Reinitialization of same variable

[Orane]

When I reintialize a variable, CL compiler issues the following error.

---- Program ---
int siVar=10 ;
int siVar=10;
---------------------

error C2374: 'siVar' : redefinition; multiple initialization
test.c(1) : see declaration of 'siVar'

Can anyone tell me whether it is as per ANSI C specification.

If yes, could you please give me the snip from ANSI C specification,(ISO/IEC 9899:1999)


Thanks in advance :-)

[ravenspoint]

When I reintialize a variable, CL compiler issues the following error.

---- Program ---
int siVar=10 ;
int siVar=10;
---------------------

error C2374: 'siVar' : redefinition; multiple initialization
test.c(1) : see declaration of 'siVar'

You have told the compiler to store siVar in two different places. It rightly refuses.

Declare the variable, with or without an initiazation, just once. Then you can only change its value.

[JosAH]

You have told the compiler to store siVar in two different places. It rightly refuses.

Declare the variable, with or without an initiazation, just once. Then you can only change its value.

No, that's not how thing work:you can declare a variable as many times as you
want (all declarations should be identical), but you should only define it once.

As the OP did: the variable was defined because of the initializer (list) and then
it was defined again (using an identical initializer (list)).

Check the ANSI/ISO Standard for the distinction between declaration and definition.

Jos

[ravenspoint]

Is that right? I confess I have always been vague about the difference between 'define' and 'declare'

Sorry abut that.

The thing to keep in mind is that when you write something like

int x;

the compiler allocates some memory where it keeps the value of x.

You cannot now tell it to store another variable with the same name somewhere else in memory.

[weaknessforcats]

Is that right? I confess I have always been vague about the difference between 'define' and 'declare'

Define means to allocate memory. So these are definitions:

int data;
 
void fx()
{
    //etc...
}
 

Declare is to assert that something not defined does exist and is vaid to use. These are declarations:

extern int data;
 
void fx();
 
class MyClass
{
    //etc...
};