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According to Section 7.14.1.1 (signals) of the C standard [ISO/IEC 9899:2011], 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.

Furthermore, SIGFPE may not be caught for a significant amount significant number of instructions after the floating-point instruction that creates it.

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#include<signal.h>
#include<stddef.h>
#include<stdlib.h>

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[]){
  int result = 0;
    
  if (argc < 2) {
    return 0;
  }
  denom = (int)strtol(argv[1], (char **)NULL, 10);
    
  signal(SIGFPE,(*sighandle));

  result = 100/denom;
  return 0;
}

The noncompliant code example will loop infinitely on input 0 when compiled with GCC 4.3 or GCC 3.4. This  It illustrates that even when a SIGFPE handler attempts to fix the error condition while obeying all other rules of signal handling, the program still does not behave as expected.

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#include<signal.h>
#include<stddef.h>
#include<stdlib.h>

volatile sig_atomic_t denom;

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

int main(int argc, char *argv[]){
  int result = 0;
    
  if (argc < 2) {
    return 0;
  }
  denom = (int)strtol(argv[1], (char **)NULL, 10);
    
  signal(SIGFPE,(*sighandle));

  result = 100/denom;
  return 0;
}

...

Related Guidelines

ISO/IEC 9899:19992011 Section 7.14.1.1, "The signal function"

Bibliography

http://technopark02.blogspot.com/2005/10/handling-sigfpe.html

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