Hi defining a tess control shader gl_PerVertex using explicit sizing with gl_MaxPatchVertices fails compilation saying it requires: #extension GL_NV_gpu_shader5 : enable
You probably confused the compiler when you redeclare [var]gl_PerVertex[/var] by adding a bunch of variables to it. That’s not allowed. The spec is very clear; you can only redeclare them with their current set of members.
If you have user-defined values, you need a user-defined interface block to stick them in.