Optionally move setup.py/pip cmake-out to repo_root/cmake-out

.ci/scripts/utils.sh

@@ -25,9 +25,9 @@ install_executorch() {
   # Install executorch, this assumes that Executorch is checked out in the
   # current directory.
   if [[ "${1:-}" == "use-pt-pinned-commit" ]]; then
-    ./install_executorch.sh --pybind xnnpack --use-pt-pinned-commit
+    EXECUTORCH_USE_SHARED_CMAKE_OUT_FOR_SETUP=1 ./install_executorch.sh --pybind xnnpack --use-pt-pinned-commit
   else
-    ./install_executorch.sh --pybind xnnpack
+    EXECUTORCH_USE_SHARED_CMAKE_OUT_FOR_SETUP=1 ./install_executorch.sh --pybind xnnpack
   fi
   # Just print out the list of packages for debugging
   pip list

.github/workflows/pull.yml

@@ -220,9 +220,6 @@ jobs:
 
         PYTHON_EXECUTABLE=python bash .ci/scripts/setup-linux.sh "cmake"
 
-        # install pybind
-        bash install_executorch.sh --pybind xnnpack --use-pt-pinned-commit
-
         # install Llava requirements
         bash examples/models/llama/install_requirements.sh
         bash examples/models/llava/install_requirements.sh
@@ -483,9 +480,6 @@ jobs:
 
         PYTHON_EXECUTABLE=python bash .ci/scripts/setup-linux.sh "cmake"
 
-        # install pybind
-        bash install_executorch.sh --pybind xnnpack --use-pt-pinned-commit
-
         # install phi-3-mini requirements
         bash examples/models/phi-3-mini/install_requirements.sh
 
@@ -513,9 +507,6 @@ jobs:
 
         PYTHON_EXECUTABLE=python bash .ci/scripts/setup-linux.sh "cmake"
 
-        # install pybind
-        bash install_executorch.sh --pybind xnnpack --use-pt-pinned-commit
-
         # install llama requirements
         bash examples/models/llama/install_requirements.sh
 
@@ -543,9 +534,6 @@ jobs:
 
         PYTHON_EXECUTABLE=python bash .ci/scripts/setup-linux.sh "cmake"
 
-        # install pybind
-        bash install_executorch.sh --pybind xnnpack --use-pt-pinned-commit
-
         # install llama requirements
         bash examples/models/llama/install_requirements.sh
 
@@ -573,9 +561,6 @@ jobs:
 
         PYTHON_EXECUTABLE=python bash .ci/scripts/setup-linux.sh "cmake"
 
-        # install pybind
-        bash install_executorch.sh --pybind xnnpack --use-pt-pinned-commit
-
         # install llama requirements
         bash examples/models/llama/install_requirements.sh
 

.github/workflows/trunk.yml

@@ -149,8 +149,9 @@ jobs:
         CONDA_ENV=$(conda env list --json | jq -r ".envs | .[-1]")
         conda activate "${CONDA_ENV}"
 
-        source .ci/scripts/utils.sh
-        install_executorch "use-pt-pinned-commit"
+        # Intentionally avoiding utils.sh install_executorch because
+        # it opts into shared cmake-out, which breaks these builds.
+        ./install_executorch.py --pybind xnnpack --use-pt-pinned-commit
 
         .ci/scripts/setup-arm-baremetal-tools.sh
 
@@ -179,8 +180,9 @@ jobs:
         CONDA_ENV=$(conda env list --json | jq -r ".envs | .[-1]")
         conda activate "${CONDA_ENV}"
 
-        source .ci/scripts/utils.sh
-        install_executorch "use-pt-pinned-commit"
+        # Intentionally avoiding utils.sh install_executorch because
+        # it opts into shared cmake-out, which breaks these builds.
+        ./install_executorch.py --pybind xnnpack --use-pt-pinned-commit
 
         .ci/scripts/setup-arm-baremetal-tools.sh
 

setup.py

@@ -237,11 +237,11 @@ def src_path(self, installer: "InstallerBuildExt") -> Path:
         srcs = tuple(cmake_cache_dir.glob(self.src))
         if len(srcs) != 1:
             raise ValueError(
-                f"""Expected exactly one file matching '{self.src}'; found {repr(srcs)}. 
+                f"""Expected exactly one file matching '{self.src}'; found {repr(srcs)}.
 
 If that file is a CMake-built extension module file, and we are installing in editable mode, please disable the corresponding build option since it's not supported yet.
 
-Try: 
+Try:
 
 EXECUTORCH_BUILD_FLATC=OFF EXECUTORCH_BUILD_KERNELS_CUSTOM_AOT=OFF pip install -e .
 """
@@ -611,9 +611,19 @@ def run(self):
         # for multi-config generators.
         build_args += ["--config", cfg]
 
-        # Put the cmake cache under the temp directory, like
-        # "pip-out/temp.<plat>/cmake-out".
-        cmake_cache_dir = os.path.join(repo_root, self.build_temp, "cmake-out")
+        if ShouldBuild._is_env_enabled("EXECUTORCH_USE_SHARED_CMAKE_OUT_FOR_SETUP"):
+            # Share the cmake-out directory with any other cmake builds the
+            # user/developer might do, rather than hiding it under build_temp.
+            #
+            # Opt-in because there is a risk of accidentally mixing built artifacts from
+            # different build configurations, which could lead to painful debugging
+            # sessions. The upside is faster incremental cmake builds after running
+            # install_executorch.sh.
+            cmake_cache_dir = os.path.join(repo_root, "cmake-out")
+        else:
+            # Put the cmake cache under the temp directory, like
+            # "pip-out/temp.<plat>/cmake-out".
+            cmake_cache_dir = os.path.join(repo_root, self.build_temp, "cmake-out")
         self.mkpath(cmake_cache_dir)
 
         # Generate the cmake cache from scratch to ensure that the cache state