diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 51571447..60fa8374 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -321,9 +321,9 @@ if (BUILDSWIGNODE)
                                      "${CMAKE_CURRENT_SOURCE_DIR}/*.hpp"
                                      "${CMAKE_CURRENT_SOURCE_DIR}/*.hxx")
         foreach (srcfile ${srcfiles})
-          get_filename_component(csource ${srcfile} NAME_WE)
           file (COPY ${CMAKE_CURRENT_SOURCE_DIR}/${srcfile} DESTINATION ${CMAKE_CURRENT_BINARY_DIR}/jsupm_${libname})
           if(${srcfile} MATCHES ".c$")
+            get_filename_component(csource ${srcfile} NAME_WE)
             file (RENAME ${CMAKE_CURRENT_BINARY_DIR}/jsupm_${libname}/${srcfile} ${CMAKE_CURRENT_BINARY_DIR}/jsupm_${libname}/${csource}_c.c)
             set (upm_LIB_SRCS_GYP "'${csource}_c.c',\n${upm_LIB_SRCS_GYP}")
           elseif (${srcfile} MATCHES ".cxx$" OR ${srcfile} MATCHES ".cpp$")