[boost] Re: ETI bug and iterators

From: David Abrahams (dave_at_[hidden])
Date: 2004-08-17 09:37:36

"Yitzhak Sapir" <yitzhak.sapir_at_[hidden]> writes:

> Hello.
>
> I am in the process of upgrading code to use boost 1.31.0 for MSVC6.5.
> During this process I happened upon minimum_category.hpp which
> contains "ETI workarounds".  Now, it seems that the ETI workarounds
> cause the compilation to fail, with the error message: constant
> expression expected.  Particularly, we are creating zip iterators to
> two STLPort vectors.  In debug iterator mode, I get the following
> error.  (minimum_category.hpp was modified a bit

Post the error you get with an unmodified minimum_category.hpp,
please.  It's hard to analyze when the line numbers are wrong.

> but the problem is
> in the instantiation of boost::is_same<T1 or T2,int>).  
                                         ^^^^^^^^

Huh?  That's not valid regardless of any ETI workarounds.

> If I remove
> the ETI "workarounds" the code compiles fine.  So my question is what
> is ETI, what does the ETI workaround provide

"early template instantiation"; See http://tinyurl.com/4kaf7

-- 
Dave Abrahams
Boost Consulting
http://www.boost-consulting.com