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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: "...the value becomes,indeterminate each time the declaration is reached"
Date: Thu, 07 Feb 2019 10:57:00 -0800
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David Brown <david.brown@hesbynett.no> writes:
[...]
> There are some kinds of UB that could be handled by a more complex
> grammar describing the C language.  The grammar rules of C /could/ have
> precluded invalid multi-byte characters in the source code, or
> converting a pointer to something other than an integer or pointer type.
>  But they don't preclude them.  If they had, then there would be no need
> to call them "undefined behaviour" - the code would simply not be
> syntactically valid C.
[...]

I don't think pointer conversion is an example of what you're talking
about.  Converting a pointer to something other than an integer or
pointer type is a constraint violation.  I don't see how that could be
enforced in the grammar.  Given:

    some_type x = (some_other_type)y;

we can't tell whether the constraint is violated without knowing how
some_time and some_other_type are defined.

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Will write code for food.
void Void(void) { Void(); } /* The recursive call of the void */