[deimos]

Originally Posted by nogginthenog

AmigaOS ROM calls work this way via the inlines.

void MyFunc(register int d0 __asm("d0"));

MyFunc(2);

results in:

moveq #2,d0
jsr _MyFunc

Yes, but in this case they don't:

C:/Users/Me/Desktop/AmigaDevelopment/test/test.c:57:38: error: expected ';', ',' or ')' before '__asm'

for the code:

void AquireLock(register BYTE * lock __asm("a0"));

and:

    AquireLock(&tripleBufferedDisplay->displayFlippingLock);

Makes me think there's something missing, either in GCC 8.3 or in my code.

I've worked around this situation by using GCC's extended inline assembly:

    {
        register BYTE * lock asm ("a0") = &tripleBufferedDisplay->displayFlippingLock;
        asm volatile (
            "jsr    _ReleaseLock"
            :
            : "r" (lock)
        );
    }

but that's not an easily maintainable solution.