Re: [avr-gcc-list] inline assembler problem

[Ewout Boks]

That is the inline asm problem I asked Joerg about yesterday. It is an 
unecessary warning since your code looks perfectly allright.

I believe that it has been solved in post 3.3.1 versions of avr-gcc, so 
update the compiler is your solution.

Ewout


> Date: Mon, 19 Jan 2004 07:20:03 +0100
> From: Matte <address@hidden>
> To: address@hidden
> Subject: Re: [avr-gcc-list] inline assembler problem
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> Hi 
>
> Since some of you wanted to view the whole testprogram in order to help
> me track the error I've struggeling with, I post it here. The compiler
> I'm using is still the avr-gcc-3.3.1. 
> The functions in the code below I did implement in order to have some
> simple functions to learn from. 
>
>
> #include <inttypes.h>
>
> #define PORT_A 0x1B
> #define DDR_A 0x1A
> #define PIN_A 0x19
>
> uint8_t read(const uint8_t adr) {
>   uint8_t p;
>   asm volatile ("in %0, %1" : "=r" (p) : "I" (adr));
>   return p;
> }
>
> uint8_t fastSBI(const uint8_t port, const uint8_t bit) {
>   asm volatile("sbi %0, %1" : : "I" (port), "I" (bit));
> }
>
> int main(void) {
>   uint8_t port_a = PORT_A;
>   uint8_t ddr_a = DDR_A;
>   uint8_t pin = 3;
>   uint8_t data;
>  
>   data = read(port_a);
>   fastSBI(ddr_a, pin);
>   
>   return 0;
> }
>
> When trying to compile this I get the following errors: 
> inlasm.c: In function `read':
> inlasm.c:11: warning: asm operand 1 probably doesn't match constraints
> inlasm.c:11: error: impossible constraint in `asm'
> inlasm.c: In function `fastSBI':
> inlasm.c:17: warning: asm operand 0 probably doesn't match constraints
> inlasm.c:17: warning: asm operand 1 probably doesn't match constraints