Added optional usage of OpenMP

CMakeLists.txt

@@ -6,6 +6,9 @@ project(Diffusion CXX)
 set(CMAKE_CXX_STANDARD 14)
 
 find_package(Eigen3 REQUIRED NO_MODULE)
+find_package(OpenMP)
+
+option(USE_OPENMP "Compile with OpenMP support" ON)
 
 add_subdirectory(app)
 add_subdirectory(src)

src/BTCSDiffusion.cpp

@@ -14,11 +14,16 @@
 #include <cstddef>
 #include <iomanip>
 #include <iterator>
-#include <omp.h>
 #include <ostream>
 #include <tuple>
 #include <vector>
 
+#ifdef _OPENMP
+#include <omp.h>
+#else
+#define omp_get_thread_num() 0
+#endif
+
 #include <iostream>
 
 constexpr int BTCS_MAX_DEP_PER_CELL = 3;

src/CMakeLists.txt

@@ -1,5 +1,11 @@
 find_package(OpenMP)
 
 add_library(diffusion OBJECT BTCSDiffusion.cpp BTCSDiffusion.hpp)
-target_link_libraries(diffusion Eigen3::Eigen OpenMP::OpenMP_CXX)
+
+target_link_libraries(diffusion Eigen3::Eigen)
+
+if(USE_OPENMP AND OpenMP_CXX_FOUND)
+  target_link_libraries(diffusion OpenMP::OpenMP_CXX)
+endif()
+
 target_include_directories(diffusion PUBLIC ${CMAKE_CURRENT_SOURCE_DIR})