Unwanted remove of unused variables with GCC

Mattias Guest #1923514
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Hi,

I have a application where I need to declare a couple of variables in 
RAM but they will not be used in the application. I then use the RAM 
addresses for the variables, to change there values via a communication 
port.

Unfortunately GCC remove the variables if I don't use them, and I don't 
want to add "fake use" like "if(var_name){}"

I don't use any optimizing at the moment, the variables are removed 
anyway.

Is there a way to keep them?

Thanks

/Mattias
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Johann L. #1924543
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I don't quite understand what you are doing... you use the address of a 
variable the variable is used (in general) and the object must not be 
canceled out. Can you give a small example in C to make it clear?

Jörg Wunsch wrote:
> Not sure how a "communication port" could change SRAM data without
> the intervention of code, anyway, what you're probably looking for
> is
>
>
1
__attribute__((used))


AFAIR this helps for functions, not for vars.
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