Temporary header file '/tmp/I_XNKnOaUj/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 #define getaddrinfo_a(a,b,c,d) // add includes #include "/usr/include/saclib/hfloats.h" #include "/usr/include/saclib/saclib.h" #include "/usr/include/saclib/sacmacros.h" #include "/usr/include/saclib/sacproto.h" #include "/usr/include/saclib/sacsys.h" #include "/usr/include/saclib/sactypes.h" #include "/usr/include/saclib/sysdep.h" // add classes ieee754_double* tmp_add_class_0; ieee754_float* tmp_add_class_1; ieee854_long_double* tmp_add_class_2; The GCC parameters: gcc -fdump-lang-raw -fkeep-inline-functions -c -x c++ -fpermissive -w "/tmp/I_XNKnOaUj/dump1.h" In file included from /usr/include/saclib/saclib.h:11, from /tmp/I_XNKnOaUj/dump1.h:13: /usr/include/saclib/hfloats.h:39:5: error: conflicting declaration ‘typedef struct ieee_rep ieee_rep’ 39 | } ieee_rep; | ^~~~~~~~ In file included from /tmp/I_XNKnOaUj/dump1.h:12: /usr/include/saclib/hfloats.h:39:5: note: previous declaration as ‘typedef struct ieee_rep ieee_rep’ 39 | } ieee_rep; | ^~~~~~~~ /usr/include/saclib/hfloats.h:55:6: error: conflicting declaration ‘typedef union ieee ieee’ 55 | } ieee; | ^~~~ /usr/include/saclib/hfloats.h:55:6: note: previous declaration as ‘typedef union ieee ieee’ 55 | } ieee; | ^~~~ /usr/include/saclib/hfloats.h:93:3: error: conflicting declaration ‘typedef struct interval interval’ 93 | } interval; | ^~~~~~~~ /usr/include/saclib/hfloats.h:93:3: note: previous declaration as ‘typedef struct interval interval’ 93 | } interval; | ^~~~~~~~