diff --git a/CMakeLists.txt b/CMakeLists.txt
index a6efb3d4623..4c1b8e2ec71 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -146,10 +146,9 @@ if(EXECUTORCH_ENABLE_EVENT_TRACER)
 endif()
 
 # -ffunction-sections -fdata-sections: breaks function and data into sections so
-# they can be properly gc'd. -s: strip symbol. -fno-exceptions -fno-rtti:
-# disables exceptions and runtime type.
+# they can be properly gc'd. -s: strip symbol.
 set(CMAKE_CXX_FLAGS_RELEASE
-    "-ffunction-sections -fdata-sections -fno-exceptions -fno-rtti ${CMAKE_CXX_FLAGS_RELEASE}"
+    "-ffunction-sections -fdata-sections ${CMAKE_CXX_FLAGS_RELEASE}"
 )
 if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
   set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} -s")
diff --git a/backends/arm/scripts/build_quantized_ops_aot_lib.sh b/backends/arm/scripts/build_quantized_ops_aot_lib.sh
index cd2fde710ae..d3d4b669f3b 100755
--- a/backends/arm/scripts/build_quantized_ops_aot_lib.sh
+++ b/backends/arm/scripts/build_quantized_ops_aot_lib.sh
@@ -20,9 +20,9 @@ echo "--------------------------------------------------------------------------
 
 # Since we only want to build the quantized_aot lib in the specified folder,
 # we want exactly the configuration set below and deleting the cache is OK.
-rm -f cmake-out-aot-lib/CMakeCache.txt 
+rm -f cmake-out-aot-lib/CMakeCache.txt
 
-cmake \
+CXXFLAGS="-fno-exceptions -fno-rtti" cmake \
     -DCMAKE_PREFIX_PATH="$CMAKE_PREFIX_PATH"    \
     -DCMAKE_BUILD_TYPE=${build_type}            \
     -DEXECUTORCH_BUILD_KERNELS_QUANTIZED=ON      \
diff --git a/backends/cadence/build_cadence_fusionG3.sh b/backends/cadence/build_cadence_fusionG3.sh
index 3e73dd6dc52..b0e1e777065 100644
--- a/backends/cadence/build_cadence_fusionG3.sh
+++ b/backends/cadence/build_cadence_fusionG3.sh
@@ -21,7 +21,7 @@ STEPWISE_BUILD=false
 
 if $STEPWISE_BUILD; then
     echo "Building ExecuTorch"
-    cmake -DCMAKE_INSTALL_PREFIX=cmake-out \
+    CXXFLAGS="-fno-exceptions -fno-rtti" cmake -DCMAKE_INSTALL_PREFIX=cmake-out \
         -DCMAKE_TOOLCHAIN_FILE=./backends/cadence/cadence.cmake  \
         -DCMAKE_BUILD_TYPE=Release \
         -DEXECUTORCH_ENABLE_EVENT_TRACER=OFF \
@@ -37,7 +37,7 @@ if $STEPWISE_BUILD; then
         -Bcmake-out .
 
     echo "Building any Cadence-specific binaries on top"
-    cmake -DBUCK2="$BUCK" \
+    CXXFLAGS="-fno-exceptions -fno-rtti" cmake -DBUCK2="$BUCK" \
         -DCMAKE_TOOLCHAIN_FILE=/home/zonglinpeng/ws/zonglinpeng/executorch/backends/cadence/cadence.cmake \
         -DCMAKE_INSTALL_PREFIX=cmake-out \
         -DCMAKE_BUILD_TYPE=Release \
@@ -61,7 +61,7 @@ if $STEPWISE_BUILD; then
 else
     echo "Building Cadence toolchain with ExecuTorch packages"
     cmake_prefix_path="${PWD}/cmake-out/lib/cmake/ExecuTorch;${PWD}/cmake-out/third-party/gflags"
-    cmake -DBUCK2="$BUCK" \
+    CXXFLAGS="-fno-exceptions -fno-rtti" cmake -DBUCK2="$BUCK" \
         -DCMAKE_PREFIX_PATH="${cmake_prefix_path}" \
         -DHAVE_SYS_STAT_H=ON \
         -DCMAKE_TOOLCHAIN_FILE=./backends/cadence/cadence.cmake \
diff --git a/backends/cadence/build_cadence_hifi4.sh b/backends/cadence/build_cadence_hifi4.sh
index e4821e1ff03..50fd5f032ab 100644
--- a/backends/cadence/build_cadence_hifi4.sh
+++ b/backends/cadence/build_cadence_hifi4.sh
@@ -21,7 +21,7 @@ STEPWISE_BUILD=false
 
 if $STEPWISE_BUILD; then
     echo "Building ExecuTorch"
-    cmake -DCMAKE_INSTALL_PREFIX=cmake-out \
+    CXXFLAGS="-fno-exceptions -fno-rtti" cmake -DCMAKE_INSTALL_PREFIX=cmake-out \
         -DCMAKE_TOOLCHAIN_FILE=./backends/cadence/cadence.cmake  \
         -DCMAKE_BUILD_TYPE=Release \
         -DEXECUTORCH_ENABLE_EVENT_TRACER=OFF \
@@ -36,7 +36,7 @@ if $STEPWISE_BUILD; then
         -Bcmake-out .
 
     echo "Building any Cadence-specific binaries on top"
-    cmake -DBUCK2="$BUCK" \
+    CXXFLAGS="-fno-exceptions -fno-rtti" cmake -DBUCK2="$BUCK" \
         -DCMAKE_TOOLCHAIN_FILE=./backends/cadence/cadence.cmake \
         -DCMAKE_INSTALL_PREFIX=cmake-out \
         -DCMAKE_BUILD_TYPE=Release \
@@ -60,7 +60,7 @@ if $STEPWISE_BUILD; then
 else
     echo "Building Cadence toolchain with ExecuTorch packages"
     cmake_prefix_path="${PWD}/cmake-out/lib/cmake/ExecuTorch;${PWD}/cmake-out/third-party/gflags"
-    cmake -DBUCK2="$BUCK" \
+    CXXFLAGS="-fno-exceptions -fno-rtti" cmake -DBUCK2="$BUCK" \
         -DCMAKE_PREFIX_PATH="${cmake_prefix_path}" \
         -DCMAKE_TOOLCHAIN_FILE=./backends/cadence/cadence.cmake \
         -DCMAKE_INSTALL_PREFIX=cmake-out \
diff --git a/backends/cadence/build_cadence_runner.sh b/backends/cadence/build_cadence_runner.sh
index 88687c5f756..a8f44719dc7 100755
--- a/backends/cadence/build_cadence_runner.sh
+++ b/backends/cadence/build_cadence_runner.sh
@@ -21,7 +21,7 @@ main() {
   cd "${EXECUTORCH_ROOT}"
 
   rm -rf cmake-out
-  cmake -DCMAKE_INSTALL_PREFIX=cmake-out \
+  CXXFLAGS="-fno-exceptions -fno-rtti" cmake -DCMAKE_INSTALL_PREFIX=cmake-out \
     -DCMAKE_BUILD_TYPE=Release \
     -DEXECUTORCH_BUILD_DEVTOOLS=ON \
     -DEXECUTORCH_ENABLE_EVENT_TRACER=ON \
@@ -33,7 +33,7 @@ main() {
   local build_dir="cmake-out/${example_dir}"
   local cmake_prefix_path="${PWD}/cmake-out/lib/cmake/ExecuTorch;${PWD}/cmake-out/third-party/gflags"
   rm -rf ${build_dir}
-  cmake -DCMAKE_PREFIX_PATH="${cmake_prefix_path}" \
+  CXXFLAGS="-fno-exceptions -fno-rtti" cmake -DCMAKE_PREFIX_PATH="${cmake_prefix_path}" \
     -DCMAKE_BUILD_TYPE=Release \
     -DEXECUTORCH_CADENCE_CPU_RUNNER=ON \
     -DEXECUTORCH_ENABLE_LOGGING=ON \
diff --git a/test/build_size_test.sh b/test/build_size_test.sh
index d970a023b5a..732880c60ac 100644
--- a/test/build_size_test.sh
+++ b/test/build_size_test.sh
@@ -15,7 +15,7 @@ cmake_install_executorch_lib() {
   echo "Installing libexecutorch.a"
   clean_executorch_install_folders
 
-  retry cmake -DBUCK2="$BUCK2" \
+  CXXFLAGS="-fno-exceptions -fno-rtti" retry cmake -DBUCK2="$BUCK2" \
           -DCMAKE_CXX_STANDARD_REQUIRED=ON \
           -DCMAKE_INSTALL_PREFIX=cmake-out \
           -DCMAKE_BUILD_TYPE=Release \
@@ -27,7 +27,7 @@ cmake_install_executorch_lib() {
 }
 
 test_cmake_size_test() {
-    retry cmake -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=cmake-out -Bcmake-out/test test
+    CXXFLAGS="-fno-exceptions -fno-rtti" retry cmake -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=cmake-out -Bcmake-out/test test
 
     echo "Build size test"
     cmake --build cmake-out/test -j9 --config Release
@@ -39,10 +39,6 @@ test_cmake_size_test() {
     ls -al cmake-out/test/size_test_all_ops
 }
 
-if [[ -z $BUCK2 ]]; then
-  BUCK2=buck2
-fi
-
 if [[ -z $PYTHON_EXECUTABLE ]]; then
   PYTHON_EXECUTABLE=python3
 fi