Different behavior of compilers with array allocation

Question

I recently found a interesting behaviour of g++ when compared with MSVC++ 2008. Consider this tiny program:

#include 

const int ARR_LENGTH =          


        

Answer 1

C99 (the most recent version of the C standard) does allow dynamically sized arrays. However, the feature is not supported by Visual Studio (which only implements C89 support)

In C++ it is not, and probably will never be, valid.