rules_rust: enable pipelined compilation.

.bazelci/presubmit.yml

@@ -15,6 +15,7 @@ default_windows_targets: &default_windows_targets
   - "-//bindgen/..."
   - "-//test/proto/..."
   - "-//tools/rust_analyzer/..."
+  - "-//test/unit/pipelined_compilation/..."
 crate_universe_vendor_example_targets: &crate_universe_vendor_example_targets
   - "//vendor_external:crates_vendor"
   - "//vendor_local_manifests:crates_vendor"

docs/flatten.md

@@ -1350,8 +1350,8 @@ A test rule for performing `rustfmt --check` on a set of targets
 ## CrateInfo
 
 <pre>
-CrateInfo(<a href="#CrateInfo-aliases">aliases</a>, <a href="#CrateInfo-compile_data">compile_data</a>, <a href="#CrateInfo-deps">deps</a>, <a href="#CrateInfo-edition">edition</a>, <a href="#CrateInfo-is_test">is_test</a>, <a href="#CrateInfo-name">name</a>, <a href="#CrateInfo-output">output</a>, <a href="#CrateInfo-owner">owner</a>, <a href="#CrateInfo-proc_macro_deps">proc_macro_deps</a>, <a href="#CrateInfo-root">root</a>,
-          <a href="#CrateInfo-rustc_env">rustc_env</a>, <a href="#CrateInfo-srcs">srcs</a>, <a href="#CrateInfo-type">type</a>, <a href="#CrateInfo-wrapped_crate_type">wrapped_crate_type</a>)
+CrateInfo(<a href="#CrateInfo-aliases">aliases</a>, <a href="#CrateInfo-compile_data">compile_data</a>, <a href="#CrateInfo-deps">deps</a>, <a href="#CrateInfo-edition">edition</a>, <a href="#CrateInfo-is_test">is_test</a>, <a href="#CrateInfo-metadata">metadata</a>, <a href="#CrateInfo-name">name</a>, <a href="#CrateInfo-output">output</a>, <a href="#CrateInfo-owner">owner</a>,
+          <a href="#CrateInfo-proc_macro_deps">proc_macro_deps</a>, <a href="#CrateInfo-root">root</a>, <a href="#CrateInfo-rustc_env">rustc_env</a>, <a href="#CrateInfo-srcs">srcs</a>, <a href="#CrateInfo-type">type</a>, <a href="#CrateInfo-wrapped_crate_type">wrapped_crate_type</a>)
 </pre>
 
 A provider containing general Crate information.
@@ -1366,6 +1366,7 @@ A provider containing general Crate information.
 | <a id="CrateInfo-deps"></a>deps |  depset[DepVariantInfo]: This crate's (rust or cc) dependencies' providers.    |
 | <a id="CrateInfo-edition"></a>edition |  str: The edition of this crate.    |
 | <a id="CrateInfo-is_test"></a>is_test |  bool: If the crate is being compiled in a test context    |
+| <a id="CrateInfo-metadata"></a>metadata |  File: The rmeta file produced for this crate. It is optional.    |
 | <a id="CrateInfo-name"></a>name |  str: The name of this crate.    |
 | <a id="CrateInfo-output"></a>output |  File: The output File that will be produced, depends on crate type.    |
 | <a id="CrateInfo-owner"></a>owner |  Label: The label of the target that produced this CrateInfo    |
@@ -1383,7 +1384,8 @@ A provider containing general Crate information.
 
 <pre>
 DepInfo(<a href="#DepInfo-dep_env">dep_env</a>, <a href="#DepInfo-direct_crates">direct_crates</a>, <a href="#DepInfo-link_search_path_files">link_search_path_files</a>, <a href="#DepInfo-transitive_build_infos">transitive_build_infos</a>,
-        <a href="#DepInfo-transitive_crate_outputs">transitive_crate_outputs</a>, <a href="#DepInfo-transitive_crates">transitive_crates</a>, <a href="#DepInfo-transitive_noncrates">transitive_noncrates</a>)
+        <a href="#DepInfo-transitive_crate_outputs">transitive_crate_outputs</a>, <a href="#DepInfo-transitive_crates">transitive_crates</a>, <a href="#DepInfo-transitive_metadata_outputs">transitive_metadata_outputs</a>,
+        <a href="#DepInfo-transitive_noncrates">transitive_noncrates</a>)
 </pre>
 
 A provider containing information about a Crate's dependencies.
@@ -1399,6 +1401,7 @@ A provider containing information about a Crate's dependencies.
 | <a id="DepInfo-transitive_build_infos"></a>transitive_build_infos |  depset[BuildInfo]    |
 | <a id="DepInfo-transitive_crate_outputs"></a>transitive_crate_outputs |  depset[File]: All transitive crate outputs.    |
 | <a id="DepInfo-transitive_crates"></a>transitive_crates |  depset[CrateInfo]    |
+| <a id="DepInfo-transitive_metadata_outputs"></a>transitive_metadata_outputs |  depset[File]: All transitive metadata dependencies (.rmeta, for crates that provide them) and all transitive object dependencies (.rlib) for crates that don't provide metadata.    |
 | <a id="DepInfo-transitive_noncrates"></a>transitive_noncrates |  depset[LinkerInput]: All transitive dependencies that aren't crates.    |
 
 

docs/providers.md

@@ -10,8 +10,8 @@
 ## CrateInfo
 
 <pre>
-CrateInfo(<a href="#CrateInfo-aliases">aliases</a>, <a href="#CrateInfo-compile_data">compile_data</a>, <a href="#CrateInfo-deps">deps</a>, <a href="#CrateInfo-edition">edition</a>, <a href="#CrateInfo-is_test">is_test</a>, <a href="#CrateInfo-name">name</a>, <a href="#CrateInfo-output">output</a>, <a href="#CrateInfo-owner">owner</a>, <a href="#CrateInfo-proc_macro_deps">proc_macro_deps</a>, <a href="#CrateInfo-root">root</a>,
-          <a href="#CrateInfo-rustc_env">rustc_env</a>, <a href="#CrateInfo-srcs">srcs</a>, <a href="#CrateInfo-type">type</a>, <a href="#CrateInfo-wrapped_crate_type">wrapped_crate_type</a>)
+CrateInfo(<a href="#CrateInfo-aliases">aliases</a>, <a href="#CrateInfo-compile_data">compile_data</a>, <a href="#CrateInfo-deps">deps</a>, <a href="#CrateInfo-edition">edition</a>, <a href="#CrateInfo-is_test">is_test</a>, <a href="#CrateInfo-metadata">metadata</a>, <a href="#CrateInfo-name">name</a>, <a href="#CrateInfo-output">output</a>, <a href="#CrateInfo-owner">owner</a>,
+          <a href="#CrateInfo-proc_macro_deps">proc_macro_deps</a>, <a href="#CrateInfo-root">root</a>, <a href="#CrateInfo-rustc_env">rustc_env</a>, <a href="#CrateInfo-srcs">srcs</a>, <a href="#CrateInfo-type">type</a>, <a href="#CrateInfo-wrapped_crate_type">wrapped_crate_type</a>)
 </pre>
 
 A provider containing general Crate information.
@@ -26,6 +26,7 @@ A provider containing general Crate information.
 | <a id="CrateInfo-deps"></a>deps |  depset[DepVariantInfo]: This crate's (rust or cc) dependencies' providers.    |
 | <a id="CrateInfo-edition"></a>edition |  str: The edition of this crate.    |
 | <a id="CrateInfo-is_test"></a>is_test |  bool: If the crate is being compiled in a test context    |
+| <a id="CrateInfo-metadata"></a>metadata |  File: The rmeta file produced for this crate. It is optional.    |
 | <a id="CrateInfo-name"></a>name |  str: The name of this crate.    |
 | <a id="CrateInfo-output"></a>output |  File: The output File that will be produced, depends on crate type.    |
 | <a id="CrateInfo-owner"></a>owner |  Label: The label of the target that produced this CrateInfo    |
@@ -43,7 +44,8 @@ A provider containing general Crate information.
 
 <pre>
 DepInfo(<a href="#DepInfo-dep_env">dep_env</a>, <a href="#DepInfo-direct_crates">direct_crates</a>, <a href="#DepInfo-link_search_path_files">link_search_path_files</a>, <a href="#DepInfo-transitive_build_infos">transitive_build_infos</a>,
-        <a href="#DepInfo-transitive_crate_outputs">transitive_crate_outputs</a>, <a href="#DepInfo-transitive_crates">transitive_crates</a>, <a href="#DepInfo-transitive_noncrates">transitive_noncrates</a>)
+        <a href="#DepInfo-transitive_crate_outputs">transitive_crate_outputs</a>, <a href="#DepInfo-transitive_crates">transitive_crates</a>, <a href="#DepInfo-transitive_metadata_outputs">transitive_metadata_outputs</a>,
+        <a href="#DepInfo-transitive_noncrates">transitive_noncrates</a>)
 </pre>
 
 A provider containing information about a Crate's dependencies.
@@ -59,6 +61,7 @@ A provider containing information about a Crate's dependencies.
 | <a id="DepInfo-transitive_build_infos"></a>transitive_build_infos |  depset[BuildInfo]    |
 | <a id="DepInfo-transitive_crate_outputs"></a>transitive_crate_outputs |  depset[File]: All transitive crate outputs.    |
 | <a id="DepInfo-transitive_crates"></a>transitive_crates |  depset[CrateInfo]    |
+| <a id="DepInfo-transitive_metadata_outputs"></a>transitive_metadata_outputs |  depset[File]: All transitive metadata dependencies (.rmeta, for crates that provide them) and all transitive object dependencies (.rlib) for crates that don't provide metadata.    |
 | <a id="DepInfo-transitive_noncrates"></a>transitive_noncrates |  depset[LinkerInput]: All transitive dependencies that aren't crates.    |
 
 

proto/proto.bzl

@@ -44,7 +44,7 @@ load("//rust:defs.bzl", "rust_common")
 load("//rust/private:rustc.bzl", "rustc_compile_action")
 
 # buildifier: disable=bzl-visibility
-load("//rust/private:utils.bzl", "compute_crate_name", "determine_output_hash", "find_toolchain", "transform_deps")
+load("//rust/private:utils.bzl", "can_build_metadata", "compute_crate_name", "determine_output_hash", "find_toolchain", "transform_deps")
 
 RustProtoInfo = provider(
     doc = "Rust protobuf provider info",
@@ -212,6 +212,13 @@ def _rust_proto_compile(protos, descriptor_sets, imports, crate_name, ctx, is_gr
         crate_name,
         output_hash,
     ))
+    rust_metadata = None
+    if can_build_metadata(toolchain, ctx, "rlib"):
+        rust_metadata = ctx.actions.declare_file("%s/lib%s-%s.rmeta" % (
+            output_dir,
+            crate_name,
+            output_hash,
+        ))
 
     # Gather all dependencies for compilation
     compile_action_deps = depset(
@@ -234,6 +241,7 @@ def _rust_proto_compile(protos, descriptor_sets, imports, crate_name, ctx, is_gr
             proc_macro_deps = depset([]),
             aliases = {},
             output = rust_lib,
+            metadata = rust_metadata,
             edition = proto_toolchain.edition,
             rustc_env = {},
             is_test = False,

rust/private/common.bzl

@@ -47,6 +47,8 @@ def _create_crate_info(**kwargs):
     """
     if not "wrapped_crate_type" in kwargs:
         kwargs.update({"wrapped_crate_type": None})
+    if not "metadata" in kwargs:
+        kwargs.update({"metadata": None})
     return CrateInfo(**kwargs)
 
 rust_common = struct(

rust/private/providers.bzl

@@ -22,6 +22,7 @@ CrateInfo = provider(
         "deps": "depset[DepVariantInfo]: 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",
+        "metadata": "File: The rmeta file produced for this crate. It is optional.",
         "name": "str: The name of this crate.",
         "output": "File: The output File that will be produced, depends on crate type.",
         "owner": "Label: The label of the target that produced this CrateInfo",
@@ -49,6 +50,7 @@ DepInfo = provider(
         "transitive_build_infos": "depset[BuildInfo]",
         "transitive_crate_outputs": "depset[File]: All transitive crate outputs.",
         "transitive_crates": "depset[CrateInfo]",
+        "transitive_metadata_outputs": "depset[File]: All transitive metadata dependencies (.rmeta, for crates that provide them) and all transitive object dependencies (.rlib) for crates that don't provide metadata.",
         "transitive_noncrates": "depset[LinkerInput]: All transitive dependencies that aren't crates.",
     },
 )

rust/private/rust.bzl

@@ -13,10 +13,12 @@
 # limitations under the License.
 
 # buildifier: disable=module-docstring
+load("@bazel_skylib//lib:paths.bzl", "paths")
 load("//rust/private:common.bzl", "rust_common")
 load("//rust/private:rustc.bzl", "rustc_compile_action")
 load(
     "//rust/private:utils.bzl",
+    "can_build_metadata",
     "compute_crate_name",
     "dedent",
     "determine_output_hash",
@@ -25,7 +27,6 @@ load(
     "get_import_macro_deps",
     "transform_deps",
 )
-
 # TODO(marco): Separate each rule into its own file.
 
 def _assert_no_deprecated_attributes(_ctx):
@@ -316,6 +317,13 @@ def _rust_library_common(ctx, crate_type):
     )
     rust_lib = ctx.actions.declare_file(rust_lib_name)
 
+    rust_metadata = None
+    if can_build_metadata(toolchain, ctx, crate_type):
+        rust_metadata = ctx.actions.declare_file(
+            paths.replace_extension(rust_lib_name, ".rmeta"),
+            sibling = rust_lib,
+        )
+
     deps = transform_deps(ctx.attr.deps)
     proc_macro_deps = transform_deps(ctx.attr.proc_macro_deps + get_import_macro_deps(ctx))
 
@@ -332,6 +340,7 @@ def _rust_library_common(ctx, crate_type):
             proc_macro_deps = depset(proc_macro_deps),
             aliases = ctx.attr.aliases,
             output = rust_lib,
+            metadata = rust_metadata,
             edition = get_edition(ctx.attr, toolchain, ctx.label),
             rustc_env = ctx.attr.rustc_env,
             is_test = False,