float may_be_inf() {
 ...
 return 1.0/0.0;
}
void fpclassify_guard() {
 float x = may_be_inf();
 int y;
 // error, casting possible infinity to int
 y = x; 
 // example 1: easiest to support:
 if (fpclassify(x) != FP_INFINITE) {
 // or "fpclassify(x) == FP_NORMAL"
 y = x;
 }
 // example 2: perhaps slightly harder to support, but guards library already has infra for this:
 switch(x) {
 case FP_NORMAL:
 case FP_SUBNORMAL:
 case FP_ZERO:
 // or, "case FP_INFINITE: break; default:"
 y = x;
 }
 // example 3: this is harder to support but a common pattern:
 int cls = fpclassify(x);
 if (cls != FP_INFINITE) {
 // or "cls == FP_NORMAL || cls == FP_ZERO"
 y = x;
 } 
}