Templates are historically hard to get binary-level compatability with.
Remember, to use a template, you use the source code of the template. So,
if one object model (the VC 6.0 one) is compiled against a template (using
the source code from the VC 6.0 headers), and attempts to link against
another object module (the VC 7.0 one) which was compiled against a
different version of the template (using the source code from the VC 7.0
headers), it's not gonna work. The different object modules are going to
have different definitions for the templates, and those definitions are
going to conflict somehow - one possible conflict would be for it to not be
possible to pass template-derived objects between the two libraries because
of the definition of the class itself is actually different, and another way
would be for the template code in the object module to not be able to link
because it requires some supporting static function that has changed (which
is what you are describing, with linker errors).
In order to maintain backward compat. with the template libraries, Microsof
would have to simply not change them - keep them completely static. Sadly,
that means that other people would be complaining about bugs not being
fixed, the libraries not coming up to be in line with the spec, etc.
You could try linking against the old VC 6.0 version of the STL static
library, to see if it resolves the linker errors. But if you are actually
passing STL-derived classes between your VC 7.0-compiled code and the old VC
6.0-compiled code, you are going to be in trouble (unless somehow not a
single line of code has changed for that particular template, between the
two versions).
--Don
