Make toolchains use directory markers instead of strings.

BEGIN_PUBLIC
Make toolchains use directory markers instead of strings.

You now refer to this instead of a string containing the repo mapped path.
END_PUBLIC

PiperOrigin-RevId: 639946886
Change-Id: I409be7b7002252b06562a2982a2568e79811877d

MODULE.bazel

@@ -4,7 +4,7 @@ module(
     compatibility_level = 1,
 )
 
-bazel_dep(name = "bazel_skylib", version = "1.3.0")
+bazel_dep(name = "bazel_skylib", version = "1.7.1")
 bazel_dep(name = "platforms", version = "0.0.7")
 
 cc_configure = use_extension("@bazel_tools//tools/cpp:cc_configure.bzl", "cc_configure_extension")

cc/toolchains/impl/toolchain_config.bzl

@@ -14,6 +14,7 @@
 """Implementation of the cc_toolchain rule."""
 
 load("@bazel_skylib//rules:common_settings.bzl", "BuildSettingInfo")
+load("@bazel_skylib//rules/directory:providers.bzl", "DirectoryInfo")
 load(
     "//cc/toolchains:cc_toolchain_info.bzl",
     "ActionTypeConfigSetInfo",
@@ -64,13 +65,22 @@ def _cc_toolchain_config_impl(ctx):
 
     legacy = convert_toolchain(toolchain_config)
 
+    sysroot = None
+    if ctx.attr.sysroot:
+        sysroot = ctx.attr.sysroot[DirectoryInfo].path
+
+    cxx_builtin_include_directories = [
+        d[DirectoryInfo].path
+        for d in ctx.attr.cxx_builtin_include_directories
+    ]
+
     return [
         toolchain_config,
         cc_common.create_cc_toolchain_config_info(
             ctx = ctx,
             action_configs = legacy.action_configs,
             features = legacy.features,
-            cxx_builtin_include_directories = ctx.attr.cxx_builtin_include_directories,
+            cxx_builtin_include_directories = cxx_builtin_include_directories,
             # toolchain_identifier is deprecated, but setting it to None results
             # in an error that it expected a string, and for safety's sake, I'd
             # prefer to provide something unique.
@@ -81,7 +91,7 @@ def _cc_toolchain_config_impl(ctx):
             compiler = ctx.attr.compiler,
             abi_version = ctx.attr.abi_version,
             abi_libc_version = ctx.attr.abi_libc_version,
-            builtin_sysroot = ctx.attr.sysroot or None,
+            builtin_sysroot = sysroot,
         ),
         # This allows us to support all_files.
         # If all_files was simply an alias to
@@ -103,21 +113,18 @@ cc_toolchain_config = rule(
         "_builtin_features": attr.label(default = "//cc/toolchains/features:all_builtin_features"),
         "_enabled": attr.label(default = "//cc/toolchains:experimental_enable_rule_based_toolchains"),
 
-        # Attributes from create_cc_toolchain_config_info.
-        # artifact_name_patterns is currently unused. Consider adding it later.
-        # TODO: Consider making this into a label_list that takes a
-        #  cc_directory_marker rule as input.
-        "cxx_builtin_include_directories": attr.string_list(),
+        # Attributes translated from legacy cc toolchains.
+        "sysroot": attr.label(providers = [DirectoryInfo]),
+        "cxx_builtin_include_directories": attr.label_list(providers = [DirectoryInfo]),
+
+        # TODO: remove these fields. I'm pretty sure they're unnecessary with
+        # --incompatible_enable_cc_toolchain_resolution.
         "target_system_name": attr.string(),
         "target_cpu": attr.string(),
         "target_libc": attr.string(),
         "compiler": attr.string(mandatory = True),
         "abi_version": attr.string(),
         "abi_libc_version": attr.string(),
-        # tool_paths currently unused.
-        # TODO: Consider making this into a label that takes a
-        #  cc_directory_marker rule as an input.
-        "sysroot": attr.string(),
     },
     provides = [ToolchainConfigInfo],
 )

tests/rule_based_toolchain/testdata/BUILD

@@ -1,7 +1,16 @@
 load("@bazel_skylib//rules:native_binary.bzl", "native_binary")
+load("@bazel_skylib//rules/directory:directory.bzl", "directory")
 
 package(default_visibility = ["//tests/rule_based_toolchain:__subpackages__"])
 
+directory(
+    name = "directory",
+    srcs = glob(
+        ["*"],
+        exclude = ["BUILD"],
+    ),
+)
+
 exports_files(
     glob(
         ["*"],

tests/rule_based_toolchain/toolchain_config/BUILD

@@ -47,7 +47,11 @@ util.helper_target(
     action_type_configs = [":compile_config"],
     args = [":c_compile_args"],
     compiler = "gcc-4.1.1",
+    cxx_builtin_include_directories = [
+        "//tests/rule_based_toolchain/testdata:directory",
+    ],
     skip_experimental_flag_validation_for_test = True,
+    sysroot = "//tests/rule_based_toolchain/testdata:directory",
     target_cpu = "k8",
     target_libc = "glibc-2.2.2",
     target_system_name = "local",