[pooma-dev] Re: InlineEvaluator implementation question

[Mark Mitchell]

> Hmm - as both, lhs and rhs are declared const, isnt this enough to tell
> the compiler? Or has the compiler to assume every function call can have
> a side-effect on any (but local) variable?

This is the classic "pointer aliasing" problem for compilers; the
modifications to lhs (via the write operatin in the loop) might,
from the compiler's point of view, change the rhs.  The copies allow
a good compiler to tell that this cannot happen.

> Well, at least gcc creates worse (larger) code with copying than without.

Yes; GCC has a ways to go in this regard.

-- 
Mark Mitchell                mark at codesourcery.com
CodeSourcery, LLC            http://www.codesourcery.com