I've got a class in a DLL that applications use. If I add members,
even private ones, to my class the application has to recompile
because the size of the class (e.g. the chunk of memory allocated
when I new a class) increases. This is somewhat of a problem
because I have many applications running in many places.

Currently I'm contemplating adding a feature to the class that
could easily be represented by a private static data member (int)
Will adding a static member change the layout? In other words,
do I risk heap corruption if I add a static member and not recompile?
I'm guessing that statics class members are treated like global
variables by the linker but I'm not sure.

Thanks,
Andrew Queisser

No. (You are correct).  Static class members belong to the class only in terms
of scope; they do not increase the size of the class objects, because they are
not associated with any single object.  Their storage is like global variables,
as you guessed.