Cannot see local variables

Please, be more specific.
Local variables can not be seen (because they do not exist) before you step to the point of their creation. Static variables, on the other hand, have static linkage and exist forever (but they can be seen only in the scope of their function).

For example:

void foo()
{
    <some code>; // <-- all static variables from this function are already visible

    static int a; // <-- despite the fact they are created on this line

    <some code alse>;

    int b; // <-- local variable b start its existence only from this line
           // and can be seen only from here
}

If that's the case than it's completely normal.

Please, be more specific.
Local variables can not be seen (because they do not exist) before you step to the point of their creation. Static variables, on the other hand, have static linkage and exist forever (but they can be seen only in the scope of their function).

For example:

void foo()
{
    <some code>; // <-- all static variables from this function are already visible

    static int a; // <-- despite the fact they are created on this line

    <some code alse>;

    int b; // <-- local variable b start its existence only from this line
           // and can be seen only from here
}

If that's the case than it's completely normal.

Thank you for your answer. When you ask me the optimization level I was using, I started checking and reading about it and realised that there was the problem. I'm using now level 0 o level 1 for debugging purposes

Add "volatile" on local variable declaration. It is better than using "static".

AddZulkifli Sulton volatile is not "better" than static, it's just a completely different keyword with completely different purpose.

I guess he meant "a better solution to this problem".  Using static will semantically change the code in ways that may change the behaviour of the code, while volatile will not.  It is not however clear that volatile will solve the problem.

The problem has quite certainly become non-existant at some point during the 5 years that have passed since this thread went to sleep...

And that's assuming that there ever was an actual problem to speak of, rather than a lack of understanding of the language.