[bazel] Patch rules_foreign_cc to clean build logs

Move rules_foreign_cc from the root MODULE.bazel to its own
`third_party/foreign_cc` directory so that we can patch it to fix an
issue that has not yet been supported upstream yet, in the same way as
we do for e.g. `rules_rust`.

When `rules_foreign_cc` builds using tools such as e.g. Configure+Make,
output files Configure.log and BootstrapGNUMake.log are generated and
emitted which contain references to the absolute path. When building
inside Bazel's sandbox, this produces a non-determinstic output which
changes between each run, as a result, rebuilding OpenOCD will then
change the inputs of any Bazel actions that use OpenOCD, resulting in
a reduced number of cache hits and increasing build times. By making
this determinstic, we improve reproducibility and potentially reduce
build times.

To fix this, this PR introduces a simple patch to completely remove
all the content of this logging output, as it is not needed by any later
steps as part of the build.

Signed-off-by: Alex Jones <[email protected]>

MODULE.bazel

@@ -10,7 +10,6 @@ bazel_dep(name = "bazel_skylib", version = "1.7.1")
 bazel_dep(name = "googletest", version = "1.14.0.bcr.1")
 bazel_dep(name = "platforms", version = "0.0.10")
 bazel_dep(name = "rules_cc", version = "0.0.14")
-bazel_dep(name = "rules_foreign_cc", version = "0.9.0")
 bazel_dep(name = "rules_fuzzing", version = "0.5.2")
 bazel_dep(name = "rules_pkg", version = "1.0.1")
 
@@ -35,6 +34,8 @@ include("//third_party/rust:rust.MODULE.bazel")
 
 include("//third_party/python:python.MODULE.bazel")
 
+include("//third_party/foreign_cc:foreign_cc.MODULE.bazel")
+
 # Repository rules:
 bitstreams_repo = use_repo_rule("//rules:bitstreams.bzl", "bitstreams_repo")
 

third_party/foreign_cc/BUILD

@@ -0,0 +1,5 @@
+# Copyright lowRISC contributors (OpenTitan project).
+# Licensed under the Apache License, Version 2.0, see LICENSE for details.
+# SPDX-License-Identifier: Apache-2.0
+
+package(default_visibility = ["//visibility:public"])

third_party/foreign_cc/foreign_cc.MODULE.bazel

@@ -0,0 +1,18 @@
+# Copyright lowRISC contributors (OpenTitan project).
+# Licensed under the Apache License, Version 2.0, see LICENSE for details.
+# SPDX-License-Identifier: Apache-2.0
+
+# Dependencies:
+bazel_dep(name = "rules_foreign_cc", version = "0.9.0")
+
+# Overrides and patches:
+single_version_override(
+    module_name = "rules_foreign_cc",
+    patches = [
+        # Patch to remove all build log file output when using rules_foreign_cc
+        # toolchains to ensure deterministic Bazel builds. See upstream issue:
+        # https://github.com/bazel-contrib/rules_foreign_cc/issues/1313
+        "//third_party/foreign_cc/patches:rules_foreign_cc.remove_log_output.patch",
+    ],
+    version = "0.9.0",
+)

third_party/foreign_cc/patches/BUILD

@@ -0,0 +1,5 @@
+# Copyright lowRISC contributors (OpenTitan project).
+# Licensed under the Apache License, Version 2.0, see LICENSE for details.
+# SPDX-License-Identifier: Apache-2.0
+
+package(default_visibility = ["//visibility:public"])

third_party/foreign_cc/patches/rules_foreign_cc.remove_log_output.patch

@@ -0,0 +1,13 @@
+diff --git foreign_cc/private/framework.bzl foreign_cc/private/framework.bzl
+index c84c217..f43da2c 100644
+--- foreign_cc/private/framework.bzl
++++ foreign_cc/private/framework.bzl
+@@ -561,7 +561,7 @@ def wrap_outputs(ctx, lib_name, configure_name, script_text, build_script_file =
+     cleanup_on_success_function = create_function(
+         ctx,
+         "cleanup_on_success",
+-        "rm -rf $BUILD_TMPDIR $EXT_BUILD_DEPS",
++        "rm -rf $BUILD_TMPDIR $EXT_BUILD_DEPS && echo > $BUILD_LOG",
+     )
+     cleanup_on_failure_function = create_function(
+         ctx,