Самое нужное нововведение C23 так и не добавили.

6.10.4 Binary resource inclusion
...
EXAMPLE 1 Placing a small image resource.

#include <stddef.h>
void have_you_any_wool(const unsigned char*, size_t);
int main (int, char*[]) {
      static const unsigned char baa_baa[] = {
#embed "black_sheep.ico"
      };
      have_you_any_wool(baa_baa, sizeof(baa_baa));
      return 0;
}