remove the ability to bring flatc

Author: jathu

.ci/scripts/build_llama_android.sh

@@ -60,6 +60,5 @@ build_llama_runner() {
 
     cmake --build cmake-android-out/examples/models/llama -j4 --config Release
 }
-install_flatc_from_source
 install_executorch_and_backend_lib
 build_llama_runner

.ci/scripts/utils.sh

@@ -72,25 +72,6 @@ install_pytorch_and_domains() {
   sccache --show-stats || true
 }
 
-install_flatc_from_source() {
-  # NB: This function could be used to install flatbuffer from source
-  pushd third-party/flatbuffers || return
-
-  cmake -G "Unix Makefiles" -DCMAKE_BUILD_TYPE=Release
-  if [ "$(uname)" == "Darwin" ]; then
-    CMAKE_JOBS=$(( $(sysctl -n hw.ncpu) - 1 ))
-  else
-    CMAKE_JOBS=$(( $(nproc) - 1 ))
-  fi
-  cmake --build . -j "${CMAKE_JOBS}"
-
-  # Copy the flatc binary to conda path
-  EXEC_PATH=$(dirname "$(which python)")
-  cp flatc "${EXEC_PATH}"
-
-  popd || return
-}
-
 build_executorch_runner_buck2() {
   # Build executorch runtime with retry as this step is flaky on macos CI
   retry buck2 build //examples/portable/executor_runner:executor_runner

CMakeLists.txt

@@ -471,10 +471,9 @@ cmake_dependent_option(
 #
 cmake_dependent_option(
   EXECUTORCH_BUILD_FLATC "Build the flatc executable." ON
-  "NOT FLATC_EXECUTABLE;EXECUTORCH_BUILD_HOST_TARGETS" OFF
+  "NOT FLATC_EXECUTABLE" OFF
 )
 
-
 set(FLATBUFFERS_BUILD_FLATC OFF CACHE BOOL "")
 set(FLATBUFFERS_BUILD_FLATHASH OFF CACHE BOOL "")
 set(FLATBUFFERS_BUILD_FLATLIB OFF CACHE BOOL "")
@@ -507,6 +506,9 @@ if(EXECUTORCH_BUILD_FLATC)
                -DFLATBUFFERS_BUILD_TESTS=${FLATBUFFERS_BUILD_TESTS}
                -DFLATBUFFERS_INSTALL=${FLATBUFFERS_INSTALL}
                -DCMAKE_CXX_FLAGS="-DFLATBUFFERS_MAX_ALIGNMENT=${FLATBUFFERS_MAX_ALIGNMENT}"
+               # Flags "unset" to prevent platform flags from being propagated.
+               $<$<BOOL:${CMAKE_TOOLCHAIN_IOS}>:-DCMAKE_TOOLCHAIN_FILE=>
+               $<$<BOOL:${CMAKE_TOOLCHAIN_IOS}>:-DCMAKE_OSX_SYSROOT=>
     INSTALL_COMMAND ""
     BUILD_BYPRODUCTS <BINARY_DIR>/flatc
   )
@@ -515,6 +517,8 @@ if(EXECUTORCH_BUILD_FLATC)
     # flatbuffers does not use CMAKE_BUILD_TYPE. Internally, the build forces Release
     # config, but from CMake's perspective the build type is always Debug.
     set(FLATC_EXECUTABLE ${BINARY_DIR}/$<CONFIG>/flatc.exe)
+  elseif(CMAKE_TOOLCHAIN_IOS)
+    set(FLATC_EXECUTABLE ${BINARY_DIR}/$<CONFIG>/flatc)
   else()
     set(FLATC_EXECUTABLE ${BINARY_DIR}/flatc)
   endif()
@@ -528,12 +532,7 @@ if(NOT FLATC_EXECUTABLE)
   find_program(FLATC_EXECUTABLE flatc)
 
   if(NOT FLATC_EXECUTABLE)
-    message(
-      FATAL_ERROR
-        "FLATC_EXECUTABLE must be set when EXECUTORCH_BUILD_FLATC is disabled. "
-        "Note that EXECUTORCH_BUILD_FLATC may be disabled implicitly when "
-        "cross-compiling or when EXECUTORCH_BUILD_HOST_TARGETS is disabled."
-    )
+    message(FATAL_ERROR "FLATC_EXECUTABLE must be set when EXECUTORCH_BUILD_FLATC is disabled.")
   endif()
 endif()
 

build/build_android_library.sh

@@ -12,7 +12,6 @@ OUTPUT="cmake-out"
 MODES=()
 TOOLCHAIN=""
 PYTHON=$(which python3)
-FLATC=$(which flatc)
 COREML=OFF
 CUSTOM=OFF
 MPS=OFF
@@ -83,7 +82,6 @@ usage() {
   echo "  --Release            Build Release version."
   echo "  --toolchain=FILE     CMake toolchain file. Default: '\$SOURCE_ROOT_DIR/third-party/ios-cmake/ios.toolchain.cmake'"
   echo "  --python=FILE        Python executable path. Default: Path of python3 in \$PATH"
-  echo "  --flatc=FILE         FlatBuffers Compiler executable path. Default: Path of flatc in \$PATH"
   echo "  --coreml             Build the Core ML backend."
   echo "  --custom             Build the Custom kernels."
   echo "  --mps                Build the Metal Performance Shaders backend."
@@ -113,7 +111,6 @@ for arg in "$@"; do
         ;;
       --toolchain=*) TOOLCHAIN="${arg#*=}" ;;
       --python=*) PYTHON="${arg#*=}" ;;
-      --flatc=*) FLATC="${arg#*=}" ;;
       --coreml) COREML=ON ;;
       --custom) CUSTOM=ON ;;
       --mps) MPS=ON ;;
@@ -152,7 +149,6 @@ check_command() {
 check_command cmake
 check_command rsync
 check_command "$PYTHON"
-check_command "$FLATC"
 
 echo "Building libraries"
 
@@ -173,7 +169,6 @@ cmake_build() {
         -DCMAKE_C_FLAGS="-ffile-prefix-map=$SOURCE_ROOT_DIR=/executorch -fdebug-prefix-map=$SOURCE_ROOT_DIR=/executorch" \
         -DCMAKE_CXX_FLAGS="-ffile-prefix-map=$SOURCE_ROOT_DIR=/executorch -fdebug-prefix-map=$SOURCE_ROOT_DIR=/executorch" \
         -DPYTHON_EXECUTABLE="$PYTHON" \
-        -DFLATC_EXECUTABLE="$FLATC" \
         -DEXECUTORCH_BUILD_COREML=$COREML \
         -DEXECUTORCH_BUILD_MPS=$MPS \
         -DEXECUTORCH_BUILD_XNNPACK=$XNNPACK \

build/build_apple_frameworks.sh

@@ -64,8 +64,6 @@ say "Installing Requirements"
 pip install --upgrade cmake pip setuptools wheel zstd
 
 ./install_executorch.sh --pybind coreml mps xnnpack
-export PATH="$(realpath third-party/flatbuffers/cmake-out):$PATH"
-./build/install_flatc.sh
 
 say "Installing CoreML Backend Requirements"