builtin_types_compatible.c [plain text]
extern int funcInt(int);
extern float funcFloat(float);
extern double funcDouble(double);
#define func(expr) \
do { \
typeof(expr) tmp; \
if (__builtin_types_compatible_p(typeof(expr), int)) funcInt(tmp); \
else if (__builtin_types_compatible_p(typeof(expr), float)) funcFloat(tmp); \
else if (__builtin_types_compatible_p(typeof(expr), double)) funcDouble(tmp); \
} while (0)
#define func_choose(expr) \
__builtin_choose_expr(__builtin_types_compatible_p(typeof(expr), int), funcInt(expr), \
__builtin_choose_expr(__builtin_types_compatible_p(typeof(expr), float), funcFloat(expr), \
__builtin_choose_expr(__builtin_types_compatible_p(typeof(expr), double), funcDouble(expr), (void)0)))
static void test()
{
int a;
float b;
double d;
func(a);
func(b);
func(d);
a = func_choose(a);
b = func_choose(b);
d = func_choose(d);
int c;
struct xx { int a; } x, y;
c = __builtin_choose_expr(a+3-7, b, x); c = __builtin_choose_expr(0, b, x); c = __builtin_choose_expr(5+3-7, b, x);
y = __builtin_choose_expr(4+3-7, b, x);
}