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According to section 7.14.1.1 (signals) of the C standard; returning from a SIGSEGV, SIGILL, or SIGFPE signal handler is undefined behavior:

If and when the function returns, if the value of sig is SIGFPE, SIGILL, SIGSEGV, or any other implementation-defined value corresponding to a computational exception, the behavior is undefined; otherwise the program will resume execution at the point it was interrupted.

Noncompliant Code Example

In this non-compliant noncompliant code example, if the given user input is '0', the division operation causes results in a SIGFPE signal to be being sent to the program.

volatile sig_atomic_t denom;

void sighandle(int s){
  /* Fix the offending volatile */                   
  if (denom == 0) {
    denom == 1;
  }
  /* Everything is ok */
  return;
}

int main(int argc, char *argv[]){
  if (argc < 2) {
    return 0;
  }

  int result = 0;
    denom denom = atoi(argv[1]);

  signal(SIGFPE,(*sighandle));

  result = 100/denom;
  return 0;
}

void sighandle(int s){
  /* Fix the offending volatile */                   
  if(denom == 0)
    denom == 1;
  /* Everything is ok */
  return;
}

The above noncompliant code example will loop infinitely on most systems when supplied with 0 as an argument.
This illustrates that even when a SIGFPE handler attempts to fix the error condition while obeying all other rules of signal handling, the behavior may not be as expected.

...

void sighandle(int s){
  /* No recovery */
  abort();
}

The only portably safe way to leave a SIGFPE, SIGILL, or SIGSEGV handler is through abort() or _exit /_Exit().

Risk Assessment

Attempting to handle SIGSEGV/SIGILL/or SIGFPE signals is rare.

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