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/************************************************************************
*
* 18.limits.traps.stdcxx-624.cpp - regression test for STDCXX-624
*
* $Id:$
*
***************************************************************************
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed
* with this work for additional information regarding copyright
* ownership. The ASF licenses this file to you under the Apache
* License, Version 2.0 (the "License"); you may not use this file
* except in compliance with the License. You may obtain a copy of
* the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
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* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
* implied. See the License for the specific language governing
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**************************************************************************/
#include <cassert> // for assert()
#include <csignal> // for SIGFPE and signal()
#include <cstdlib> // for strtod()
#include <limits> // for numeric_limits
char digits[] = " +0.?23456789e+01";
volatile int result;
extern "C" {
void handle_FPE (int)
{
// if we get here (presumably in response to SIGFPE triggered
// by a trap in integer arithmetic) verify that numeric_limits
// traps is non-zero and successfuly exit the process
assert (std::numeric_limits<int>::traps);
std::exit (0);
}
} // extern "C"
int main ()
{
// prevent clever optimizers from figuring out that (zero == 0)
digits [4] = '0';
const int zero = (int)std::strtod (digits, 0);
// compute a non-zero integer value
digits [4] = '1';
const int non_zero = (int)std::strtod (digits, 0);
// set up a handler for the FPE signal only when traps is true
// otherwise expect to be able to perform integer arithmetic
// without a signal
if (std::numeric_limits<int>::traps)
std::signal (SIGFPE, handle_FPE);
// if this traps (generates SIGFPE), verify (in the signal handler)
// that integer arithmetic is expected to trap
result = non_zero / zero;
result += non_zero % zero;
// if we get this far, verify that integer arithmetic is known not
// to trap
assert (!std::numeric_limits<int>::traps);
(void)&result;
return 0;
}