declared variable of type double gets automatically initialized to inf

Question

I am running my code with gcc. I have a function in which I declare a variable X1 which is initialized to 'inf'.

function(double nu, void *params) {
struct func_params *part= (struct func_params *)params;
double result;
*commands*
if (condition){
        double wb,X1;
        printf("inside if X1 %e \n",X1);
    }
return result;

this code is returning "inside if X1 inf". I never had that issue and I didn't change anything to the code...Any idea what it could be?

Using uninitialized variables means that their value is what is in the memory at the time of allocation (which is unpredictable and can vary from one execution to another). — Sianur, Aug 02 '18 at 12:39

score 1 · Answer 1 · answered Aug 02 '18 at 12:39

1

It is Undefined bahavior and your unitialized variable can have any value including inf & NaN.

When you use it you invoke the Undefined Behavior

answered Aug 02 '18 at 12:39

0___________

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Ok I didn't know that this could also include inf & NAN – pulsar_hh Aug 02 '18 at 12:42
why not - it is just sequence of bits. – 0___________ Aug 02 '18 at 12:46

declared variable of type double gets automatically initialized to inf

1 Answers1