Re: Dimensions of array parameters

[ludovic dot courtes at inria dot fr (Ludovic Courtès)]

Hi,

Ian Lance Taylor <iant@google.com> skribis:

> ludovic.courtes@inria.fr (Ludovic CourtÃs) writes:
>
>> "Joseph S. Myers" <joseph@codesourcery.com> skribis:
>>
>>> On Fri, 2 Dec 2011, Ludovic CourtÃs wrote:
>>>
>>>> Is there a way array dimension info could be preserved?
>>>
>>> Perhaps you could explain the actual problem you are trying to solve?
>>
>> Iâm just thinking that, if that information were preserved, GCC could do
>> static bound checking and/or generate bound checking code.
>
> The ABI for a C function does not provide any way to pass down the
> dimensions of an array.

I understand.  However, Iâm concerned about keeping the information at
compile-time.  For example:

  extern void foo (int a, int x[a]);
  static void bar (void) {
    int x[123];
    foo (456, x);
  }

Here the compiler could emit a diagnostic in âbarâ.

IOW, ABI restrictions ABI imply that nothing can be done in the body of
âfooâ; however, the information could still used at call sites.

WDYT?

Thanks,
Ludoâ.