Temporary header file '/tmp/rUox2AwmFJ/dump1.h' with the following content will be compiled to create GCC translation unit dump: // add defines #define __STDC_VERSION__ 201710L #define _GXX_NULLPTR_T #define CLUTTER_ENABLE_COMPOSITOR_API 1 #define _REGEX_NELTS(n) #define _Atomic #define PACKED // add includes #include "/usr/include/parmetis.h" The GCC parameters: gcc -fdump-lang-raw -fkeep-inline-functions -c -x c++ -fpermissive -w "/tmp/rUox2AwmFJ/dump1.h" In file included from /tmp/rUox2AwmFJ/dump1.h:11: /usr/include/parmetis.h:17:10: fatal error: mpi.h: No such file or directory 17 | #include | ^~~~~~~ compilation terminated.