stdc_leading_zeros_ui
return (stdc_leading_zeros_ui(~ui));
return (stdc_leading_zeros_ui(ui) + 1);
.so_ui = stdc_leading_zeros_ui,
char(*)[4]: stdc_leading_zeros_ui(val), \
extern unsigned int stdc_leading_zeros_ui(unsigned int) _C23_UNSEQ_ATTR;