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How to type braces for computed gotos (was: Best "simple" C Compiler I've ever seen)

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On Sunday, May 4, 2014 8:23:05 PM UTC-5, andrewc...@gmail.com wrote:
> https://github.com/rui314/8cc
> Self hosting, extremely well written, and seems geared towards simple
> but complete code rather than being a complicated monolith.

On that count: usually when I redo a source (reformat, reanalyze the math,
make more effective use of the language, etc.) it comes out to 50% reduction
by lines 30% by bytes; which is consistent across thousands of source files.

The only exceptions I've encountered to date are stuff I earlier reduced (30%
by lines if it made use of an earlier dialect of the language), stuff from
AT&T (which does not reduce much, e.g. CFront) and the source for this
compiler.

So by that count, it's well-written and compact.

There is one feature the compiler tests for that I assume the language also
has in it that I haven't seen much of before: the computed goto. What's I
don't quite understand how the branches are being typed. A computed goto
inside a void routine has the branches typed (void *), with the individual
items accessed in effect as references to (void *).

The branches are essentially continuations. So the question here is how are
continuations being typed. From the example used in the distribution, either
(A) all continuations are typed (void *) or they are being typed (T *) when
they occur inside a function that returns type T.
[That's an extension. In standard C, you can only goto a label. -John
Perhaps it's similar to this GCC extension
https://gcc.gnu.org/onlinedocs/gcc/Labels-as-Values.html#Labels-as-Values]

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Best "simple" C Compiler I've ever seen andrewchamberss@gmail.com - 2014-05-04 18:23 -0700
  Re: Best "simple" C Compiler I've ever seen federation2005@netzero.com - 2014-06-30 12:42 -0700
  How to type braces for computed gotos (was: Best "simple" C Compiler I've ever seen) federation2005@netzero.com - 2014-07-18 14:44 -0700
    Re: How to type braces for computed gotos glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-07-19 02:21 +0000
      Re: How to type braces for computed gotos Ivan Godard <ivan@ootbcomp.com> - 2014-07-18 21:59 -0700
      Re: How to type braces for computed gotos federation2005@netzero.com - 2014-07-21 10:32 -0700
    Re: How to type braces for computed gotos (was: Best "simple" C Compiler I've ever seen) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-07-21 11:45 +0000
      Re: How to type braces for computed gotos glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-07-21 16:19 +0000
      Re: How to type braces for computed gotos wclodius@earthlink.net (William Clodius) - 2014-07-21 21:44 -0600
        Re: How to type braces for computed gotos glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-07-23 00:35 +0000
          Re: How to type braces for computed gotos wclodius@earthlink.net (William Clodius) - 2014-07-22 22:36 -0600
            Re: How to type braces for computed gotos anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-07-25 22:38 -0400

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