: GCC, Clang/LLVM and Intel's oneAPI. I can't find any other compiler implementation that came close.

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upvoteby cv50054 hours ago|
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That's because you need to implement a bunch of gcc-specific behavior that linux relies on. A 100% standards compliant c23 compiler can't compile linux.
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upvoteby falcor841 hours ago|
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Ok, yes, that's true, though my understanding is that it's not the GCC is not compliant, but rather that it includes extensions beyond the standard, which is allowed by the standard, which says (in section 4. Conformance):

> A conforming implementation may have extensions (including additional library functions), provided they do not alter the behavior of any strictly conforming program

Anyway, this just makes Claude's achievement here more impressive, right?

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upvoteby anematode4 hours ago|
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A simple C89 compiler is a textbook task; a GCC-compatible compiler targeting multiple architectures that can pass 99% of the GCC torture test suite is absolutely not.
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upvoteby blibble1 hours ago|
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indeed

building a working C compiler from scratch is literally in my "teach yourself C in 24 hours" book from 30 years ago

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upvoteby simonw1 hours ago|
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Which book was that? Sounds excellent.

Might have been Compiler Design in C from 1990. Looks like that's available for free now: https://holub.com/compiler/

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upvoteby wmf4 hours ago|
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This has multiple backends and a long tail of C extensions that are not in the textbook.
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