Re: gcc.c-torture/execute/va-arg-24.c

[Geoffrey Keating <geoffk at apple dot com>]

On Friday, October 10, 2003, at 07:37  AM, Richard Earnshaw wrote:

> This test is bogus.  How can the vector {14,15,16,17} ever compare 
> equal
> to the vector {20,21,22,23} ?

Ugh.  There's another typo.  The answer to your question is "easily, if 
you are comparing 1 byte from them".

I'll make a corrected testcase.

> #include <stdarg.h>
>
> #define vector __attribute__((vector_size(16)))
>
> const vector unsigned int v1 = {10,11,12,13};
> const vector unsigned int v2 = {20,21,22,23};
>
> void foo(int a, ...)
> {
>   va_list args;
>   vector unsigned int v;
>
>   va_start (args, a);
>   v = va_arg (args, vector unsigned int);
>   if (a != 1 || memcmp (&v, &v1, sizeof (v)) != 0)
>     abort ();
>   a = va_arg (args, int);
>   if (a != 2)
>     abort ();
>   v = va_arg (args, vector unsigned int);
>   if (memcmp (&v, &v2, sizeof (v) != 0))
>     abort ();
>   va_end (args);
> }
>
> int main(void)
> {
>   foo (1, (vector unsigned int){10,11,12,13}, 2,
>        (vector unsigned int){14,15,16,17});
>   return 0;
> }