CI: avoid native march in tests

Author: nindanaoto

.github/workflows/test.yml

@@ -22,7 +22,7 @@ jobs:
         submodules: recursive
     - name: build
       run: |
-        cmake . -B build -G Ninja -DCMAKE_BUILD_TYPE=Release -DENABLE_TEST=ON
+        cmake . -B build -G Ninja -DCMAKE_BUILD_TYPE=Release -DENABLE_TEST=ON -DUSE_MARCH_NATIVE=OFF
         cd build
         ninja
     - name: test
@@ -46,7 +46,7 @@ jobs:
         submodules: recursive
     - name: build
       run: |
-        cmake . -B build -G Ninja -DCMAKE_BUILD_TYPE=Release -DENABLE_TEST=ON
+        cmake . -B build -G Ninja -DCMAKE_BUILD_TYPE=Release -DENABLE_TEST=ON -DUSE_MARCH_NATIVE=OFF
         cd build
         ninja
     - name: test
@@ -70,7 +70,7 @@ jobs:
         submodules: recursive
     - name: build
       run: |
-        cmake . -B build -G Ninja -DCMAKE_BUILD_TYPE=Release -DENABLE_TEST=ON -DUSE_CONCRETE=ON
+        cmake . -B build -G Ninja -DCMAKE_BUILD_TYPE=Release -DENABLE_TEST=ON -DUSE_CONCRETE=ON -DUSE_MARCH_NATIVE=OFF
         cd build
         ninja
     - name: test
@@ -94,7 +94,7 @@ jobs:
         submodules: recursive
     - name: build
       run: |
-        cmake . -B build -G Ninja -DCMAKE_BUILD_TYPE=Release -DENABLE_TUTORIAL=ON
+        cmake . -B build -G Ninja -DCMAKE_BUILD_TYPE=Release -DENABLE_TUTORIAL=ON -DUSE_MARCH_NATIVE=OFF
         cd build
         ninja
     - name: run tutorial
@@ -124,7 +124,7 @@ jobs:
         submodules: recursive
     - name: build
       run: |
-        /cmake-binary/bin/cmake . -B build -G Ninja -DCMAKE_BUILD_TYPE=Release -DCMAKE_CXX_COMPILER=clang++ -DCMAKE_C_COMPILER=clang -DCMAKE_LINKER_TYPE=LLD -DENABLE_TEST=ON
+        /cmake-binary/bin/cmake . -B build -G Ninja -DCMAKE_BUILD_TYPE=Release -DCMAKE_CXX_COMPILER=clang++ -DCMAKE_C_COMPILER=clang -DCMAKE_LINKER_TYPE=LLD -DENABLE_TEST=ON -DUSE_MARCH_NATIVE=OFF
         cd build
         ninja
     - name: test

CMakeLists.txt

@@ -2,13 +2,15 @@ cmake_minimum_required(VERSION 3.16)
 project(tfhe++ CXX C)
 set(CMAKE_CXX_STANDARD 20)
 option(DEBUG "Debug mode" OFF)
+option(USE_MARCH_NATIVE "Enable -march=native" ON)
+set(TFHEPP_BASE_CXX_FLAGS "-g -Wall -Wextra -pedantic -Wno-sign-compare")
+if(USE_MARCH_NATIVE)
+  string(APPEND TFHEPP_BASE_CXX_FLAGS " -march=native")
+endif()
 if(DEBUG)
-  set(CMAKE_CXX_FLAGS
-      "-march=native -g -Wall -Wextra -pedantic -Wno-sign-compare")
+  set(CMAKE_CXX_FLAGS "${TFHEPP_BASE_CXX_FLAGS}")
 else()
-  set(CMAKE_CXX_FLAGS
-      "-march=native -O3 -g -funroll-loops -Wall -Wextra -pedantic -Wno-sign-compare"
-  )
+  set(CMAKE_CXX_FLAGS "${TFHEPP_BASE_CXX_FLAGS} -O3 -funroll-loops")
   set(CMAKE_INTERPROCEDURAL_OPTIMIZATION TRUE)
 endif()
 

docs/Build.md

@@ -44,6 +44,11 @@ Build products:
 - `-DENABLE_SHARED=ON` — build `tfhe++` as a shared library.
 - `-DDEBUG=ON` — disable `-O3`, enable debug flags.
 
+Toolchain / CPU flags:
+
+- `-DUSE_MARCH_NATIVE=ON` (default) — enable `-march=native` for CPU‑tuned builds.
+- `-DUSE_MARCH_NATIVE=OFF` — build portable binaries (useful in CI or mixed CPUs).
+
 Randomness:
 
 - `-DUSE_BLAKE3=ON` (default) — BLAKE3‑XOF CSPRNG.
@@ -81,4 +86,3 @@ target_include_directories(my_target PRIVATE /path/to/prefix/include)
   AArch64 backend.
 - OpenMP is enabled when available; it accelerates batch encryption/decryption
   and some bootstrapping routines.
-