Re: [PATCH v1] Remove 'restrict' from 'nptr' in strtol(3)-like functions

[LIU Hao <lh_mouse@126.com>]

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在 2024-07-05 23:23, Alejandro Colomar via Gcc 写道:
> Hi Martin,
> 
> On Fri, Jul 05, 2024 at 05:02:15PM GMT, Martin Uecker wrote:
>>> But when the thing gets non-trivial, as in strtol(3), GCC misses the
>>> -Wrestrict diagnostic, as reported in

A pointer to `char` can alias any object, so in theory one could write code that looks like below. 
This piece of code is probably nonsense, but it illustrates the exact necessity of the `restrict` 
qualifiers:

    char*
    dumb(char* p)
      {
        strtol((const char*) &p, &p, 0);
        return p;
      }

    // warning: passing argument 2 to 'restrict'-qualified parameter
    // aliases with argument 1






-- 
Best regards,
LIU Hao


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