[llvm] [Bazel] Make LLVM config headers configurable (PR #126729)

[Aaron Siddhartha Mondal via llvm-commits]

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@@ -0,0 +1,158 @@
+# This file is licensed under the Apache License v2.0 with LLVM Exceptions.
+# See https://llvm.org/LICENSE.txt for license information.
+# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+"""Configurable build attributes for LLVM."""
+
+load("@bazel_skylib//lib:selects.bzl", "selects")
+load("@bazel_skylib//rules:common_settings.bzl", "bool_flag", "string_flag")
+
+# To view the configurable build attributes in this file:
+#
+#   bazel query 'kind(".*_flag", @llvm-project//llvm/config:all)'
+
+selects.config_setting_group(
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aaronmondal wrote:

Note: The `config_setting_group`s here (and similarly for the platforms) mirror what we had previously. In the long run these should probably map out all possible triples.

https://github.com/llvm/llvm-project/pull/126729