[rust] upstreaming rust/cxx integration

.bazelrc

@@ -143,6 +143,7 @@ build:limited-dbg-info --copt='-g1' --copt="-fdebug-info-for-profiling"
 
 # Miscellaneous platform-independent options
 build --@capnp-cpp//src/kj:openssl=True --@capnp-cpp//src/kj:zlib=True --@capnp-cpp//src/kj:brotli=True
+build --@capnp-cpp//src/capnp:gen_rust=True
 build --cxxopt="-fbracket-depth=512" --host_cxxopt="-fbracket-depth=512"
 build --@capnp-cpp//src/capnp:gen_rust=True
 
@@ -152,13 +153,11 @@ build --@capnp-cpp//src/capnp:gen_rust=True
 # improvement to build speed and Rust code size.
 # Using extra_rustc_flag for non-exec flags so they can be overwritten selectively.
 build --@rules_rust//:extra_rustc_flag=-Cembed-bitcode=n
-build --@rules_rust//:extra_rustc_flag=-Cpanic=abort
 build --@rules_rust//:extra_rustc_flag=-Cdebug-assertions=n
-build --@rules_rust//:extra_exec_rustc_flags=-C,panic=abort,-C,debug-assertions=n,-C,embed-bitcode=n
+build --@rules_rust//:extra_exec_rustc_flags=-C,debug-assertions=n,-C,embed-bitcode=n
 
 # We default to not enabling debug assertions and unwinding for Rust. For debug builds this is not
 # the right setting, but unfortunately we can't set that directly.
-build:rust-debug --@rules_rust//:extra_rustc_flag=-Cpanic=unwind
 build:rust-debug --@rules_rust//:extra_rustc_flag=-Cdebug-assertions=y
 # Use the equivalent of -g/-g2 for Rust here, this is necessary to get qualified stack traces while
 # -Zdebug-info-for-profiling is unavailable. Unlike gcc/clang, Rust defaults to -g3 otherwise.

.github/workflows/release.yml

@@ -105,6 +105,8 @@ jobs:
       - name: Setup Windows
         if: runner.os == 'Windows'
         run: |
+          git config --global core.symlinks true
+          git config --show-scope --show-origin core.symlinks
           # Set a custom output root directory to avoid long file name issues.
           [System.IO.File]::WriteAllLines((Join-Path -Path $env:USERPROFILE -ChildPath '.bazelrc'), 'startup --output_user_root=C:/tmp')
       - name: Configure download mirrors

.github/workflows/test.yml

@@ -117,6 +117,8 @@ jobs:
         if: matrix.os.name == 'windows'
         # Set a custom output root directory to avoid long file name issues.
         run: |
+          git config --global core.symlinks true
+          git config --show-scope --show-origin core.symlinks
           [System.IO.File]::WriteAllLines((Join-Path -Path $env:USERPROFILE -ChildPath '.bazelrc'), 'startup --output_user_root=C:/tmp')
       - name: Configure download mirrors
         shell: bash

WORKSPACE

@@ -190,7 +190,7 @@ rust_register_toolchains(
     # also avoids registering support for the wasm32-unknown-unknown and wasm32-wasi targets, which
     # are otherwise added by default.
     extra_target_triples = ["x86_64-apple-darwin"],
-    versions = ["1.81.0"],  # LLVM 18
+    versions = ["1.82.0"],  # LLVM 19
 )
 
 load("@rules_rust//crate_universe:repositories.bzl", "crate_universe_dependencies")

build/deps/build_deps.jsonc

@@ -72,6 +72,11 @@
       "file_type": "executable",
       "downloaded_file_path": "downloaded.exe"
     },
+    {
+      "name": "cxxbridge-cmd",
+      "type": "crate",
+      "build_file": "//deps/rust:BUILD.cxxbridge-cmd"
+    },
     {
       "name": "aspect_rules_esbuild",
       "type": "github_release",

build/deps/gen/build_deps.bzl

@@ -11,6 +11,7 @@ load("@//build/deps:gen/dep_cargo_bazel_linux_x64.bzl", "dep_cargo_bazel_linux_x
 load("@//build/deps:gen/dep_cargo_bazel_macos_arm64.bzl", "dep_cargo_bazel_macos_arm64")
 load("@//build/deps:gen/dep_cargo_bazel_macos_x64.bzl", "dep_cargo_bazel_macos_x64")
 load("@//build/deps:gen/dep_cargo_bazel_win_x64.bzl", "dep_cargo_bazel_win_x64")
+load("@//build/deps:gen/dep_cxxbridge_cmd.bzl", "dep_cxxbridge_cmd")
 load("@//build/deps:gen/dep_rules_pkg.bzl", "dep_rules_pkg")
 load("@//build/deps:gen/dep_rules_python.bzl", "dep_rules_python")
 load("@//build/deps:gen/dep_rules_rust.bzl", "dep_rules_rust")
@@ -25,6 +26,7 @@ def deps_gen():
     dep_cargo_bazel_macos_x64()
     dep_cargo_bazel_macos_arm64()
     dep_cargo_bazel_win_x64()
+    dep_cxxbridge_cmd()
     dep_aspect_rules_esbuild()
     dep_rules_pkg()
     dep_aspect_bazel_lib()

build/deps/gen/dep_capnp_cpp.bzl

@@ -2,11 +2,11 @@
 
 load("@//:build/http.bzl", "http_archive")
 
-URL = "https://github.com/capnproto/capnproto/tarball/3c849db4caa127f75fefcfdc9e7105c8a62cbed0"
-STRIP_PREFIX = "capnproto-capnproto-3c849db/c++"
-SHA256 = "acc108b7cb8d3ef6fd37da19529b5a97940e49c75676bb3c8749e32478628265"
+URL = "https://github.com/capnproto/capnproto/tarball/0fb157fb00f8f2cacf23751f56d12bf6c8459f6a"
+STRIP_PREFIX = "capnproto-capnproto-0fb157f/c++"
+SHA256 = "15bc213e1869c84d2b02ad4cde61e01c0ee264c77a2af055a41581091c851b9c"
 TYPE = "tgz"
-COMMIT = "3c849db4caa127f75fefcfdc9e7105c8a62cbed0"
+COMMIT = "0fb157fb00f8f2cacf23751f56d12bf6c8459f6a"
 
 def dep_capnp_cpp():
     http_archive(

build/deps/gen/dep_cxxbridge_cmd.bzl

@@ -0,0 +1,19 @@
+# WARNING: THIS FILE IS AUTOGENERATED BY update-deps.py DO NOT EDIT
+
+load("@//:build/http.bzl", "http_archive")
+
+URL = "https://crates.io/api/v1/crates/cxxbridge-cmd/1.0.129/download"
+STRIP_PREFIX = "cxxbridge-cmd-1.0.129"
+SHA256 = "c089cc7133ae878b2b6993a85f006b5d13e6031a72da721d7dce98a17cb72b72"
+TYPE = "tgz"
+VERSION = "1.0.129"
+
+def dep_cxxbridge_cmd():
+    http_archive(
+        name = "cxxbridge-cmd",
+        url = URL,
+        strip_prefix = STRIP_PREFIX,
+        type = TYPE,
+        sha256 = SHA256,
+        build_file = "//deps/rust:BUILD.cxxbridge-cmd",
+    )

build/wd_rust_crate.bzl

@@ -0,0 +1,126 @@
+load("@rules_rust//rust:defs.bzl", "rust_library", "rust_test")
+
+def rust_cxx_include(name, visibility = [], include_prefix = None):
+    native.genrule(
+        name = "%s/generated" % name,
+        outs = ["cxx.h"],
+        cmd = "$(location @cxxbridge-cmd//:cxxbridge-cmd) --header > \"$@\"",
+        tools = ["@cxxbridge-cmd//:cxxbridge-cmd"],
+    )
+
+    native.cc_library(
+        name = name,
+        hdrs = ["cxx.h"],
+        include_prefix = include_prefix,
+        visibility = visibility,
+    )
+
+def _rust_cxx_bridge(
+        name,
+        src,
+        hdrs = [],
+        deps = [],
+        visibility = [],
+        strip_include_prefix = None,
+        include_prefix = None):
+    native.genrule(
+        name = "%s/generated" % name,
+        srcs = [src],
+        outs = [
+            src + ".h",
+            src + ".cc",
+        ],
+        cmd = "$(location @cxxbridge-cmd//:cxxbridge-cmd) $(location %s) -o $(location %s.h) -o $(location %s.cc)" % (src, src, src),
+        tools = ["@cxxbridge-cmd//:cxxbridge-cmd"],
+    )
+
+    native.cc_library(
+        name = name,
+        srcs = [src + ".cc"],
+        hdrs = [src + ".h"] + hdrs,
+        strip_include_prefix = strip_include_prefix,
+        include_prefix = include_prefix,
+        linkstatic = True,
+        deps = deps,
+        visibility = visibility,
+    )
+
+def wd_rust_crate(
+        name,
+        cxx_bridge_src = None,
+        deps = [],
+        proc_macro_deps = [],
+        data = [],
+        test_env = {},
+        test_tags = [],
+        test_deps = [],
+        test_proc_macro_deps = [],
+        cxx_bridge_deps = [],
+        visibility = None):
+    """Define rust crate.
+
+    Args:
+        name: crate name.
+        cxx_bridge_src: (optional) .rs source file with cxx ffi bridge definition. The rule will
+            generation additional<name>@cxx c++ library with cxx bindings if this is set.
+        deps: crate dependencies: rust crates or c/c++ libraries.
+        visibility: crate visibility.
+        data: additional data files.
+        proc_macro_deps: proc_macro dependencies.
+        rustc_env: rustc environment variables,
+        test_env: additional test environment variable.
+        test_tags: additional test tags.
+        test_deps: test-only dependencies.
+        test_proc_macro_deps: test-only proc_macro dependencies.
+    """
+    srcs = native.glob(["**/*.rs"])
+    crate_name = name.replace("-", "_")
+
+    if cxx_bridge_src:
+        hdrs = native.glob(["**/*.h"], allow_empty = True)
+
+        _rust_cxx_bridge(
+            name = name + "@cxx",
+            src = cxx_bridge_src,
+            hdrs = hdrs,
+            include_prefix = "rust/" + name,
+            strip_include_prefix = "",
+            # Not applying visibility here – if you import the cxxbridge header, you will likely
+            # also need the rust library itself to avoid linker errors.
+            deps = cxx_bridge_deps + [
+                "@crates_vendor//:cxx",
+                "//src/rust/cxx-integration:cxx-include",
+            ],
+        )
+
+        deps.append("@crates_vendor//:cxx")
+        deps.append(name + "@cxx")
+
+    crate_features = []
+
+    rust_library(
+        name = name,
+        crate_name = crate_name,
+        srcs = srcs,
+        deps = deps,
+        visibility = visibility,
+        data = data,
+        proc_macro_deps = proc_macro_deps,
+        crate_features = crate_features,
+    )
+
+    rust_test(
+        name = name + "_test",
+        crate = ":" + name,
+        env = {
+            "RUST_BACKTRACE": "1",
+            # rust test runner captures stderr by default, which makes debugging tests very hard
+            "RUST_TEST_NOCAPTURE": "1",
+            # our tests are usually very heavy and do not support concurrent invocation
+            "RUST_TEST_THREADS": "1",
+        } | test_env,
+        tags = test_tags,
+        crate_features = crate_features,
+        deps = test_deps,
+        proc_macro_deps = test_proc_macro_deps,
+    )

deps/rust/BUILD.bazel

@@ -79,7 +79,9 @@ crates_vendor(
 cc_library(
     name = "runtime",
     linkopts = select({
-        "@platforms//os:windows": ["ntdll.lib"],
+        "@platforms//os:windows": [
+            "ntdll.lib",
+        ],
         "//conditions:default": [],
     }),
     visibility = ["//visibility:public"],

deps/rust/BUILD.cxxbridge-cmd

@@ -0,0 +1,19 @@
+load("@rules_rust//rust:defs.bzl", "rust_binary")
+
+# Build file for cxxbridge-cmd tool.
+
+rust_binary(
+    name = "cxxbridge-cmd",
+    srcs = glob(["src/**/*.rs"]),
+    data = ["src/gen/include/cxx.h"],
+    edition = "2021",
+    visibility = ["//visibility:public"],
+    deps = [
+        "@crates_vendor//:clap",
+        "@crates_vendor//:codespan-reporting",
+        "@crates_vendor//:cxx",
+        "@crates_vendor//:proc-macro2",
+        "@crates_vendor//:quote",
+        "@crates_vendor//:syn",
+    ],
+)