Use our own googletest rather than the bundled one.
Get NNPACK to use our own PeachPy rather than the bundled one.

diff --git a/cmake/Dependencies.cmake b/cmake/Dependencies.cmake
index 5d57b9ca78..620cca4e60 100644
--- a/cmake/Dependencies.cmake
+++ b/cmake/Dependencies.cmake
@@ -644,11 +644,6 @@ if(BUILD_TEST OR BUILD_MOBILE_BENCHMARK OR BUILD_MOBILE_TEST)
   # this shouldn't be necessary anymore.
   get_property(INC_DIR_temp DIRECTORY PROPERTY INCLUDE_DIRECTORIES)
   set_property(DIRECTORY PROPERTY INCLUDE_DIRECTORIES "")
-  add_subdirectory(${CMAKE_CURRENT_LIST_DIR}/../third_party/googletest)
-  set_property(DIRECTORY PROPERTY INCLUDE_DIRECTORIES ${INC_DIR_temp})
-
-  include_directories(BEFORE SYSTEM ${CMAKE_CURRENT_LIST_DIR}/../third_party/googletest/googletest/include)
-  include_directories(BEFORE SYSTEM ${CMAKE_CURRENT_LIST_DIR}/../third_party/googletest/googlemock/include)
 
   # We will not need to test benchmark lib itself.
   set(BENCHMARK_ENABLE_TESTING OFF CACHE BOOL "Disable benchmark testing as we don't need it.")
@@ -1485,7 +1480,7 @@ if(CAFFE2_CMAKE_BUILDING_WITH_MAIN_REPO AND NOT INTERN_DISABLE_ONNX)
     endif()
     set_property(TARGET onnx_proto PROPERTY IMPORTED_LOCATION ${ONNX_PROTO_LIBRARY})
     message("-- Found onnx: ${ONNX_LIBRARY} ${ONNX_PROTO_LIBRARY}")
-    list(APPEND Caffe2_DEPENDENCY_LIBS onnx_proto onnx)
+    list(APPEND Caffe2_DEPENDENCY_LIBS onnx_proto onnx onnx_optimizer)
   endif()
   include_directories(${FOXI_INCLUDE_DIRS})
   list(APPEND Caffe2_DEPENDENCY_LIBS foxi_loader)

diff --git a/caffe2/CMakeLists.txt b/caffe2/CMakeLists.txt
index 50ebb224ce..5953d9ddf7 100644
--- a/caffe2/CMakeLists.txt
+++ b/caffe2/CMakeLists.txt
@@ -1632,7 +1632,7 @@ if(BUILD_TEST)
         if(NOT MSVC)
           add_executable(${test_name}_${CPU_CAPABILITY} "${test_src}" ../aten/src/ATen/native/quantized/affine_quantizer_base.cpp)
           # TODO: Get rid of c10 dependency (which is only needed for the implementation of AT_ERROR)
-          target_link_libraries(${test_name}_${CPU_CAPABILITY} c10 sleef gtest_main)
+          target_link_libraries(${test_name}_${CPU_CAPABILITY} c10 sleef gtest_main gtest)
           if(USE_FBGEMM)
             target_link_libraries(${test_name}_${CPU_CAPABILITY} fbgemm)
           endif()
@@ -1655,7 +1655,7 @@ if(BUILD_TEST)
   foreach(test_src ${Caffe2_CPU_TEST_SRCS})
     get_filename_component(test_name ${test_src} NAME_WE)
     add_executable(${test_name} "${test_src}")
-    target_link_libraries(${test_name} torch_library gtest_main)
+    target_link_libraries(${test_name} torch_library gtest_main gtest)
     target_include_directories(${test_name} PRIVATE $<INSTALL_INTERFACE:include>)
     target_include_directories(${test_name} PRIVATE $<BUILD_INTERFACE:${CMAKE_BINARY_DIR}/include>)
     target_include_directories(${test_name} PRIVATE ${Caffe2_CPU_INCLUDE})
@@ -1673,7 +1673,7 @@ if(BUILD_TEST)
     foreach(test_src ${Caffe2_GPU_TEST_SRCS})
       get_filename_component(test_name ${test_src} NAME_WE)
       cuda_add_executable(${test_name} "${test_src}")
-      target_link_libraries(${test_name} torch_library gtest_main)
+      target_link_libraries(${test_name} torch_library gtest_main gtest)
       target_include_directories(${test_name} PRIVATE $<INSTALL_INTERFACE:include>)
       target_include_directories(${test_name} PRIVATE ${Caffe2_CPU_INCLUDE})
       add_test(NAME ${test_name} COMMAND $<TARGET_FILE:${test_name}>)
@@ -1691,7 +1691,7 @@ if(BUILD_TEST)
     foreach(test_src ${Caffe2_VULKAN_TEST_SRCS})
       get_filename_component(test_name ${test_src} NAME_WE)
       add_executable(${test_name} "${test_src}")
-      target_link_libraries(${test_name} torch_library gtest_main)
+      target_link_libraries(${test_name} torch_library gtest_main gtest)
       target_include_directories(${test_name} PRIVATE $<INSTALL_INTERFACE:include>)
       target_include_directories(${test_name} PRIVATE ${Caffe2_CPU_INCLUDE})
       add_test(NAME ${test_name} COMMAND $<TARGET_FILE:${test_name}>)
@@ -1709,7 +1709,7 @@ if(BUILD_TEST)
     foreach(test_src ${Caffe2_HIP_TEST_SRCS})
       get_filename_component(test_name ${test_src} NAME_WE)
       add_executable(${test_name} "${test_src}")
-      target_link_libraries(${test_name} torch_library gtest_main)
+      target_link_libraries(${test_name} torch_library gtest_main gtest)
       target_include_directories(${test_name} PRIVATE $<INSTALL_INTERFACE:include>)
       target_include_directories(${test_name} PRIVATE ${Caffe2_CPU_INCLUDE} ${Caffe2_HIP_INCLUDE})
       target_compile_options(${test_name} PRIVATE ${HIP_CXX_FLAGS})

diff --git a/torch/lib/c10d/test/CMakeLists.txt b/torch/lib/c10d/test/CMakeLists.txt
index b74d4b65f7..fc7c207505 100644
--- a/torch/lib/c10d/test/CMakeLists.txt
+++ b/torch/lib/c10d/test/CMakeLists.txt
@@ -16,24 +16,24 @@ function(c10d_add_test test_src)
   add_test(NAME ${test_name} COMMAND $<TARGET_FILE:${test_name}>)
 endfunction()
 
-c10d_add_test(FileStoreTest.cpp c10d gtest_main)
-c10d_add_test(TCPStoreTest.cpp c10d gtest_main)
+c10d_add_test(FileStoreTest.cpp c10d gtest_main gtest)
+c10d_add_test(TCPStoreTest.cpp c10d gtest_main gtest)
 if(NOT WIN32)
-  c10d_add_test(HashStoreTest.cpp c10d gtest_main)
+  c10d_add_test(HashStoreTest.cpp c10d gtest_main gtest)
 endif()
 
 if(USE_CUDA)
   if(USE_C10D_GLOO)
-    c10d_add_test(ProcessGroupGlooTest.cpp c10d c10d_cuda_test gtest_main)
-    c10d_add_test(ProcessGroupGlooAsyncTest.cpp c10d c10d_cuda_test gtest_main)
+    c10d_add_test(ProcessGroupGlooTest.cpp c10d c10d_cuda_test gtest_main gtest)
+    c10d_add_test(ProcessGroupGlooAsyncTest.cpp c10d c10d_cuda_test gtest_main gtest)
   endif()
   if(USE_C10D_NCCL)
-    c10d_add_test(ProcessGroupNCCLTest.cpp c10d c10d_cuda_test gtest_main)
+    c10d_add_test(ProcessGroupNCCLTest.cpp c10d c10d_cuda_test gtest_main gtest)
     c10d_add_test(ProcessGroupNCCLErrorsTest.cpp c10d c10d_cuda_test
-        gtest_main)
+        gtest_main gtest)
   endif()
 else()
   if(USE_C10D_GLOO)
-    c10d_add_test(ProcessGroupGlooTest.cpp c10d gtest_main)
+    c10d_add_test(ProcessGroupGlooTest.cpp c10d gtest_main gtest)
   endif()
 endif()

diff --git a/cmake/External/nnpack.cmake b/cmake/External/nnpack.cmake
index a41343cbb5..6075bdd0a4 100644
--- a/cmake/External/nnpack.cmake
+++ b/cmake/External/nnpack.cmake
@@ -40,7 +40,7 @@ endif()
 # (3) Android, iOS, Linux, macOS - supported
 ##############################################################################
 
-if(ANDROID OR IOS OR ${CMAKE_SYSTEM_NAME} STREQUAL "Linux" OR ${CMAKE_SYSTEM_NAME} STREQUAL "Darwin")
+if(FALSE)
   message(STATUS "Brace yourself, we are building NNPACK")
   set(CAFFE2_THIRD_PARTY_ROOT ${PROJECT_SOURCE_DIR}/third_party)
 
@@ -114,6 +114,5 @@ endif()
 # (4) Catch-all: not supported.
 ##############################################################################
 
-message(WARNING "Unknown platform - I don't know how to build NNPACK. "
-                "See cmake/External/nnpack.cmake for details.")
-set(USE_NNPACK OFF)
+set(NNPACK_FOUND TRUE)
+set(USE_NNPACK ON)