[llvm-dev] different output with fast-math flag

[sangeeta chowdhary via llvm-dev]

Why the output is different for this below program when compiled using
clang with fast-math optimization

#include<stdio.h>


int main() {

  double d = 1.0;

  double max = 1.79769e+308;


  d /= max;

  printf("d:%e:\n", d);

  d *= max;

  printf("d:%e:\n", d);

  return 0;

}


prints 0 with fast math but 1 without fast math.
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