Re: Segfault in fbcmap.c => Compiler bug?

[Haavard Skinnemoen]

Alex Raimondi wrote:
> 			if (transp) 
> 				htransp = *transp++;
> 
> 
> The segfault happens at the if (transp) statment.
> 
> Now to the strange thing, which makes me guess this may be a problem related to a compiler bug:
> 
> When I change the if statment to:
> 
> 			if (transp) {
> 				printk("e\n");
> 				htransp = *transp++;
> 			}

Yeah, as HC pointed out, this is caused by a buggy toolchain. Although
I don't have any disassembly to back it up, I'm willing to bet that it
will show an unconditional load followed by a conditional mov. The
printk() implies a barrier, which will prevent the faulty optimization
from happening.

Haavard
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