[avr-gcc-list] Compiler warning

[David Breeze]

Can any one help!

The code shown below always gives a compiler warning

Compiling Button.c
Button.c: In function `buttonReadPort':
Button.c:123: warning: asm operand 0 probably doesn't match constraints

I have tried various forms of coersion and no coersion for operand 0, the 
result is always the same.

The compiler in use is the winbuild version from AVR Freaks site avr-gcc 3.0.2 
dec 14, 2001.

The code produced is what is required, so am I doing something wrong? or is 
this a compiler bug?

(Sadly I cannot use the provided macros as they now fall foul of our recently 
tightened coding standards).

static __inline__ u8 buttonReadPort(u8 port)
{
    u8  result;
    
    __asm__("in %0,%1" : "=r" ((u8)(result)) : "I" (port) );
    return result;
}

Thanks in advance

David Breeze



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