| Re: [eigen] StdVector again |
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Hi
On Thursday 27 August 2009 13:45:40 Markus Moll wrote:
> the problems reported in the two recent mails on StdVector sounded
> suspiciously familiar to me.
> Indeed, both are due to a problem solved quite a while ago, but
> unfortunately the changes are in the default branch, while the current
> branch seems to be 2.0, which does not contain them.
Ah, sorry. If my understanding is correct, the 2.0 branch is the stable
branch, while default is development (right?)
Daniel, you essentially ran into two problems. StdVector in 2.0 redefines
std::vector so that it can be used with aligned Eigen types. What happened is:
1. The redefinition of std::vector makes programs compiled with Eigen
incompatible with libraries that export anything containing std::vector (the
std::vector type for compiling the library is different from the one used for
compiling your program). It _might_ work if you carefully include the library
headers (boost in your case) _before_ including StdVector. Of course, then you
cannot use any Eigen vectors before that point, either. However, this might be
arbitrarily complex if not impossible in larger projects.
2. The vector interface in the stable branch is not complete and does not
satisfy the requirements imposed by the standard. This is why your constructor
call did not succeed.
To the developers: Would it be possible to include the fixes in the 2.0 branch
as well? Granted, it would change the interface but I really think that most
people who currently use StdVector run into the above mentioned problems
anyway. A large warning box telling people that it's now necessary to use
aligned_allocator would probably be sufficient, wouldn't it?
Markus
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