Fixing conditional CUDA compilation

src/CMakeLists.txt

@@ -7,7 +7,9 @@ add_executable(numerics main.cpp Matrix/SparseMatrix_unit_tests.cpp interpolatio
 
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-target_compile_options(numerics PUBLIC $<$<COMPILE_LANGUAGE:CUDA>:-Xcudafe "--display_error_number --diag_suppress=2885 --diag_suppress=2887  --diag_suppress=2888 --diag_suppress=186 --diag_suppress=111" --expt-extended-lambda>)
+if(CUDA_FOUND)
+	target_compile_options(numerics PUBLIC $<$<COMPILE_LANGUAGE:CUDA>:-Xcudafe "--display_error_number --diag_suppress=2885 --diag_suppress=2887  --diag_suppress=2888 --diag_suppress=186 --diag_suppress=111" --expt-extended-lambda>)
+endif()
 
 target_include_directories (numerics PUBLIC ${CUDA_INCLUDE_DIRS})
 target_include_directories (numerics PUBLIC ${CMAKE_CURRENT_SOURCE_DIR})