...
| Code Block |
|---|
#include <math.h>
#if defined(math_errhandling) \
&& (math_errhandling & MATH_ERREXCEPT)
#include <fenv.h>
#pragma STDC FENV_ACCESS ON
#endif
/* ... */
#if defined(math_errhandling) \
&& (math_errhandling & MATH_ERREXCEPT)
feclearexcept(FE_ALL_EXCEPT);
#endif
errno = 0;
/* Call the function */
#if !defined(math_errhandling) \
|| (math_errhandling & MATH_ERRNO)
if (errno != 0) {
/* Handle range error */
}
#endif
#if defined(math_errhandling) \
&& (math_errhandling & MATH_ERREXCEPT)
if (fetestexcept(FE_INVALID
| FE_DIVBYZERO
| FE_OVERFLOW
| FE_UNDERFLOW) != 0) {
/* Handle range error */
}
#endif
|
...
| Code Block | ||||
|---|---|---|---|---|
| ||||
#include <math.h>
void func(double x) {
double result;
if (isless(x, 0.0)) {
/* Handle domain error */
}
result = sqrt(x);
} |
| Anchor | ||||
|---|---|---|---|---|
|
Noncompliant Code Example
...
(
...
sinh(), Range Errors)
This noncompliant code example determines the hyperbolic cosine of x:
...
This code may produce a range error if x has a very large magnitude.
Compliant Solution
...
(
...
sinh(), Range Errors)
Because this function has no domain errors but may have range errors, the programmer must detect a range error and act accordingly:
| Code Block | ||||
|---|---|---|---|---|
| ||||
#include <errno.h>
#include <math.h>
#if defined(math_errhandling) \
&& (math_errhandling & MATH_ERREXCEPT)
#include <fenv.h>
#pragma STD FENV_ACCESS ON
#endif
void func(double x) {
double result;
errno = 0;
result = sinh(x);
#if defined(math_errhandling) \
&& (math_errhandling & MATH_ERREXCEPT)
feclearexcept(FE_ALL_EXCEPT);
#endif
#if !defined(math_errhandling) \
|| (math_errhandling & MATH_ERRNO)
if (errno != 0) {
/* Handle range error */
}
#endif
#if defined(math_errhandling) \
&& (math_errhandling & MATH_ERREXCEPT)
if (fetestexcept(FE_INVALID
| FE_DIVBYZERO
| FE_OVERFLOW
| FE_UNDERFLOW) != 0) {
/* Handle range error */
}
#endif
} |
...
| Code Block | ||||
|---|---|---|---|---|
| ||||
#include <errno.h>
#include <math.h>
#if defined(math_errhandling) \
&& (math_errhandling & MATH_ERREXCEPT)
#include <fenv.h>
#pragma STDC FENV_ACCESS ON
#endif
void func(double x, double y) {
#if defined(math_errhandling) \
&& (math_errhandling & MATH_ERREXCEPT)
feclearexcept(FE_ALL_EXCEPT);
#endif
errno = 0;
double result;
if (((x == 0.0f) && islessequal(y, 0.0)) || isless(x, 0.0)) {
/* Handle domain or pole error */
}
result = pow(x, y);
#if !defined(math_errhandling) \
|| (math_errhandling & MATH_ERRNO)
if (errno != 0) {
/* Handle range error */
}
#endif
#if defined(math_errhandling) \
&& (math_errhandling & MATH_ERREXCEPT)
if (fetestexcept(FE_INVALID
| FE_DIVBYZERO
| FE_OVERFLOW
| FE_UNDERFLOW) != 0) {
/* Handle range error */
}
#endif
} |
...
| Code Block | ||||
|---|---|---|---|---|
| ||||
#include <errno.h>
#include <math.h>
#if defined(math_errhandling) \
&& (math_errhandling & MATH_ERREXCEPT)
#include <fenv.h>
#pragma STDC FENV_ACCESS ON
#endif
void func(float x) {
float result;
errno = 0;
result = asin(x);
#if defined(math_errhandling) \
&& (math_errhandling & MATH_ERREXCEPT)
feclearexcept(FE_ALL_EXCEPT);
#endif
#if !defined(math_errhandling) \
|| (math_errhandling & MATH_ERRNO)
if (errno != 0) {
/* Handle range error */
}
#endif
#if defined(math_errhandling) \
&& (math_errhandling & MATH_ERREXCEPT)
if (fetestexcept(FE_INVALID
| FE_DIVBYZERO
| FE_OVERFLOW
| FE_UNDERFLOW) != 0) {
/* Handle range error */
}
#endif
} |
...