code bloat from constructor and destructor generation

[Stuart Hastings]

On Monday, Dec 9, 2002, at 11:05 US/Pacific, Clint Laschkewitsch wrote:

> I'm working on an embedded system where memory is a major constraint.
>
> In looking at code that is being generated by the gcc compiler and 
> trying
> to determine how we can reduce code size, I was surprised to see 2 
> copies
> of a constructor and 2 copies of a destructor in the C++ classes we 
> have
> defined.
>
> For some of the C++ classes, this is not a big deal because the
> constructors and destructors are very simple and have little code.
> However, we have other classes where both the constructor and 
> destructor
> have quite a bit of code to them.  So getting 2 copies of each is a
> problem.
>
> Can anyone tell me why the compiler is generating two copies?  What 
> problem
> is the compiler trying to solve that the requires separate copies of 
> the
> code?  It appears that using various optimization levels (-O2, -O3, 
> -Os,
> etc.)  does not eliminate any copies.
>
> Also, is there anyway that this can be avoided - compiler options, 
> pragmas,
> #defines, etc that would tell the compiler not to do this?  If it 
> helps,
> many of the C++ classes which are causing space problems will not be
> subclassed so we don't have to worry about some other class inheriting 
> from
> the base class.

http://gcc.gnu.org/ml/gcc-patches/2002-08/msg00354.html

stuart hastings
Apple Computer