feat(cmake): add Intel oneAPI compiler (ICX/ICPX) support

- Add IntelLLVM to all compiler detection points: CompilerWarnings,
  StandardProjectSettings, Hardening, Sanitizers, Tests,
  StaticAnalyzers, ProjectOptions
- Add Intel to CI matrix (Linux only)
- Install oneAPI directly from Intel apt repo
- Pre-install Conan deps with clang profile (binary compatible)
  and skip auto-provider via myproject_SKIP_CONAN_PROVIDER
- Skip gcovr and codecov for Intel (incompatible coverage format)

Signed-off-by: Helder Ferreira <helder@versatushpc.com.br>
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: viniciusferrao

.github/workflows/ci.yml

@@ -38,6 +38,7 @@ jobs:
           # you can specify the version after `-` like "llvm-15.0.2".
           - llvm-19.1.1
           - gcc-14
+          - intel
         generator:
           - "Ninja Multi-Config"
         build_type:
@@ -54,6 +55,12 @@ jobs:
           - os: windows-latest
             compiler: gcc-14
 
+          # Intel oneAPI is only available on Linux
+          - os: windows-latest
+            compiler: intel
+          - os: macos-latest
+            compiler: intel
+
         include:
           # Add appropriate variables for gcov version required. This will intentionally break
           # if you try to use a compiler that does not have gcov set
@@ -65,6 +72,10 @@ jobs:
             enable_ipo: Off
             gcov_executable: "llvm-cov gcov"
 
+          - compiler: intel
+            enable_ipo: Off
+            gcov_executable: gcov
+
           - os: macos-latest
             enable_ipo: Off
 
@@ -144,6 +155,7 @@ jobs:
 
 
       - name: Setup Cpp
+        if: ${{ matrix.compiler != 'intel' }}
         uses: aminya/setup-cpp@v1
         with:
           compiler: ${{ matrix.compiler }}
@@ -161,9 +173,39 @@ jobs:
           gcovr: true
           opencppcoverage: true
 
+      - name: Install Intel oneAPI
+        if: ${{ matrix.compiler == 'intel' }}
+        run: |
+          wget -qO- https://apt.repos.intel.com/intel-gpg-keys/GPG-PUB-KEY-INTEL-SW-PRODUCTS.PUB | sudo gpg --dearmor -o /usr/share/keyrings/oneapi-archive-keyring.gpg
+          echo "deb [signed-by=/usr/share/keyrings/oneapi-archive-keyring.gpg] https://apt.repos.intel.com/oneapi all main" | sudo tee /etc/apt/sources.list.d/oneAPI.list
+          sudo apt-get update
+          sudo apt-get install -y intel-oneapi-compiler-dpcpp-cpp cmake ninja-build ccache cppcheck gcovr
+
+      - name: Configure Intel oneAPI environment
+        if: ${{ matrix.compiler == 'intel' }}
+        run: |
+          echo "/opt/intel/oneapi/compiler/latest/bin" >> $GITHUB_PATH
+          echo "LD_LIBRARY_PATH=/opt/intel/oneapi/compiler/latest/lib:$LD_LIBRARY_PATH" >> $GITHUB_ENV
+          echo "CC=icx" >> $GITHUB_ENV
+          echo "CXX=icpx" >> $GITHUB_ENV
+
       - name: Install Conan and Lizard
         run: pip install conan lizard
 
+      - name: Configure Conan for Intel ICX
+        if: ${{ matrix.compiler == 'intel' }}
+        run: |
+          ICX=/opt/intel/oneapi/compiler/latest/bin/icx
+          ICX_CLANG_VER=$($ICX -dM -E -x c /dev/null 2>/dev/null | grep __clang_major__ | awk '{print $3}')
+          echo "ICX underlying Clang version: $ICX_CLANG_VER"
+          CC=clang CXX=clang++ conan profile detect --force
+          sed -i "s/compiler.version=.*/compiler.version=$ICX_CLANG_VER/" ~/.conan2/profiles/default
+          sed -i "s/compiler.cppstd=.*/compiler.cppstd=23/" ~/.conan2/profiles/default
+          cat ~/.conan2/profiles/default
+          conan install . --output-folder=build --build=missing -s build_type=Debug
+          conan install . --output-folder=build --build=missing -s build_type=Release
+          conan install . --output-folder=build --build=missing -s build_type=RelWithDebInfo
+
       - name: Pre-install Conan deps for macOS GCC
         if: ${{ runner.os == 'macOS' && contains(matrix.compiler, 'gcc') }}
         run: |
@@ -194,8 +236,12 @@ jobs:
         run: |
           EXTRA_CMAKE_ARGS=""
           # macOS GCC: deps pre-installed with libstdc++11 profile
+          if [[ "${{ matrix.compiler }}" == "intel" ]]; then
+            EXTRA_CMAKE_ARGS="-D${{ env.PROJECT_NAME }}_SKIP_CONAN_PROVIDER=ON -DCMAKE_PREFIX_PATH=$PWD/build"
+          fi
+          # macOS GCC: deps pre-installed with libstdc++11 profile
           if [[ "${{ runner.os }}" == "macOS" && "${{ matrix.compiler }}" =~ gcc ]]; then
-            EXTRA_CMAKE_ARGS="-Dmyproject_SKIP_CONAN_PROVIDER=ON -DCMAKE_PREFIX_PATH=$PWD/build"
+            EXTRA_CMAKE_ARGS="-D${{ env.PROJECT_NAME }}_SKIP_CONAN_PROVIDER=ON -DCMAKE_PREFIX_PATH=$PWD/build"
           fi
           cmake -S . -B ./build -G "${{matrix.generator}}" $EXTRA_CMAKE_ARGS -D${{ env.PROJECT_NAME }}_ENABLE_IPO=${{matrix.enable_ipo }} -DCMAKE_BUILD_TYPE:STRING=${{matrix.build_type}} -D${{ env.PROJECT_NAME }}_PACKAGING_MAINTAINER_MODE:BOOL=${{matrix.packaging_maintainer_mode}} -D${{ env.PROJECT_NAME }}_ENABLE_COVERAGE:BOOL=${{ matrix.build_type == 'Debug' }} -D${{ env.PROJECT_NAME }}_ENABLE_BLOATY:BOOL=OFF -D${{ env.PROJECT_NAME }}_ENABLE_INCLUDE_WHAT_YOU_USE:BOOL=OFF -DGIT_SHA:STRING=${{ github.sha }}
 
@@ -211,7 +257,10 @@ jobs:
         # See https://cmake.org/cmake/help/latest/manual/ctest.1.html for more detail
         run: |
           ctest -C ${{matrix.build_type}}
-          gcovr -j ${{env.nproc}} --root ../ --print-summary --xml-pretty --xml coverage.xml . --gcov-executable '${{ matrix.gcov_executable }}'
+          # Intel ICX uses a different coverage format incompatible with gcov
+          if [[ "${{ matrix.compiler }}" != "intel" ]]; then
+            gcovr -j ${{env.nproc}} --root ../ --print-summary --xml-pretty --xml coverage.xml . --gcov-executable '${{ matrix.gcov_executable }}'
+          fi
 
       - name: Windows - Test and coverage
         if: runner.os == 'Windows'
@@ -234,6 +283,7 @@ jobs:
 
 
       - name: Publish to codecov
+        if: ${{ matrix.compiler != 'intel' }}
         uses: codecov/codecov-action@v5
         with:
           fail_ci_if_error: true

.github/workflows/codeql-analysis.yml

@@ -81,11 +81,12 @@ jobs:
         gcovr: false
         opencppcoverage: false
 
-      # make sure coverage is only enabled for Debug builds, since it sets -O0 to make sure coverage
-      # has meaningful results
+    - name: Install Conan and Lizard
+      run: pip install conan lizard
+
     - name: Configure CMake
       run: |
-        cmake -S . -B ./build -G "${{matrix.generator}}" -DCMAKE_BUILD_TYPE:STRING=${{matrix.build_type}} -D${{ env.PROJECT_NAME }}_PACKAGING_MAINTAINER_MODE:BOOL=${{matrix.packaging_maintainer_mode}} -D${{ env.PROJECT_NAME }}_ENABLE_COVERAGE:BOOL=${{ matrix.build_type == 'Debug' }}
+        cmake -S . -B ./build -G "${{matrix.generator}}" -DCMAKE_BUILD_TYPE:STRING=${{matrix.build_type}} -D${{ env.PROJECT_NAME }}_PACKAGING_MAINTAINER_MODE:BOOL=${{matrix.packaging_maintainer_mode}} -D${{ env.PROJECT_NAME }}_ENABLE_COVERAGE:BOOL=${{ matrix.build_type == 'Debug' }} -D${{ env.PROJECT_NAME }}_ENABLE_BLOATY:BOOL=OFF -D${{ env.PROJECT_NAME }}_ENABLE_INCLUDE_WHAT_YOU_USE:BOOL=OFF
 
     # Initializes the CodeQL tools for scanning.
     - name: Initialize CodeQL

.github/workflows/wasm.yml

@@ -15,7 +15,7 @@ jobs:
   build-and-deploy:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Setup Emscripten
         uses: mymindstorm/setup-emsdk@v14
@@ -28,12 +28,32 @@ jobs:
           sudo apt-get install -y ninja-build
           pip install conan lizard
 
+      - name: Project Name
+        uses: cardinalby/export-env-action@v2
+        with:
+          envFile: '.github/constants.env'
+
+      - name: Configure Conan for Emscripten threading
+        run: |
+          # The cmake-conan provider auto-detects Emscripten but builds
+          # packages without threading flags. FTXUI requires pthreads.
+          # Configure the default Conan profile to pass -pthread so all
+          # packages (especially spdlog) are built with atomics support.
+          conan profile detect --force
+          echo "" >> ~/.conan2/profiles/default
+          echo "[conf]" >> ~/.conan2/profiles/default
+          echo "tools.build:cflags=[\"-pthread\"]" >> ~/.conan2/profiles/default
+          echo "tools.build:cxxflags=[\"-pthread\"]" >> ~/.conan2/profiles/default
+          echo "tools.build:sharedlinkflags=[\"-pthread\"]" >> ~/.conan2/profiles/default
+          echo "tools.build:exelinkflags=[\"-pthread\"]" >> ~/.conan2/profiles/default
+          cat ~/.conan2/profiles/default
+
       - name: Configure CMake
         run: |
           emcmake cmake -B build -G Ninja -DCMAKE_BUILD_TYPE=Release \
-            -Dmyproject_ENABLE_BLOATY=OFF \
-            -Dmyproject_ENABLE_INCLUDE_WHAT_YOU_USE=OFF \
-            -Dmyproject_ENABLE_CLANG_TIDY=OFF
+            -D${{ env.PROJECT_NAME }}_ENABLE_BLOATY=OFF \
+            -D${{ env.PROJECT_NAME }}_ENABLE_INCLUDE_WHAT_YOU_USE=OFF \
+            -D${{ env.PROJECT_NAME }}_ENABLE_CLANG_TIDY=OFF
 
       - name: Build all WASM targets
         run: emmake cmake --build build --target web-dist

CI_KNOWN_ISSUES.md

@@ -1,51 +1,27 @@
 # CI Known Issues
 
-This document tracks CI limitations and their resolutions. Most issues
-stemmed from the migration from CPM/FetchContent to Conan 2.0.
-
-## clang-tidy and Conan include paths (RESOLVED)
-
-**Status:** Fixed by removing the `-p` flag from `StaticAnalyzers.cmake`.
-
-**Root cause:** The `-p` flag in `CMAKE_CXX_CLANG_TIDY` options told CMake
-to have clang-tidy use `compile_commands.json` instead of passing the full
-compile command directly. This broke include resolution for Conan packages
-whose headers live in external `-isystem` paths (`~/.conan2/p/...`). Without
-`-p`, CMake appends `-- <full compile command>` to clang-tidy, which includes
-all `-isystem` paths and works reliably with Conan.
-
-## macOS + GCC Conan ABI (RESOLVED)
-
-**Status:** Fixed by overriding the Conan profile for macOS GCC in CI.
-
-**Root cause:** Conan's default macOS profile detects Apple Clang and sets
-`compiler.libcxx=libc++`. When building with GCC 14 (which uses `libstdc++`),
-this causes ABI mismatches at link time. Fixed by creating a GCC-specific
-Conan profile with `compiler=gcc` and `compiler.libcxx=libstdc++11`.
-
-## codecov fail_ci_if_error (RESOLVED)
-
-**Status:** Set to `true`. Requires `CODECOV_TOKEN` repository secret.
-
-**Setup:** Add `CODECOV_TOKEN` to the repository secrets at
-`Settings > Secrets and variables > Actions`. The token is obtained from
-[codecov.io](https://codecov.io) after linking the repository. Derived repos
-must configure their own token.
-
-## GCC coverage on macOS ARM
-
-**Status:** Skipped in `cmake/Tests.cmake` when `APPLE AND GNU`.
-
-**Root cause:** GCC's `--coverage` flag links against `libgcov`, which
-Apple's ARM linker can't find. Tests still run and pass; only coverage
-instrumentation is skipped. GCC coverage works on Linux.
-
-## Intel ICX coverage
-
-**Status:** gcovr skipped when `matrix.compiler == intel` in `ci.yml`.
-
-**Root cause:** Intel ICX produces coverage data in a format incompatible
-with `gcov`. Tests still run and pass; only the coverage report is skipped.
-
-**Possible fix:** Use `llvm-cov` from the oneAPI toolkit to process ICX
-coverage data. Nice-to-have, not a blocker.
+Tracked issues with links to GitHub issues for follow-up.
+
+## Resolved
+
+- **clang-tidy + Conan**: Fixed by removing `-p` flag from
+  `StaticAnalyzers.cmake`. clang-tidy works on all compilers.
+- **macOS GCC ABI mismatch**: Fixed by pre-installing Conan deps
+  with a GCC-specific `libstdc++11` profile.
+- **CodeQL missing Conan**: Fixed by adding `pip install conan lizard`
+  and disabling Bloaty/IWYU in the CodeQL workflow.
+- **codecov**: Set to `fail_ci_if_error: true`. Derived repos must
+  configure their own `CODECOV_TOKEN` repository secret from
+  [codecov.io](https://codecov.io).
+
+## Open
+
+- **WASM + Emscripten threading** ([#4](https://github.com/VersatusHPC/cmake_template/issues/4)):
+  spdlog built by Conan without atomics/bulk-memory, but the project
+  uses Emscripten pthreads. Emscripten pinned to 3.1.74 (Conan
+  doesn't support emcc 23+).
+- **macOS GCC coverage** ([#5](https://github.com/VersatusHPC/cmake_template/issues/5)):
+  Apple ARM linker can't find libgcov. Tests pass, coverage skipped.
+- **Intel ICX coverage** ([#6](https://github.com/VersatusHPC/cmake_template/issues/6)):
+  gcov incompatible with ICX coverage format. Tests pass, coverage
+  skipped.

ProjectOptions.cmake

@@ -12,7 +12,7 @@ macro(myproject_supports_sanitizers)
   if(EMSCRIPTEN)
     set(SUPPORTS_UBSAN OFF)
     set(SUPPORTS_ASAN OFF)
-  elseif((CMAKE_CXX_COMPILER_ID MATCHES ".*Clang.*" OR CMAKE_CXX_COMPILER_ID MATCHES ".*GNU.*") AND NOT WIN32)
+  elseif((CMAKE_CXX_COMPILER_ID MATCHES ".*Clang.*" OR CMAKE_CXX_COMPILER_ID MATCHES ".*GNU.*" OR CMAKE_CXX_COMPILER_ID STREQUAL "IntelLLVM") AND NOT WIN32)
 
     message(STATUS "Sanity checking UndefinedBehaviorSanitizer, it should be supported on this platform")
     set(TEST_PROGRAM "int main() { return 0; }")
@@ -33,7 +33,7 @@ macro(myproject_supports_sanitizers)
     set(SUPPORTS_UBSAN OFF)
   endif()
 
-  if((CMAKE_CXX_COMPILER_ID MATCHES ".*Clang.*" OR CMAKE_CXX_COMPILER_ID MATCHES ".*GNU.*") AND WIN32)
+  if((CMAKE_CXX_COMPILER_ID MATCHES ".*Clang.*" OR CMAKE_CXX_COMPILER_ID MATCHES ".*GNU.*" OR CMAKE_CXX_COMPILER_ID STREQUAL "IntelLLVM") AND WIN32)
     set(SUPPORTS_ASAN OFF)
   else()
     if (NOT WIN32)

cmake/CompilerWarnings.cmake

@@ -91,13 +91,12 @@ function(
 
   if(MSVC)
     set(PROJECT_WARNINGS_CXX ${MSVC_WARNINGS})
-  elseif(CMAKE_CXX_COMPILER_ID MATCHES ".*Clang")
+  elseif(CMAKE_CXX_COMPILER_ID MATCHES ".*Clang" OR CMAKE_CXX_COMPILER_ID STREQUAL "IntelLLVM")
     set(PROJECT_WARNINGS_CXX ${CLANG_WARNINGS})
   elseif(CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
     set(PROJECT_WARNINGS_CXX ${GCC_WARNINGS})
   else()
     message(AUTHOR_WARNING "No compiler warnings set for CXX compiler: '${CMAKE_CXX_COMPILER_ID}'")
-    # TODO support Intel compiler
   endif()
 
   # use the same warning flags for C

cmake/Emscripten.cmake

@@ -89,9 +89,9 @@ function(myproject_configure_wasm_target target)
       "-sUSE_PTHREADS=1"
       "-sPROXY_TO_PTHREAD=1"
       "-sPTHREAD_POOL_SIZE=${myproject_WASM_PTHREAD_POOL_SIZE}"
-      # Enable asyncify for emscripten_sleep and async operations
-      "-sASYNCIFY=1"
-      "-sASYNCIFY_STACK_SIZE=${myproject_WASM_ASYNCIFY_STACK_SIZE}"
+      # NOTE: Asyncify is disabled because it conflicts with pthreads +
+      # wasm-exceptions on Emscripten 3.1.x (wasm-opt UNREACHABLE crash).
+      # PROXY_TO_PTHREAD handles async operations instead.
       # Memory configuration
       "-sALLOW_MEMORY_GROWTH=1"
       "-sINITIAL_MEMORY=${myproject_WASM_INITIAL_MEMORY}"

cmake/Hardening.cmake

@@ -13,7 +13,7 @@ macro(
     message(STATUS "*** MSVC flags: /sdl /DYNAMICBASE /guard:cf /NXCOMPAT /CETCOMPAT")
     list(APPEND NEW_LINK_OPTIONS /NXCOMPAT /CETCOMPAT)
 
-  elseif(CMAKE_CXX_COMPILER_ID MATCHES ".*Clang|GNU")
+  elseif(CMAKE_CXX_COMPILER_ID MATCHES ".*Clang|GNU" OR CMAKE_CXX_COMPILER_ID STREQUAL "IntelLLVM")
     list(APPEND NEW_CXX_DEFINITIONS -D_GLIBCXX_ASSERTIONS)
     message(STATUS "*** GLIBC++ Assertions (vector[], string[], ...) enabled")
 

cmake/Sanitizers.cmake

@@ -7,7 +7,7 @@ function(
   ENABLE_SANITIZER_THREAD
   ENABLE_SANITIZER_MEMORY)
 
-  if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU" OR CMAKE_CXX_COMPILER_ID MATCHES ".*Clang")
+  if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU" OR CMAKE_CXX_COMPILER_ID MATCHES ".*Clang" OR CMAKE_CXX_COMPILER_ID STREQUAL "IntelLLVM")
     set(SANITIZERS "")
 
     if(${ENABLE_SANITIZER_ADDRESS})
@@ -30,7 +30,7 @@ function(
       endif()
     endif()
 
-    if(${ENABLE_SANITIZER_MEMORY} AND CMAKE_CXX_COMPILER_ID MATCHES ".*Clang")
+    if(${ENABLE_SANITIZER_MEMORY} AND (CMAKE_CXX_COMPILER_ID MATCHES ".*Clang" OR CMAKE_CXX_COMPILER_ID STREQUAL "IntelLLVM"))
       message(
         WARNING
           "Memory sanitizer requires all the code (including libc++) to be MSan-instrumented otherwise it reports false positives"

cmake/StandardProjectSettings.cmake

@@ -18,7 +18,7 @@ endif()
 set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 
 # Enhance error reporting and compiler messages
-if(CMAKE_CXX_COMPILER_ID MATCHES ".*Clang")
+if(CMAKE_CXX_COMPILER_ID MATCHES ".*Clang" OR CMAKE_CXX_COMPILER_ID STREQUAL "IntelLLVM")
     add_compile_options($<$<COMPILE_LANGUAGE:C>:-fcolor-diagnostics> $<$<COMPILE_LANGUAGE:CXX>:-fcolor-diagnostics>)
 elseif(CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
     add_compile_options($<$<COMPILE_LANGUAGE:C>:-fdiagnostics-color=always>