From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Austin Schuh <austin.linux@gmail.com>
Date: Sat, 9 Aug 2025 12:45:23 -0700
Subject: [PATCH 3/3] Add build files from bzlmod for eigen

This makes it so our vendored version of eigen matches the same API as
the upstream eigen in bcr.
---
 BUILD.bazel | 64 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 WORKSPACE   |  0
 2 files changed, 64 insertions(+)
 create mode 100644 BUILD.bazel
 create mode 100644 WORKSPACE

diff --git a/BUILD.bazel b/BUILD.bazel
new file mode 100644
index 0000000000000000000000000000000000000000..38ce6cb417485fb37cafaf1e0f536e7ac56706b0
--- /dev/null
+++ b/BUILD.bazel
@@ -0,0 +1,64 @@
+load("@rules_cc//cc:cc_library.bzl", "cc_library")
+load("@rules_license//rules:license.bzl", "license")
+
+package(
+    default_applicable_licenses = [
+        ":license.APACHE",
+        ":license.BSD",
+        ":license.MINPACK",  # Only used by unsupported/** not by Eigen/**.
+        ":license.MPL2",
+    ],
+)
+
+exports_files(glob(["COPYING.*"]))
+
+# Note: Eigen is primarily an MPL2 library with small bits of code under other
+# licenses. Previous versions of Eigen contained LGPL code which needed to be
+# carefully excluded, but as of approximately 2023-02-07 all LGPL code has been
+# removed upstream so does not need any special handling here.
+
+license(
+    name = "license.APACHE",
+    license_kinds = ["@rules_license//licenses/spdx:Apache-2.0"],
+    license_text = "COPYING.APACHE",
+)
+
+license(
+    name = "license.BSD",
+    license_kinds = ["@rules_license//licenses/spdx:BSD-3-Clause"],
+    license_text = "COPYING.BSD",
+)
+
+license(
+    name = "license.MINPACK",
+    license_kinds = ["@rules_license//licenses/spdx:BSD-3-Clause-Attribution"],
+    license_text = "COPYING.MINPACK",
+)
+
+license(
+    name = "license.MPL2",
+    license_kinds = ["@rules_license//licenses/spdx:MPL-2.0"],
+    license_text = "COPYING.MPL2",
+)
+
+HDRS = glob(
+    [
+        "Eigen/**",
+        "unsupported/Eigen/**",
+    ],
+    exclude = [
+        # We don't want any documentation files.
+        "**/*.md",
+        "**/*.txt",
+        "unsupported/Eigen/NonLinearOptimization",
+        #"unsupported/Eigen/MatrixFunctions",
+        "unsupported/Eigen/Polynomials",
+    ],
+)
+
+cc_library(
+    name = "eigen",
+    hdrs = HDRS,
+    includes = ["."],
+    visibility = ["//visibility:public"],
+)
diff --git a/WORKSPACE b/WORKSPACE
new file mode 100644
index 0000000000000000000000000000000000000000..e69de29bb2d1d6434b8b29ae775ad8c2e48c5391