The various <gc-specific>_globals.hpp files are not supposed to be directly included. They don't do anything on their own. Instead, gc_globals.hpp should be included. It includes the various gc-specific files and applies DECLARE_FLAGS to define the flags from the included headers.
For most GCs that pattern is correctly followed. However, there are several direct includes of g1_globals.hpp.
For most GCs that pattern is correctly followed. However, there are several direct includes of g1_globals.hpp.