floating exception using icc compiler
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by Hristo
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Published on 2010-05-02T04:56:04Z
Indexed on
2010/05/02
5:07 UTC
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I'm compiling my code via the following command:
icc -ltbb test.cxx -o test
Then when I run the program:
time ./mp6 100 > output.modified
Floating exception
4.871u 0.405s 0:05.28 99.8% 0+0k 0+0io 0pf+0w
I get a "Floating exception". This following is code in C++ that I had before the exception and after:
// before
if (j < E[i]) {
temp += foo(0, trr[i], ex[i+j*N]);
}
// after
temp += (j < E[i])*foo(0, trr[i], ex[i+j*N]);
This is boolean algebra... so (j < E[i]) is either going to be a 0 or a 1 so the multiplication would result either in 0 or the foo() result. I don't see why this would cause a floating exception. This is what foo() does:
int foo(int s, int t, int e) {
switch(s % 4) {
case 0:
return abs(t - e)/e;
case 1:
return (t == e) ? 0 : 1;
case 2:
return (t < e) ? 5 : (t - e)/t;
case 3:
return abs(t - e)/t;
}
return 0;
}
foo() isn't a function I wrote so I'm not too sure as to what it does... but I don't think the problem is with the function foo(). Is there something about boolean algebra that I don't understand or something that works differently in C++ than I know of? Any ideas why this causes an exception?
Thanks, Hristo
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