Re: [Boost-users] [serialization] binary_iarchiveperformancedegradation with Intel 9.0 compiler

I was out whacking weeds today and was thinking about this. I'm going to guess that the unseen code in Bill example has a number of BOOST_CLASS_EXPORT macros. The current version will instanciate code for every combination of exported type and included archive class. At startup there will be three times as much code invoked to "register" these combinations. During in the course of serialization, there are look ups into the tables built at init time. These are stl sets, map and the like. Its possible that the fact this combination of compiler/library implementation consumes a disproportionate time under these circumstances. I would guess that one would need to use a profiler to get more information on this. Currently code is instantiate for each combination of exported type and included archive. Question for Dave: Is this the same in the new improved version of export (1.35) or does the new one only instantiate code for each archive actually used with an << or & operator? - Just asking. Robert Ramey David Abrahams wrote:

"Robert Ramey" writes:

...

How does the size of the executable vary. It shouldn't - but if it does that would indicate extra code being instantiated.

Of course it should vary if any classes are exported. The whole point of BOOST_CLASS_EXPORT is to instantiate a piece of code for each element in the cross-product of exported classes and visible archives. If you make more archives visible in the translation unit, more code will necessarily be instantiated (and run at startup).