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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: Abstract Syntax Tree for C programs
Date: Thu, 13 Jun 2019 02:17:59 -0700
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Keith Thompson <kst-u@mib.org> writes:

> Tim Rentsch <tr.17687@z991.linuxsc.com> writes:
>
>> James Kuyper <jameskuyper@alumni.caltech.edu> writes:
>
> [...]
>
>>> As a result, this is actually easily diagnosable at compile time, and
>>> thus I would have expected it to be a constraint violation - which
>>> leaves me wondering why it isn't.
>
> [Context:  "this" is a cast of a void* value to a function pointer type
> or vice versa.]
>
>> The Rationale document says this:
>>
>>   Consequences of the treatment of pointer types in the
>>   Standard include:
>
> [...]
>
>>     * Even with an explicit cast, it is invalid to convert a
>>       function pointer to an object pointer or a pointer to
>>       void, or vice versa.
>
> [...]
>
>> Note the third-to-last item.  It seems clear the authors intended
>> that converting between function pointer types and object pointer
>> types is not just undefined behavior but simply never allowed in
>> accepted C code.

I guess I should make an explicit statement here.  I take Keith
at his (earlier) word that he has put me in his killfile, and
hence do not assume he will read my postings.  In cases where I
do post a followup to a newsgroup item from Keith, my posting is
meant for the benefit of any other readers that may be interested.

> [...]
>
> (A personal note:  Tim, you're still in my killfile, but that fact
> doesn't place any obligations on me.)

I take this statement to mean Keith is not interested in having a
dialog on the subject, and so I will not comment further.