[dgplug-users] A trivial C concept problem

[Sumit Chakraborty]

On Fri, Jul 3, 2009 at 10:24 AM, Shakthi Kannan <shakthimaan at gmail.com>wrote:

> Hi,
>
> --- On Fri, Jul 3, 2009 at 9:15 AM, abhishek
> sharma<emote2abhishek at gmail.com> wrote:
> |  int *p=c;                                        //For this code
> | gcc compiles normally without any error or problem
> \--
>
> This is correct.
>
> ---
> |  int c[5]={1,2,3,4,5};
> |
> |  int  *p;
> |
> |  *p=c;    //GCC gives a typecast
> \--
>
> It should be 'p = c'. On the left-hand side of the assignment there
> should be an address or LVALUE. On the right-hand side of the
> assignment you should have a value or RVALUE. When you do *p on the
> left-hand side of the assignment, you are dereferencing the address or
> pointer, to get a RVALUE. Hence, the error.
>
> 1. Don't use // comments in C coding style.
>
> 2. Initialize your pointer variables, or assign NULL to them.
>
>  int *p = NULL;
>
> SK
>
> --
>
I agree with Shakthi.

When you are doing int *p=c, the compiler does two things:

1. int *p   //declare the variable p as type int *
2. p=c     // store the base address of the variable a

So instead of *p=c, your code should feature p=c.

Thanks and Regards
Sumit Chakraborty
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