Is something wrong with the compiler ?

[Larry Jones]

In article <BURLEY.90Sep27013312 at world.std.com>, burley at world.std.com (James C Burley) writes:
>    >	      a = ( int )(( unsigned ) ( a = ~0 ) >> 1 ));
> 
> Hmm, I thought it was ok -- doesn't "=" serve as a "sequence point" or
> some such thing, and since the lhs of the outer = is so simple it can't
> be "evaluated" before the rhs has been, and the rhs contains the other
> =, one is guaranteed the latter = is performed before the former, right?

No, '=' is not a sequence point.  The question in this case is not when
the lhs gets evaluated, but when the actual storage of the rhs into the
lhs is done.  A compiler would be completely within its rights to store
the final result into a and then overwrite it with ~0.
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