diff --git a/examples/COUPLE/simple/CMakeLists.txt b/examples/COUPLE/simple/CMakeLists.txt
index f4cf680f61..4112eaa4e7 100644
--- a/examples/COUPLE/simple/CMakeLists.txt
+++ b/examples/COUPLE/simple/CMakeLists.txt
@@ -4,11 +4,14 @@ project(simple CXX)
 set(LAMMPS_SRC_DIRECTORY "" CACHE PATH "Path for lammps source")
 if(NOT LAMMPS_SRC_DIRECTORY STREQUAL "" AND EXISTS ${LAMMPS_SRC_DIRECTORY}/cmake/CMakeLists.txt)
   option(BUILD_LIB "Build LAMMPS library" ON)
-  option(LAMMPS_CREATE_IN_SOURCES_INCLUDE_DIR "include in-source lammps/ include dir" ON)
   add_subdirectory(${LAMMPS_SRC_DIRECTORY}/cmake lammps)
 else()
   find_package(LAMMPS REQUIRED)
 endif()
 
-add_executable(simple simple.cpp)
-target_link_libraries(simple LAMMPS::lammps)
+add_executable(simpleCC simple.cpp)
+target_link_libraries(simpleCC LAMMPS::lammps)
+
+enable_language(C)
+add_executable(simpleC simple.c)
+target_link_libraries(simpleC LAMMPS::lammps)