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How I wrote a self-hosting C compiler in 40 days

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429 points rui314 | 1 comments | 14 Dec 15 14:07 UTC | HN request time: 0.001s | source
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peter303 ◴[14 Dec 15 16:36 UTC] No.10732006[source]▶
Long ago UNIX had compiler writing tools like yacc and lex. I wonder if they are useful for exercises like this.
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nly ◴[14 Dec 15 17:03 UTC] No.10732219[source]▶
They might, although no production quality C or C++ compiler uses anything other than a hand-rolled recursive descent parser, afaik.

The lex, parse and AST directories in Clangs source tree are ~100,000 LOC combined, and all hand-written.

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1. alricb ◴[15 Dec 15 03:36 UTC] No.10735743[source]▶
Not now, no, but back in the 4.0 days (2005) GCC still used a yacc/bison parser for C; it had switched to a hand written parser for C++. The C++ yacc parser was still in use as of GCC 3.3 (2003).