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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: 0.214s | source
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pagade ◴[14 Dec 15 17:30 UTC] No.10732420[source]▶
Anyone tried using it? How do I use it to generate executable (as per the code it should fork the 'as')?

Getting following error: [ERROR] main.c:144: (null): One of -a, -c, -E or -S must be specified

-c, -E and -S are working fine. Couldn't figure out from code what -a does.

replies(1): >>10733833 #
1. hundchenkatze ◴[14 Dec 15 21:01 UTC] No.10733833[source]▶
Have you tried -o to specify the output file?

As for -a it doesn't look like -a is actually handled in parseopt, through process of elimination it looks like -E sets cpponly, -c sets dontlink, and -S sets dumpasm. So from main.c:143 if you don't set any of those, dumpast needs to be true, and the only way I see that getting set to true is by using this flag '-fdump-ast'

From this commit[0] it looks like -a was removed, but usage docs and error messages weren't updated.

[0]https://github.com/rui314/8cc/commit/614f6e7b643333b9baaf8fb...

Edit: adding link to relevant commit.