build(cmake): link migrated Rust code into native libraries

Build a configuration-matched Cargo static library during CMake builds and join its object members into the generated static libzstd archive. A single flattened archive avoids C-to-Rust and Rust-to-C archive-order failures for external consumers. Shared builds whole-archive the Cargo output so Rust-only public ABI exports remain visible. The configuration also follows partial compression and decompression builds, forced HUF modes, and supported 32-bit Linux targets. Dedicated CTest smoke consumers cover both linkage forms. Test Plan: - configure and build fresh static and shared CMake smoke targets - ctest -R 'rustLibSmoke(Static|Shared)' --output-on-failure - cargo clippy, cargo clippy --benches, cargo clippy --tests, and nightly fmt - validate partial, forced-HUF, i686, install, and incremental build paths Refs: build/cmake/lib/merge_rust_archive.cmake
2026-07-10 21:55:40 +02:00
parent 0a6a5f5267
commit 22ec52d5ec
3 changed files with 275 additions and 1 deletions
@@ -0,0 +1,82 @@
+# ################################################################
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under both the BSD-style license (found in the
+# LICENSE file in the root directory of this source tree) and the GPLv2 (found
+# in the COPYING file in the root directory of this source tree).
+# ################################################################
+
+# Merge the Cargo static library into CMake's libzstd static archive.  Keeping
+# the object members in one archive matters: C objects call migrated Rust
+# functions and Rust objects call C helpers, so two separate archives are
+# sensitive to the consumer linker's archive scan order.
+
+foreach(_zstd_required ARCHIVER RUST_ARCHIVE TARGET_ARCHIVE WORK_DIR)
+    if(NOT DEFINED ${_zstd_required})
+        message(FATAL_ERROR "${_zstd_required} is required")
+    endif()
+endforeach()
+
+file(REMOVE_RECURSE "${WORK_DIR}")
+file(MAKE_DIRECTORY "${WORK_DIR}")
+
+if(ARCHIVER_STYLE STREQUAL "MSVC")
+    # lib.exe accepts libraries as inputs and writes their object members to a
+    # new archive.  Keep the original C archive separate while it is read,
+    # because /OUT must not overwrite an input archive.
+    set(_zstd_c_archive "${WORK_DIR}/libzstd-c.lib")
+    execute_process(
+        COMMAND "${CMAKE_COMMAND}" -E copy "${TARGET_ARCHIVE}" "${_zstd_c_archive}"
+        RESULT_VARIABLE _zstd_copy_result)
+    if(NOT _zstd_copy_result EQUAL 0)
+        message(FATAL_ERROR "could not copy ${TARGET_ARCHIVE} for Rust archive merge")
+    endif()
+
+    execute_process(
+        COMMAND "${ARCHIVER}" "/OUT:${TARGET_ARCHIVE}" "${_zstd_c_archive}" "${RUST_ARCHIVE}"
+        RESULT_VARIABLE _zstd_merge_result
+        OUTPUT_VARIABLE _zstd_merge_output
+        ERROR_VARIABLE _zstd_merge_error)
+else()
+    execute_process(
+        COMMAND "${ARCHIVER}" x "${RUST_ARCHIVE}"
+        WORKING_DIRECTORY "${WORK_DIR}"
+        RESULT_VARIABLE _zstd_extract_result
+        OUTPUT_VARIABLE _zstd_extract_output
+        ERROR_VARIABLE _zstd_extract_error)
+    if(NOT _zstd_extract_result EQUAL 0)
+        message(FATAL_ERROR
+            "could not extract Rust archive ${RUST_ARCHIVE}: ${_zstd_extract_output}${_zstd_extract_error}")
+    endif()
+
+    file(GLOB _zstd_rust_objects "${WORK_DIR}/*.o" "${WORK_DIR}/*.obj")
+    if(NOT _zstd_rust_objects)
+        message(FATAL_ERROR "Rust archive ${RUST_ARCHIVE} did not contain object files")
+    endif()
+
+    execute_process(
+        COMMAND "${ARCHIVER}" q "${TARGET_ARCHIVE}" ${_zstd_rust_objects}
+        RESULT_VARIABLE _zstd_merge_result
+        OUTPUT_VARIABLE _zstd_merge_output
+        ERROR_VARIABLE _zstd_merge_error)
+endif()
+
+if(NOT _zstd_merge_result EQUAL 0)
+    message(FATAL_ERROR
+        "could not merge Rust archive ${RUST_ARCHIVE}: ${_zstd_merge_output}${_zstd_merge_error}")
+endif()
+
+if(DEFINED RANLIB AND NOT "${RANLIB}" STREQUAL "" AND NOT ARCHIVER_STYLE STREQUAL "MSVC")
+    execute_process(
+        COMMAND "${RANLIB}" "${TARGET_ARCHIVE}"
+        RESULT_VARIABLE _zstd_ranlib_result
+        OUTPUT_VARIABLE _zstd_ranlib_output
+        ERROR_VARIABLE _zstd_ranlib_error)
+    if(NOT _zstd_ranlib_result EQUAL 0)
+        message(FATAL_ERROR
+            "could not index ${TARGET_ARCHIVE}: ${_zstd_ranlib_output}${_zstd_ranlib_error}")
+    endif()
+endif()
+
+file(REMOVE_RECURSE "${WORK_DIR}")