Fix emulated arch CI: avoid shell redirection of angle brackets

Pass the emulated register size as a plain integer CMake variable
(XSIMD_EMULATED_SIZE) instead of constructing emulated<N> in the
shell. CMakeLists.txt assembles the define via add_compile_definitions,
which handles escaping for the compiler invocation.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: AntoinePrv

.github/workflows/emulated.yml

@@ -27,8 +27,6 @@ jobs:
       if: ${{ matrix.sys.compiler == 'g++' }}
       run: |
         echo "CXXFLAGS=-Wno-noexcept-type -Wno-stringop-overflow -Wno-maybe-uninitialized" >> $GITHUB_ENV
-    - name: Set emulated arch
-      run: echo "XSIMD_ARCH=emulated<${{ matrix.sys.size }}>" >> $GITHUB_ENV
     - name: Configure build
       run: |
         cmake -B_build \
@@ -38,7 +36,8 @@ jobs:
           -DCMAKE_BUILD_TYPE=Release \
           -DCMAKE_CXX_COMPILER=${{ matrix.sys.compiler }} \
           -DXSIMD_ENABLE_WERROR=ON \
-          -DCMAKE_CXX_FLAGS="-DXSIMD_DEFAULT_ARCH=$XSIMD_ARCH -DXSIMD_WITH_EMULATED=1 $CXXFLAGS" \
+          -DXSIMD_EMULATED_SIZE=${{ matrix.sys.size }} \
+          -DCMAKE_CXX_FLAGS="$CXXFLAGS" \
           -GNinja
     - name: Build
       run: ninja -C _build

CMakeLists.txt

@@ -93,6 +93,12 @@ target_include_directories(xsimd INTERFACE
 OPTION(ENABLE_XTL_COMPLEX "enables support for xcomplex defined in xtl" OFF)
 OPTION(BUILD_TESTS "xsimd test suite" OFF)
 
+set(XSIMD_EMULATED_SIZE "" CACHE STRING "If set, compile with emulated<N> as the default arch (N = register size in bits)")
+if(XSIMD_EMULATED_SIZE)
+    add_compile_definitions("XSIMD_DEFAULT_ARCH=emulated<${XSIMD_EMULATED_SIZE}>")
+    add_compile_definitions(XSIMD_WITH_EMULATED=1)
+endif()
+
 if(ENABLE_XTL_COMPLEX)
     find_package(xtl 0.8.0 REQUIRED)
     target_compile_features(xsimd INTERFACE cxx_std_14)