As explained earlier, LLVM started as a project that was dependent on GCC when it still lacked its own C/C++ frontend. In those instances, to use LLVM, you needed to download a hacked GCC source tree called llvm-gcc and compile it in its entirety. Since the compilation involved the full GCC package, it was a very time-consuming and tricky task, requiring knowledge of all the necessary GNU lore to rebuild GCC by yourself. The DragonEgg project appeared as a clever solution to leverage the GCC plugin system, separating the LLVM logic in its own and much smaller code tree. In this way, the users no longer needed to rebuild the entire GCC package, but just a plugin, and then load it into GCC. DragonEgg is also the sole project under the LLVM project umbrella that is licensed under GPL.

Even with the rise of Clang, DragonEgg persists today because Clang only handles the C and C++ languages, while GCC is able to parse a wider variety of languages. By using the DragonEgg...