Fix cmake Rust concurrency issues

.github/workflows/run-tests.yml

@@ -44,9 +44,6 @@ jobs:
         with:
           python-version: '3.x'
 
-      - name: Install Python dependencies
-        run: pip install tomli
-
       - name: Configure
         run: |
           mkdir build && cd build

CMakeLists.txt

@@ -64,17 +64,12 @@ if (NOT RUSTC_LLVM_VERSION STREQUAL LLVM_PACKAGE_VERSION)
 endif()
 
 include(${CMAKE_CURRENT_SOURCE_DIR}/cmake/rust-toolchain.cmake)
-
-# rule-preprocessor uses nightly
-foreach(_dir libcc2rs rules)
-  write_rust_toolchain(${CMAKE_SOURCE_DIR}/${_dir})
-endforeach()
-
 set(RUST_STAMP_FILE "${CMAKE_BINARY_DIR}/.rust-toolchain.stamp")
 
 add_custom_command(
     OUTPUT "${RUST_STAMP_FILE}"
     COMMAND rustup toolchain install ${RUST_STABLE_VERSION}
+    COMMAND rustup toolchain install ${RUST_NIGHTLY_VERSION} --component rustc-dev --component llvm-tools
     COMMAND ${CMAKE_COMMAND} -E touch "${RUST_STAMP_FILE}"
     DEPENDS "${CMAKE_CURRENT_SOURCE_DIR}/cmake/rust-toolchain.cmake"
     USES_TERMINAL
@@ -95,18 +90,18 @@ set(PYTHON_SOURCES ${PROJECT_SOURCE_DIR}/tests/lit/lit/formats/Cpp2RustTest.py)
 
 add_custom_target("format"
                   COMMAND ${CLANG_FORMAT} -i ${ALL_CXX_SOURCES}
-                  COMMAND rustup run ${RUST_STABLE_VERSION} cargo fmt --manifest-path ${PROJECT_SOURCE_DIR}/rules/Cargo.toml
-                  COMMAND rustup run ${RUST_STABLE_VERSION} cargo fmt --manifest-path ${PROJECT_SOURCE_DIR}/rule-preprocessor/Cargo.toml
-                  COMMAND rustup run ${RUST_STABLE_VERSION} cargo fmt --manifest-path ${PROJECT_SOURCE_DIR}/libcc2rs/Cargo.toml
-                  COMMAND rustup run ${RUST_STABLE_VERSION} cargo fmt --manifest-path ${PROJECT_SOURCE_DIR}/libcc2rs-macros/Cargo.toml
-                  COMMAND ${CMAKE_COMMAND} -E chdir ${PROJECT_SOURCE_DIR}/rules
-                    cargo clippy --fix --allow-dirty --allow-staged --all-targets --all-features -- -Dwarnings
-                  COMMAND ${CMAKE_COMMAND} -E chdir ${PROJECT_SOURCE_DIR}/rule-preprocessor
-                    cargo clippy --fix --allow-dirty --allow-staged --all-targets --all-features -- -Dwarnings
-                  COMMAND ${CMAKE_COMMAND} -E chdir ${PROJECT_SOURCE_DIR}/libcc2rs
-                    cargo clippy --fix --allow-dirty --allow-staged --all-targets --all-features -- -Dwarnings
-                  COMMAND ${CMAKE_COMMAND} -E chdir ${PROJECT_SOURCE_DIR}/libcc2rs-macros
-                    cargo clippy --fix --allow-dirty --allow-staged --all-targets --all-features -- -Dwarnings
+                  COMMAND cargo +${RUST_STABLE_VERSION} fmt --manifest-path ${PROJECT_SOURCE_DIR}/rules/Cargo.toml
+                  COMMAND cargo +${RUST_STABLE_VERSION}  --manifest-path ${PROJECT_SOURCE_DIR}/rule-preprocessor/Cargo.toml
+                  COMMAND cargo +${RUST_STABLE_VERSION} fmt --manifest-path ${PROJECT_SOURCE_DIR}/libcc2rs/Cargo.toml
+                  COMMAND cargo +${RUST_STABLE_VERSION} fmt --manifest-path ${PROJECT_SOURCE_DIR}/libcc2rs-macros/Cargo.toml
+                  COMMAND cargo +${RUST_STABLE_VERSION} clippy --fix --allow-dirty --allow-staged --all-targets --all-features
+                                --manifest-path ${PROJECT_SOURCE_DIR}/rules/Cargo.toml -- -Dwarnings
+                  COMMAND cargo +${RUST_STABLE_VERSION} clippy --fix --allow-dirty --allow-staged --all-targets --all-features
+                                --manifest-path chdir ${PROJECT_SOURCE_DIR}/rule-preprocessor/Cargo.toml -- -Dwarnings
+                  COMMAND cargo +${RUST_STABLE_VERSION} clippy --fix --allow-dirty --allow-staged --all-targets --all-features
+                                --manifest-path $${PROJECT_SOURCE_DIR}/libcc2rs/Cargo.toml -- -Dwarnings
+                  COMMAND cargo +${RUST_STABLE_VERSION} clippy --fix --allow-dirty --allow-staged --all-targets --all-features
+                                --manifest-path ${PROJECT_SOURCE_DIR}/libcc2rs-macros/Cargo.toml -- -Dwarnings
                   COMMAND ${RUFF} --silent check --fix ${PYTHON_SOURCES}
                   COMMAND ${RUFF} --silent format ${PYTHON_SOURCES}
                   DEPENDS "${RUST_STAMP_FILE}"
@@ -119,7 +114,7 @@ if (NOT LIT_FLAGS)
 endif()
 
 add_custom_target("check-libcc2rs"
-                  COMMAND cargo test
+                  COMMAND cargo +${RUST_STABLE_VERSION} test
                   WORKING_DIRECTORY "${PROJECT_SOURCE_DIR}/libcc2rs"
                   DEPENDS "${RUST_STAMP_FILE}"
                   USES_TERMINAL
@@ -188,12 +183,10 @@ file(GLOB_RECURSE rule_preprocessor_sources
 
 add_custom_command(
   OUTPUT ${rust_rules_ir_outputs}
-  COMMAND cargo build
-  COMMAND ${CMAKE_COMMAND} -E chdir ${PROJECT_SOURCE_DIR}/rule-preprocessor
-          ${CMAKE_COMMAND} -E env
-              CARGO_TARGET_DIR=${PROJECT_SOURCE_DIR}/rule-preprocessor/target
-              cargo run
-  WORKING_DIRECTORY "${PROJECT_SOURCE_DIR}/rules"
+  COMMAND cargo +${RUST_STABLE_VERSION} build --release --manifest-path "${PROJECT_SOURCE_DIR}/rules/Cargo.toml"
+  COMMAND ${CMAKE_COMMAND} -E env
+          CARGO_TARGET_DIR="${CMAKE_CURRENT_BINARY_DIR}/target_preprocessor"
+          cargo +${RUST_NIGHTLY_VERSION} run --manifest-path "${PROJECT_SOURCE_DIR}/rule-preprocessor/Cargo.toml"
   DEPENDS ${rust_rules_inputs} ${rule_preprocessor_sources} "${RUST_STAMP_FILE}"
   VERBATIM
 )

README.md

@@ -36,8 +36,7 @@ while satisfying Rust's borrow checker through checked run-time operations.
 On Ubuntu, install the required dependencies with:
 
 ```bash
-sudo apt install libclang-22-dev clang++-22 ninja-build cmake python3-tomli
-curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y --default-toolchain 1.95.0
+sudo apt install libclang-22-dev clang++-22 ninja-build cmake
 curl -LsSf https://astral.sh/ruff/install.sh | sh
 ```
 

cmake/rust-toolchain.cmake

@@ -1,12 +1,2 @@
 set(RUST_STABLE_VERSION "1.95.0")
-
-function(write_rust_toolchain DIR)
-  set(_content "[toolchain]\nchannel = \"${RUST_STABLE_VERSION}\"\n")
-  set(_file ${DIR}/rust-toolchain.toml)
-  if (EXISTS ${_file})
-    file(READ ${_file} _existing)
-  endif()
-  if (NOT "${_existing}" STREQUAL "${_content}")
-    file(WRITE ${_file} ${_content})
-  endif()
-endfunction()
+set(RUST_NIGHTLY_VERSION "nightly-2026-05-13")

tests/lit/lit/formats/Cpp2RustTest.py

@@ -9,15 +9,18 @@
 import re
 import shutil
 import random
-import tomli
 
 
 def read_rust_version():
     toolchain_path = os.path.join(
-        os.path.dirname(__file__), "../../../../libcc2rs/rust-toolchain.toml"
+        os.path.dirname(__file__), "../../../../cmake/rust-toolchain.cmake"
     )
-    with open(toolchain_path, "rb") as f:
-        return tomli.load(f)["toolchain"]["channel"]
+    with open(toolchain_path, "r") as f:
+        for line in f:
+            m = re.match(r'set\(RUST_STABLE_VERSION\s+"([^"]+)', line)
+            if m:
+                return m.group(1)
+    raise Exception("could not find rust version in " + toolchain_path)
 
 
 def shared_target_dir():
@@ -170,15 +173,12 @@ def fail(str, code=fail_code):
         pkg_name = "test_" + re.sub(r"[^a-zA-Z0-9_]", "_", os.path.basename(tmp_dir))
 
         # Check if we can compile the rust file
-        with open(tmp_dir + "/rust-toolchain.toml", "w") as f:
-            f.write(f'[toolchain]\nchannel = "{self.rust_version}"\n')
         with open(tmp_dir + "/Cargo.toml", "w") as f:
             f.write(f"""
 [package]
 name = "{pkg_name}"
 version = "0.1.0"
 edition = "2021"
-rust-version = "{self.rust_version}"
 
 [[bin]]
 name = "{pkg_name}"
@@ -189,7 +189,7 @@ def fail(str, code=fail_code):
 libcc2rs = {{ path = "../../../libcc2rs" }}
 """)
 
-        cmd = ["cargo", "build", "--release", "--quiet"]
+        cmd = ["cargo", "+" + self.rust_version, "build", "--release", "--quiet"]
         _, err, returncode = lit.util.executeCommand(cmd, tmp_dir, env=cargo_env())
         if should_not_compile:
             if returncode != 0: