Re: exceptions (was Re: First stage of Quesa changes now complete)

[James W. W. <os...@jw...>]

On Jan 27, 2005, at 8:06 AM, Joseph J. Strout wrote:

> I hope I'm not (again) chiming in late here, but I hope we're building 
> Quesa (or at least, making it possible to build quesa) with exception 
> support turned off.  In at least some compilers, having exceptions on 
> incurs a noticeable overhead even if you're not using them.

As I may have mentioned before, the STL was designed with the 
expectation that exception support would be on.  I think it would be a 
poor idea to build it with exceptions off.  That said, the Quesa source 
code does not currently contain any explicit throw statements.  Hmm, I 
see that I did use one new statement without nothrow, I guess I should 
fix that.  What happens to a try/catch block if exceptions are off?

What compilers have a noticeable overhead for exceptions?  I don't 
think either gcc or CodeWarrior fall into that category.

> My experience also matches Dair's, i.e., that in C++ code, exceptions 
> tend to cause more grief than good.

I strongly disagree with that, if exceptions are used well.  It took a 
few years for people to learn how to use them well, e.g., how to write 
exception-safe code, so some early experience may have been negative.  
I've read a bunch of books to learn good C++ techniques, and I can't 
remember any book suggesting that one not use exceptions.
--
<http://www.jwwalker.com/>