Re: [PATCH 03/34] rs6000: Add the rest of the [altivec] stanza to the builtins file

[Bill Schmidt via Gcc-patches]

On 8/9/21 6:44 PM, Segher Boessenkool wrote:

This is not a documented GCC extension either, and it might even
conflict with the existing void * extension (allowing arithmetic on it,
by defining sizeof(void)).  In either case it is not currently defined.

I'm not sure how you get to this, but all we're doing here is standard C.

x.c:

char
foo (const void *x)
{
  const char *y = (const char *) x;
  return *y;
}

y.c:

void
foo (const void *x, char c)
{
  const char *y = (const char *) x;
  *y = c;
}

wschmidt@rain6p1:~/src$ gcc -c x.c
wschmidt@rain6p1:~/src$ gcc -c y.c
y.c: In function 'foo':
y.c:5:6: error: assignment of read-only location '*y'
   *y = c;
      ^
wschmidt@rain6p1:~/src$