[U-Boot-Users] possible ELDK4 gcc compiler bug

[Matthias Fuchs]

On Thursday 07 December 2006 17:42, Rune Torgersen wrote:
> > -----Original Message-----
> > From:  Matthias Fuchs
> > *)FPGA_BA;
> > Making 'fpga' static solves the problem. But why?
> > 
> 
> Making it volatile will solve it.
I tried that - of course. But it didn't solve the problem.

> 
> The reason is that the ctrl member is not used anywhere else (except for
> some printf's) sothe compiler just strores the value in a register an
> optimizes away the access to the datastructure (and your hardware). 
> By making it volatile, you force the compiler to never optimize away the
> accesses.
> 
> BTW. your original code would probably have worked with -O0
> optimizattion level.
Yes, it does.

Matthias

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