No offense meant, but there’s between a few hundreds and a few thousand persons proving you wrong on each puzzle. Historically, every time someone blamed the tests/validators, it turned out their code had a bug.
Also, it is very plausible for a compiler to be more permissive than another, or to support different features. MSVC is well reputed to be on the permissive side and GCC on the restrictive side. A common occurrence is how MSVC tolerates non-const references on temporary object in a function argument, where GCC refuses to do so.
Like zerlyony said, showing the error message with the code will be much more helpful to you.