A popular format for describing how to compile object files for a project is the JSON Compilation Database (a.k.a. compile_commands.json) [1]. This file can be used directly by IDEs such as Visual Studio Code and CLion as well as "language servers" such as cquery [2] and rtags [3].

It's currently possible to use tools such as Bear [4] to generate this file for the JDK, but this requires a full build to complete before the information is available.

However, it is possible to generate this information without actually compiling the files in question. This makes it possible to quickly obtain this information on freshly cloned source which can then be used by the tool of choice to start working immediately, without waiting for a full build.

[1] https://clang.llvm.org/docs/JSONCompilationDatabase.html
[2] https://github.com/cquery-project/cquery
[3] https://github.com/Andersbakken/rtags
[4] https://github.com/rizsotto/Bear