C++ / Bazel: How to include angle <> bracket system headers?

Question

Problem: I'm struggling to build against an external dependency included with angle brackets.

Background: I have a header file which includes the Eigen library as so:

#include <Eigen/Dense>

This is installed locally on the system as an external dependency. For various reasons, modifying how dependencies are installed isn't a realistic option currently.

So I need a consistent encapsulate external dependencies as Bazel targets. Currently I'm working on a header only target that looks like this:

cc_library(
   name = "my_library",
   hdrs = [ "some/local/header.h"],
   textual_hdrs = ["@system_deps//:eigen3"],
   deps = ["@system_deps//:eigen3"],
)

This is based on my understanding that (1) non-.h files need to be in textual_hdrs and (2) the fact that it definitely doesn't see it when it's not part of deps. But I admit I'm grasping in the dark here.

This of course points at my WORKSPACE:

new_local_repository(
  name = "system_deps".
  path = "/usr/include/eigen3",
  build_file_content = """
     cc_library(
       name="eigen3",
       textual_hrds = glob["Eigen/*"]),
       visibility = ["//visibility:public"],
     )
  """,
  )

Result: error: 'Eigen/Dense' file not found with blah blah

(This occurs when my header file is include somewhere else.)

Interestingly it does somehow find Eigen/Dense, as it complains (correctly) it can't find another file included. Not sure if

So: what's the right way to do this? I've read other similar questions but haven't quite grasped how to encapsulate these external dependencies.

Answer 1

Does the attribute cc_binary.includes help?