support static linking of ctranslate2 (#148)

* support static linking of ctranslate2

* update

* remove submodule rust-cxx-cmake-bridge

* support alwayslink with whole-archive

* update

* move export_libs

* update docker config

* update ctranslate2

* remove

* update

* update build.rs

* parse external libs

* cleanup

* add cargo fmt

crates/ctranslate2-bindings/.gitignore

@@ -1,2 +1,3 @@
 /target
 /Cargo.lock
+/build

crates/ctranslate2-bindings/CMakeLists.txt

@@ -0,0 +1,16 @@
+cmake_minimum_required(VERSION 3.7)
+
+project(ctranslate2_bindings)
+
+add_subdirectory(CTranslate2)
+
+add_library(dummy
+  src/dummy.cc
+)
+
+target_link_libraries(dummy
+  PRIVATE ctranslate2
+)
+
+include(cmake/export_libs.cmake)
+export_all_target_libs(dummy)

crates/ctranslate2-bindings/Cargo.toml

@@ -12,3 +12,4 @@ tokenizers = "0.13.3"
 bindgen = "0.53.1"
 cxx-build = "1.0"
 cmake = "0.1"
+rust-cxx-cmake-bridge = { path = "../rust-cxx-cmake-bridge" }

crates/ctranslate2-bindings/build.rs

@@ -1,21 +1,15 @@
 use cmake::Config;
+use rust_cxx_cmake_bridge::read_cmake_generated;
 
 fn main() {
-    let mut config = Config::new("CTranslate2");
+    let mut config = Config::new(".");
     config
         .define("CMAKE_BUILD_TYPE", "Release")
         .define("BUILD_CLI", "OFF")
-        .define("BUILD_SHARED_LIBS", "ON")
-        .define("CMAKE_INSTALL_RPATH_USE_LINK_PATH", "ON");
+        .define("CMAKE_INSTALL_RPATH_USE_LINK_PATH", "ON")
+        .define("BUILD_SHARED_LIBS", "OFF");
 
-    if cfg!(target_os = "macos") {
-        config
-            .define("CMAKE_OSX_ARCHITECTURES", "arm64")
-            .define("WITH_ACCELERATE", "ON")
-            .define("WITH_MKL", "OFF")
-            .define("OPENMP_RUNTIME", "NONE")
-            .define("WITH_RUY", "ON");
-    } else if cfg!(target_os = "linux") {
+    if cfg!(target_os = "linux") {
         config
             .define("WITH_CUDA", "ON")
             .define("WITH_CUDNN", "ON")
@@ -24,16 +18,26 @@ fn main() {
             .define("OPENMP_RUNTIME", "COMP")
             .cxxflag("-msse4.1")
             .define("CUDA_NVCC_FLAGS", "-Xfatbin=-compress-all")
-            .define("CUDA_ARCH_LIST", "Common");
-    }
+            .define("CUDA_ARCH_LIST", "Common")
+    } else if cfg!(target_os = "macos") {
+        config
+            .define("CMAKE_OSX_ARCHITECTURES", "arm64")
+            .define("WITH_ACCELERATE", "ON")
+            .define("WITH_MKL", "OFF")
+            .define("OPENMP_RUNTIME", "NONE")
+            .define("WITH_RUY", "ON")
+    } else {
+        panic!("Invalid target")
+    };
 
     let dst = config.build();
 
-    println!(
-        "cargo:rustc-link-search=native={}",
-        dst.join("lib").display()
-    );
-    println!("cargo:rustc-link-lib=ctranslate2");
+    // Read static lib from generated deps.
+    let cmake_generated_libs_str = std::fs::read_to_string(
+        &format!("/{}/build/cmake_generated_libs", dst.display()).to_string(),
+    )
+    .unwrap();
+    read_cmake_generated(&cmake_generated_libs_str);
 
     // Tell cargo to invalidate the built crate whenever the wrapper changes
     println!("cargo:rerun-if-changed=include/ctranslate2.h");

crates/ctranslate2-bindings/cmake/debug_cmake.sh

@@ -0,0 +1,25 @@
+#! /bin/bash
+
+set -e
+set -x
+
+UNAME="$(uname -s)"
+case "${UNAME}" in
+    Linux*)     MACHINE=linux;;
+    Darwin*)    MACHINE=macos;;
+    *)          exit 1;;
+esac
+
+rm -rf build
+mkdir build && cd build
+
+if [[ "$MACHINE" == "macos" ]]; then
+CMAKE_EXTRA_OPTIONS='-DCMAKE_OSX_ARCHITECTURES=arm64 -DWITH_ACCELERATE=ON -DWITH_MKL=OFF -DOPENMP_RUNTIME=NONE -DWITH_RUY=ON'
+elif [[ "$MACHINE" == "linux" ]]; then
+CMAKE_EXTRA_OPTIONS='-DWITH_CUDA=ON -DWITH_CUDNN=ON -DWITH_MKL=ON -DWITH_DNNL=ON -DOPENMP_RUNTIME=COMP -DCUDA_NVCC_FLAGS=-Xfatbin=-compress-all -DCUDA_ARCH_LIST=Common -DCXXFLAGS=-msse4.1'
+fi
+
+
+cmake -DBULID_SHARED_LIBS=OFF -DCMAKE_BUILD_TYPE=Release -DBUILD_CLI=OFF -DCMAKE_INSTALL_RPATH_USE_LINK_PATH=ON $CMAKE_EXTRA_OPTIONS ..
+
+"$@"

crates/ctranslate2-bindings/cmake/export_libs.cmake

@@ -0,0 +1,98 @@
+################################################################################
+
+# WARNING: to list the system libraries(ie IMPORTED) you MUST set:
+# set_target_properties(your_lib PROPERTIES IMPORTED_GLOBAL TRUE)
+# just after the find_package call
+# cf https://gitlab.kitware.com/cmake/cmake/-/issues/17256
+#
+# https://stackoverflow.com/questions/32756195/recursive-list-of-link-libraries-in-cmake
+# https://stackoverflow.com/questions/32197663/how-can-i-remove-the-the-location-property-may-not-be-read-from-target-error-i
+function(_get_link_libraries OUTPUT_LIST TARGET)
+    list(APPEND VISITED_TARGETS ${TARGET})
+
+    # DO NOT switch on IMPORTED or not
+    # An INTERFACE library CAN have LINK_LIBRARIES!
+    # get_target_property(IMPORTED ${TARGET} IMPORTED)
+    set(LIBS "")
+    get_target_property(LIBS_1 ${TARGET} INTERFACE_LINK_LIBRARIES)
+    get_target_property(LIBS_2 ${TARGET} LINK_LIBRARIES)
+    list(APPEND LIBS ${LIBS_1} ${LIBS_2})
+
+    set(LIB_FILES "")
+
+    foreach(LIB ${LIBS})
+        if (TARGET ${LIB})
+            list(FIND VISITED_TARGETS ${LIB} VISITED)
+            if (${VISITED} EQUAL -1)
+                # OLD: get_target_property(LIB_FILE ${LIB} LOCATION)
+                # NEW:
+                _get_link_libraries(LINK_LIB_FILES ${LIB})
+                set(LIB_FILE ${LIB})
+                list(APPEND LIB_FILES ${LINK_LIB_FILES})
+                list(APPEND LIB_FILES ${LIB_FILE})
+            endif()
+        elseif(EXISTS ${LIB})
+          set(LIB_FILE ${LIB})
+          list(APPEND LIB_FILES ${LIB_FILE})
+        endif()
+    endforeach()
+
+    set(VISITED_TARGETS ${VISITED_TARGETS} PARENT_SCOPE)
+    set(${OUTPUT_LIST} ${LIB_FILES} PARENT_SCOPE)
+endfunction()
+
+################################################################################
+
+function(export_all_target_libs TARGET)
+    # NOTE: get_target_property(CIRCUIT_LIB_LINK_LIBRARIES a_target LINK_LIBRARIES) is NOT transitive
+    # This function will return eg: "$<TARGET_FILE:rust_cxx>;$<TARGET_FILE:circuit_lib>;"
+    # b/c generator expression are evaluated LATER
+    # cf https://stackoverflow.com/questions/59226127/cmake-generator-expression-how-to-get-target-file-property-on-list-of-targets
+    set(ALL_LINK_LIBRARIES "")
+    _get_link_libraries(ALL_LINK_LIBRARIES ${TARGET})
+
+    message(STATUS "ALL_LINK_LIBRARIES : ${ALL_LINK_LIBRARIES}")
+
+    set(ALL_LIBS "")
+    set(ALL_EXTERNAL_LIBS "")
+    # TODO move that back into get_link_libraries
+    # NOTE: we MUST do it in 2 steps:
+    # - collect all the LINK_LIBRARIES recursively
+    # - loop on those and get their TARGET_FILE (if not INTERFACE_LIBRARY)
+    # That is b/c in get_link_libraries a INTERFACE_LIBRARY CAN have link_libraries
+    # but we CAN NOT evaluate generator expressions at this time.
+    foreach(LIB ${ALL_LINK_LIBRARIES})
+        # MUST skip INTERFACE else:
+        # CMake Error at src/CMakeLists.txt:136 (add_custom_command):
+        # Error evaluating generator expression:
+        #   $<TARGET_FILE:rust_cxx>
+        # Target "rust_cxx" is not an executable or library.
+        # SHARED_LIBRARY,INTERFACE_LIBRARY,STATIC_LIBRARY
+        #
+        if (TARGET ${LIB})
+            get_target_property(LIB_TYPE ${LIB} TYPE)
+            message(STATUS "LIB_TYPE : ${LIB} = ${LIB_TYPE}")
+
+            if(NOT ${LIB_TYPE} STREQUAL "INTERFACE_LIBRARY")
+                set(LIB_FILE $<TARGET_FILE:${LIB}>)
+                list(APPEND ALL_LIBS ${LIB_FILE})
+            endif()
+        elseif(EXISTS ${LIB})
+            set(LIB_FILE ${LIB})
+            message(STATUS "LIB_TYPE : ${LIB} = EXTERNAL")
+            list(APPEND ALL_LIBS ${LIB_FILE})
+        endif()
+    endforeach()  # LIB ${ALL_LIBS}
+
+    message(STATUS "ALL_LIBS : ${ALL_LIBS}")
+
+    # add_custom_command(ie echoing only to stdout) works but more difficult to get from build.rs
+    # b/c when there is "ninja: no work to do" it will NOT echo on the console
+    add_custom_command(
+        TARGET ${TARGET}
+        POST_BUILD
+        COMMAND ${CMAKE_COMMAND} -E echo ${ALL_LIBS} > ${CMAKE_CURRENT_BINARY_DIR}/cmake_generated_libs
+        # OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/cmake_generated_libs
+        VERBATIM
+    )
+endfunction(export_all_target_libs)

crates/rust-cxx-cmake-bridge/Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "rust-cxx-cmake-bridge"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]