Do not pass native libraries to rlib compilations

proto/proto.bzl

@@ -217,6 +217,7 @@ def _rust_proto_compile(protos, descriptor_sets, imports, crate_name, ctx, is_gr
     return rustc_compile_action(
         ctx = ctx,
         toolchain = find_toolchain(ctx),
+        crate_type = "rlib",
         crate_info = rust_common.crate_info(
             name = crate_name,
             type = "rlib",

rust/private/clippy.bzl

@@ -49,6 +49,7 @@ def _clippy_aspect_impl(target, ctx):
 
     toolchain = find_toolchain(ctx)
     crate_info = target[rust_common.crate_info]
+    crate_type = crate_info.type
 
     if crate_info.is_test:
         root = crate_info.root
@@ -89,6 +90,7 @@ def _clippy_aspect_impl(target, ctx):
         toolchain.clippy_driver.path,
         cc_toolchain,
         feature_configuration,
+        crate_type,
         crate_info,
         dep_info,
         output_hash = determine_output_hash(root),

rust/private/rust.bzl

@@ -155,9 +155,10 @@ def _rust_library_impl(ctx):
     output_hash = determine_output_hash(crate_root)
 
     crate_name = name_to_crate_name(ctx.label.name)
+    crate_type = getattr(ctx.attr, "crate_type")
     rust_lib_name = _determine_lib_name(
         crate_name,
-        ctx.attr.crate_type,
+        crate_type,
         toolchain,
         output_hash,
     )
@@ -166,9 +167,10 @@ def _rust_library_impl(ctx):
     return rustc_compile_action(
         ctx = ctx,
         toolchain = toolchain,
+        crate_type = crate_type,
         crate_info = rust_common.crate_info(
             name = crate_name,
-            type = ctx.attr.crate_type,
+            type = crate_type,
             root = crate_root,
             srcs = ctx.files.srcs,
             deps = ctx.attr.deps,
@@ -201,6 +203,7 @@ def _rust_binary_impl(ctx):
     return rustc_compile_action(
         ctx = ctx,
         toolchain = toolchain,
+        crate_type = crate_type,
         crate_info = rust_common.crate_info(
             name = crate_name,
             type = crate_type,
@@ -230,14 +233,14 @@ def _rust_test_common(ctx, toolchain, output):
     _assert_no_deprecated_attributes(ctx)
 
     crate_name = name_to_crate_name(ctx.label.name)
-
+    crate_type = "bin"
     if ctx.attr.crate:
         # Target is building the crate in `test` config
         # Build the test binary using the dependency's srcs.
         crate = ctx.attr.crate[rust_common.crate_info]
         target = rust_common.crate_info(
             name = crate_name,
-            type = crate.type,
+            type = crate_type,
             root = crate.root,
             srcs = crate.srcs + ctx.files.srcs,
             deps = crate.deps + ctx.attr.deps,
@@ -252,7 +255,7 @@ def _rust_test_common(ctx, toolchain, output):
         # Target is a standalone crate. Build the test binary as its own crate.
         target = rust_common.crate_info(
             name = crate_name,
-            type = "lib",
+            type = crate_type,
             root = crate_root_src(ctx.attr, ctx.files.srcs, "lib"),
             srcs = ctx.files.srcs,
             deps = ctx.attr.deps,
@@ -267,6 +270,7 @@ def _rust_test_common(ctx, toolchain, output):
     return rustc_compile_action(
         ctx = ctx,
         toolchain = toolchain,
+        crate_type = crate_type,
         crate_info = target,
         rust_flags = ["--test"],
         environ = ctx.attr.env,

rust/private/rustc.bzl

@@ -364,6 +364,7 @@ def construct_arguments(
         tool_path,
         cc_toolchain,
         feature_configuration,
+        crate_type,
         crate_info,
         dep_info,
         output_hash,
@@ -383,6 +384,7 @@ def construct_arguments(
         tool_path (str): Path to rustc
         cc_toolchain (CcToolchain): The CcToolchain for the current target.
         feature_configuration (FeatureConfiguration): Class used to construct command lines from CROSSTOOL features.
+        crate_type (str): Crate type of the current target.
         crate_info (CrateInfo): The CrateInfo provider of the target crate
         dep_info (DepInfo): The DepInfo provider of the target crate
         output_hash (str): The hashed path of the crate root
@@ -508,7 +510,7 @@ def construct_arguments(
             args.add("--codegen=linker=" + ld)
             args.add_joined("--codegen", link_args, join_with = " ", format_joined = "link-args=%s")
 
-        add_native_link_flags(args, dep_info)
+        add_native_link_flags(args, dep_info, crate_type)
 
     # These always need to be added, even if not linking this crate.
     add_crate_link_flags(args, dep_info)
@@ -541,6 +543,7 @@ def construct_arguments(
 def rustc_compile_action(
         ctx,
         toolchain,
+        crate_type,
         crate_info,
         output_hash = None,
         rust_flags = [],
@@ -550,6 +553,7 @@ def rustc_compile_action(
     Args:
         ctx (ctx): The rule's context object
         toolchain (rust_toolchain): The current `rust_toolchain`
+        crate_type (str): Crate type of the current target
         crate_info (CrateInfo): The CrateInfo provider for the current target.
         output_hash (str, optional): The hashed path of the crate root. Defaults to None.
         rust_flags (list, optional): Additional flags to pass to rustc. Defaults to [].
@@ -588,6 +592,7 @@ def rustc_compile_action(
         toolchain.rustc.path,
         cc_toolchain,
         feature_configuration,
+        crate_type,
         crate_info,
         dep_info,
         output_hash,
@@ -816,13 +821,18 @@ def _get_crate_dirname(crate):
     """
     return crate.output.dirname
 
-def add_native_link_flags(args, dep_info):
+def add_native_link_flags(args, dep_info, crate_type):
     """Adds linker flags for all dependencies of the current target.
 
     Args:
         args (Args): The Args struct for a ctx.action
-        dep_info (DepInfo): Dependeincy Info provider
+        dep_info (DepInfo): Dependency Info provider
+        crate_type: Crate type of the current target
+
     """
+    if crate_type in ["lib", "rlib"]:
+        return
+
     native_libs = depset(transitive = [dep_info.transitive_dylibs, dep_info.transitive_staticlibs])
     args.add_all(native_libs, map_each = _get_dirname, uniquify = True, format_each = "-Lnative=%s")
     args.add_all(dep_info.transitive_dylibs, map_each = get_lib_name, format_each = "-ldylib=%s")

rust/rust.bzl

@@ -12,7 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-# buildifier: disable=module-docstring
+"""Public entry point to all Rust rules and supported APIs."""
+
 load(
     "//rust/private:clippy.bzl",
     _rust_clippy = "rust_clippy",

rust/rust_common.bzl

@@ -0,0 +1,32 @@
+# Copyright 2015 The Bazel Authors. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Module with Rust definitions required to write custom Rust rules."""
+
+CrateInfo = provider(
+    doc = "A provider containing general Crate information.",
+    fields = {
+        "aliases": "Dict[Label, String]: Renamed and aliased crates",
+        "deps": "List[Provider]: This crate's (rust or cc) dependencies' providers.",
+        "edition": "str: The edition of this crate.",
+        "is_test": "bool: If the crate is being compiled in a test context",
+        "name": "str: The name of this crate.",
+        "output": "File: The output File that will be produced, depends on crate type.",
+        "proc_macro_deps": "List[CrateInfo]: This crate's rust proc_macro dependencies' providers.",
+        "root": "File: The source File entrypoint to this crate, eg. lib.rs",
+        "rustc_env": "Dict[String, String]: Additional `\"key\": \"value\"` environment variables to set for rustc.",
+        "srcs": "List[File]: All source Files that are part of the crate.",
+        "type": "str: The type of this crate. eg. lib or bin",
+    },
+)

test/unit/BUILD

@@ -0,0 +1 @@
+# BUILD file intentionally left empty

test/unit/native_deps/BUILD

@@ -0,0 +1,4 @@
+load(":native_deps_test.bzl", "native_deps_test_suite")
+
+############################ UNIT TESTS #############################
+native_deps_test_suite(name = "native_deps_test_suite")

test/unit/native_deps/bin_using_native_dep.rs

@@ -0,0 +1,6 @@
+extern "C" {
+    fn native_dep() -> isize;
+}
+fn main() {
+    println!("{}", unsafe { native_dep() })
+}

test/unit/native_deps/lib_using_native_dep.rs

@@ -0,0 +1,6 @@
+extern "C" {
+    fn native_dep() -> isize;
+}
+pub fn use_native_dep() {
+    println!("{}", unsafe { native_dep() })
+}

test/unit/native_deps/native_dep.cc

@@ -0,0 +1 @@
+extern "C" int native_dep() { return 42; }