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This rule does not apply to demotions of floating-point types on implementations that support signed infinity, such as IEEE 754, as all numbers are representable.

Noncompliant Code Example (

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float to int)

This noncompliant code example leads to undefined behavior if the integral part of f_a cannot be represented as an integer:

void func(float f_a) {
  int i_a;
 
  /* Undefined if the integral part of f_a >= INT_MAX */
  i_a = f_a;
}

Compliant Solution (

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float to int)

This compliant solution assumes that the range of floating-point values of type float is greater than that of an int. (This , as is the case in almost all most implementations. ) Unfortunately, there is no safe way to inquire about this assumption in the code short of already knowing the implementation. Converting INT_MAX to float is a problem on many implementations, resulting in a power of 2, rather than 1 less. 

#include <limits.h>
 
void func(float f_a) {
  int i_a;

  if (f_a >= (float)INT_MAX || f_a < (float)INT_MIN) {
    /* Handle error */
  } else {
    i_a = f_a;
  }
}

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