Re: Where is a static variable stored?

"Jack" <junw2000@xxxxxxxxx> wrote
I think for a static variable defined out of any functions, i.e., it is
a global variable, it is located in the data segment of the program.
How about a static variable defined within a function? it is a local
variable. Is it located at the stack?

A static local variable is basically a global which is only visible within
one function.
That is a contradiction in terms, but it is how the compiler will treat it
under the bonnet.

As for data segment, only some OSes have such things. When the program
loads, memory does need to be reserved for all the global variables,
including the static locals, which is why you can think of them as local
globals.

Incidentally this has an important effect. Let's say we need 1000 xyz
coordinates

/* dangerous, may overflow stack if you are not careful */
void foo()
{
double coords[1000][3];
}

/* safe, memory will be allocated at load time. But gobbles resources for
other functions */
void foo()
{
static double coords[1000][3];
}
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Relevant Pages

  • Re: Localized Parameter Directive?
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  • Re: A Brief Look at History
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