Warp wrote:
>   As I said, the 'register' keyword is a no-op. I would bet that most
> if not all modern compilers simply ignore it completely (except when
> checking for correct syntactical usage, just for backwards compatibility;
> after that check they most probably just drop it completely).

Please be advised that your statement is incorrect. 'register' is not
defined to be a "no-op" at all. See for example ISO/IEC 14882:2003 (or 1998
if you like, either way it is the ISO C++ standard) section 7.1.1 number 3.
Specifically, it is a hint to the compiler that "the object so declared will
be heavily used". Of course, it is true that some modern compilers
completely ignore it, but that is more due to their register allocators not
being able to handle external priority hints rather than the keyword being
specified to be a "no-op" anywhere. Also note that is is completely legal to
declare a float or double as 'register', it I completely reasonable to
expect a compiler to be able to use this hint to optimise the usage of
floating-point registers (except that a x87 FPU does not have registers but
a stack, most RISC processors do of course have a full complement of
floating-point registers).

	Thorsten

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