float_t, double_t
Header: <math.h>
The types float_t and double_t are floating types at least as wide as float and double, respectively, and such that double_t is at least as wide as float_t. The value of FLT_EVAL_METHOD determines the types of float_t and double_t.
# Declarations
typedef /* implementation-defined */ float_t
(since C99)
typedef /* implementation-defined */ double_t
(since C99)
# Example
#include <float.h>
#include <math.h>
#include <stdio.h>
#define SHOW(expr) printf("%s = %d\n", #expr, (int)(expr))
int main()
{
SHOW(FLT_EVAL_METHOD);
SHOW(sizeof(float));
SHOW(sizeof(float_t));
SHOW(sizeof(double));
SHOW(sizeof(double_t));
}