Clang transpiler integration

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "deps/occa-transpiler"]
+	path = deps/occa-transpiler
+	url = https://github.com/libocca/occa-transpiler.git

CMakeLists.txt

@@ -37,6 +37,7 @@ option(OCCA_ENABLE_DPCPP "Build with SYCL/DPCPP if available" ON)
 option(OCCA_ENABLE_TESTS    "Build tests"               OFF)
 option(OCCA_ENABLE_EXAMPLES "Build simple examples"     OFF)
 option(OCCA_ENABLE_FORTRAN  "Enable Fortran interface"  OFF)
+option(OCCA_CLANG_BASED_TRANSPILER      "Build with occa-transpiler dependecy" OFF)
 
 if(OCCA_ENABLE_FORTRAN)
   enable_language(Fortran)
@@ -67,6 +68,20 @@ else()
   set(OCCA_OS "OCCA_WINDOWS_OS")
 endif()
 
+# INFO: order is important, deps should not apply compiler flags
+if (OCCA_CLANG_BASED_TRANSPILER)
+    include(cmake/CPM_0.38.6.cmake)
+    include(cmake/GitSubmodules.cmake)
+
+    init_submodules(${PROJECT_SOURCE_DIR})
+
+    CPMAddPackage(
+        NAME occa-transpiler
+        SOURCE_DIR ${CMAKE_SOURCE_DIR}/deps/occa-transpiler
+        OPTIONS "TRANSPILER_TESTS OFF"
+    )
+endif()
+
 include(SetCompilerFlags)
 include(CheckCXXCompilerFlag)
 
@@ -113,6 +128,14 @@ target_include_directories(libocca PRIVATE
   $<BUILD_INTERFACE:${OCCA_SOURCE_DIR}/src>)
 
 target_compile_definitions(libocca PRIVATE -DUSE_CMAKE)
+if (OCCA_CLANG_BASED_TRANSPILER)
+    target_link_libraries(libocca
+        PRIVATE
+            occa-transpiler
+    )
+    target_compile_definitions(libocca PRIVATE -DBUILD_WITH_CLANG_BASED_TRANSPILER)
+endif()
+
 #=======================================
 
 #---[ OpenMP ]--------------------------

README.md

@@ -48,6 +48,7 @@ Mission critical computational science and engineering applications from the pub
  - SYCL 2020 or later
  - OpenCL 2.0 or later
  - OpenMP 4.0 or later
+ - C++ support with clang based occa-transpiler
 
 ## Build, Test, Install
 
@@ -67,6 +68,14 @@ $ cmake --install build --prefix install
 
 If dependencies are installed in a non-standard location, set the corresponding [environment variable](INSTALL.md#dependency-paths) to this path. 
 
+For building with C++ support/occa-transpiler: 
+```shell
+$ mkdir build
+$ cd build
+$ cmake -DCMAKE_BUILD_TYPE=Release -DOCCA_CLANG_BASED_TRANSPILER=ON ..
+$ cmake --build . --parallel <number-of-threads> 
+$ cmake --install . --prefix install
+```
 
 ## Use