🚀 go-pugleaf

In article <9209040741.AA16120@enet-gw.pa.dec.com> diamond@jit081.enet.dec.com (04-Sep-1992 1639) writes:
>In article <1992Sep4.015335.3612@thinkage.on.ca> dat@thinkage.on.ca (David Adrien Tanguay) writes:
>>diamond@jit081.enet.dec.com (03-Sep-1992 1325) writes:
>>>In article <PINKAS.92Sep2173635@skywalker.intel.com> pinkas@skywalker.intel.com (Israel Pinkas) writes:
>>>> The variable length struct is a hack.  There is nothing in the language that
>>>> prevents the compiler from performing bounds checking on accesses to name.
>>> Bounds checking is not allowed to affect output of a valid but ugly program.
>> I had the impression that the last time it came up here the conclusion was
>> that this trick was not sanctioned[...]  3.3.6 "Additive Operators"
>> says that you aren't guaranteed to go past the end of an array object,
> No (though it was the conclusion of some others) and yes, respectively.
> You can't go past the end of an array object.  But if malloc() or some other
> variable has defined the end of the actual array object, then the + operator
> can get you that far, regardless of the declared type that some other array
> variable had before getting flattened to a pointer.

But there is an intepretation that says that, given

    int a [5][5];

the access "a [1][6]" is illegal, because it goes past the bounds of the
array "a [1]". In other words, the declared type of the array does
restrict what can happen to a pointer derived from it.
-- 
Clive D.W. Feather     | IXI Limited         | If you lie to the compiler,
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