Is __builtin_choose_expr supposed to suppress type errors?

[Florian Weimer <fweimer at redhat dot com>]

The documentation only mentions that syntax errors may be reported for 
the non-chosen branch.

Consider this example:

struct dynarray_int { int a; };
struct dynarray_str { char * a; };

int dynarray_int_call (struct dynarray_int *);
int dynarray_str_call (struct dynarray_str *);

#define GENERIC(dyn) __builtin_choose_expr        \
  (__builtin_types_compatible_p                         \
     (__typeof__ (dyn), struct dynarray_int *),         \
   dynarray_int_call (dyn), dynarray_str_call (dyn))

void
f (void)
{
  {
    struct dynarray_int dyn;
    GENERIC (&dyn);
  }
  {
    struct dynarray_str dyn;
    GENERIC (&dyn);
  }
}

It results in this (with a somewhat dated version of GCC 7):

choose.c: In function ‘f’:
choose.c:17:14: warning: passing argument 1 of ‘dynarray_str_call’ from 
incompatible pointer type [-Wincompatible-pointer-types]
     GENERIC (&dyn);
              ^
choose.c:10:48: note: in definition of macro ‘GENERIC’
    dynarray_int_call (dyn), dynarray_str_call (dyn))
                                                ^~~
choose.c:5:5: note: expected ‘struct dynarray_str *’ but argument is of 
type ‘struct dynarray_int *’
 int dynarray_str_call (struct dynarray_str *);
     ^~~~~~~~~~~~~~~~~
choose.c:21:14: warning: passing argument 1 of ‘dynarray_int_call’ from 
incompatible pointer type [-Wincompatible-pointer-types]
     GENERIC (&dyn);
              ^
choose.c:10:23: note: in definition of macro ‘GENERIC’
    dynarray_int_call (dyn), dynarray_str_call (dyn))
                       ^~~
choose.c:4:5: note: expected ‘struct dynarray_int *’ but argument is of 
type ‘struct dynarray_str *’
 int dynarray_int_call (struct dynarray_int *);
     ^~~~~~~~~~~~~~~~~

I suppose I can add casts to void * to get rid of the warning in this 
case, but it's still a bit annoying.  I would rather not override type 
warnings for the actually chosen branch.  Is there any way to do this?

Thanks,
Florian